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  • need to align part of list item to right of li - using CSS3 Jquery column-layout

    - by Brad
    Using this jquery script to acheive CSS3 3-columns, to display a list of members alphabetically. I need it to display this way, which is does: A D B E C F Here is what I am using http://www.csscripting.com/css-multi-column/example6.php? (using this js file http://www.csscripting.com/js/v1.0beta/css3-multi-column.js) To the right of each member, it has their phone extension, which I want to float to the right, so it easy to read. I tried putting the phone extension within a div and span and when I do that, it tends to screw up at the last item in each column, by placing the person's name correctly, but their extension is the very first item in the next column. Screenshot: http://cl.ly/fq4 of what it is doing HTML Code: <div class="Article3Col"> <ul> <li>Doe, John <div style="float:right;"> 8317 </div> </li> <li>Doe, Sally <div style="float:right;"> 8729 </div> </li> <li>Doe, John <div style="float:right;"> 8317 </div> </li> <li>Doe, Sally <div style="float:right;"> 8729 </div> </li> <li>Doe, John <div style="float:right;"> 8317 </div> </li> <li>Doe, Sally <div style="float:right;"> 8729 </div> </li> <li>Doe, John <div style="float:right;"> 8317 </div> </li> <li>Doe, Sally <div style="float:right;"> 8729 </div> </li> <li>Doe, John <div style="float:right;"> 8317 </div> </li> <li>Doe, Sally <div style="float:right;"> 8729 </div> </li> <li>Doe, John <div style="float:right;"> 8317 </div> </li> <li>Doe, Sally <div style="float:right;"> 8729 </div> </li> <li>Doe, John <div style="float:right;"> 8317 </div> </li> <li>Doe, Sally <div style="float:right;"> 8729 </div> </li> <li>Doe, John <div style="float:right;"> 8317 </div> </li> <li>Doe, Sally <div style="float:right;"> 8729 </div> </li> <li>Doe, John <div style="float:right;"> 8317 </div> </li> <li>Doe, Sally <div style="float:right;"> 8729 </div> </li> </ul> </div> CSS: .Article3Col { column-count:3; } Any help is appreciated.

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  • Themes wont work when using Server Side Tags on an ASP.NET Page

    - by Sumit Sharma
    The code for the asp.net page is: <div class="facebox_content"> <% if (CurrentUser.Role == "Free") { %> <table cellpadding="0" cellspacing="0" style="border-collapse:collapse;width:380px;"> <tr> <td> User Name : </td> <td> Membership Cost : </td> </tr> <tr> <td style="width:190px;"> <asp:TextBox ID="txtUserName" Enabled="false" runat="server" Text="<%= CurrentUser.Name %>"/> </td> <td style="width:190px;"> <asp:TextBox ID="txtCost" Enabled="false" runat="server" Text="2000"/> </td> </tr> <tr> <td> <br /> Cheque / Draft No.: </td> <td> <br /> Bank Drawn On : </td> </tr> <tr> <td style="width:190px;"> <asp:TextBox ID="txtChqNo" runat="server"></asp:TextBox> </td> <td style="width:190px;"> <asp:TextBox ID="txtBankName" runat="server"></asp:TextBox> </td> </tr> <tr> <td> <br /> Date : </td> <td> <br /> City : </td> </tr> <tr> <td style="width:190px;"> <asp:TextBox ID="txtDate" runat="server"></asp:TextBox> </td> <td style="width:190px;"> <asp:TextBox ID="txtCity" runat="server"></asp:TextBox> </td> </tr> </table> <% } else if(CurrentUser.Role == "Pending") { %> <p style="text-align:justify;"> Your Request is pending with our Administrators. Please be patient while your request is processed. Usually it takes 2-4 Days for your request to be processed after the payment has been received. </p> <% } else if(CurrentUser.Role == "Paid") { %> <p style="text-align:justify;"> You are already a Paid Member of Website </p> <% } %> The code for the C# file is: protected void Page_PreInit(object sender, EventArgs e) { this.Theme = CurrentUser.Theme; } protected void Page_Load(object sender, EventArgs e) { txtUserName.Text = CurrentUser.Name; ConfirmButton.Attributes.Add("onclick", "javascript:document.getElementById('" + lblMsg.ClientID + "').style.display='none';"); if (CurrentUser.Role != "Free") ConfirmButton.Visible = false; } The code is giving the following error: The Controls collection cannot be modified because the control contains code blocks (i.e. <% ... %>). Description: An unhandled exception occurred during the execution of the current web request. Please review the stack trace for more information about the error and where it originated in the code. Exception Details: System.Web.HttpException: The Controls collection cannot be modified because the control contains code blocks (i.e. <% ... %>). Source Error: An unhandled exception was generated during the execution of the current web request. Information regarding the origin and location of the exception can be identified using the exception stack trace below. Stack Trace: [HttpException (0x80004005): The Controls collection cannot be modified because the control contains code blocks (i.e. <% ... %>).] System.Web.UI.ControlCollection.Add(Control child) +8678903 System.Web.UI.PageTheme.SetStyleSheet() +478 System.Web.UI.Page.OnInit(EventArgs e) +8699660 System.Web.UI.Control.InitRecursive(Control namingContainer) +333 System.Web.UI.Page.ProcessRequestMain(Boolean includeStagesBeforeAsyncPoint, Boolean includeStagesAfterAsyncPoint) +378 Please some one help me out..!!

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  • Html.BeginForm() not rendering properly

    - by Taskos George
    While searching in stackoverflow the other questions didn't exactly helped in my situation. How it would be possible to debug such an error like the one that the Html.BeginForm does not properly rendered to the page. I use this code @model ExtremeProduction.Models.SelectUserGroupsViewModel @{ ViewBag.Title = "User Groups"; } <h2>Groups for user @Html.DisplayFor(model => model.UserName)</h2> <hr /> @using (Html.BeginForm("UserGroups", "Account", FormMethod.Post, new { encType = "multipart/form-data", id = "userGroupsForm" })) { @Html.AntiForgeryToken() <div class="form-horizontal"> @Html.ValidationSummary(true) <div class="form-group"> <div class="col-md-10"> @Html.HiddenFor(model => model.UserName) </div> </div> <h4>Select Group Assignments</h4> <br /> <hr /> <table> <tr> <th> Select </th> <th> Group </th> </tr> @Html.EditorFor(model => model.Groups) </table> <br /> <hr /> <div class="form-group"> <div class="col-md-offset-2 col-md-10"> <input type="submit" value="Save" class="btn btn-default" /> </div> </div> </div> } <div> @Html.ActionLink("Back to List", "Index") </div> EDIT: Added the Model // Wrapper for SelectGroupEditorViewModel to select user group membership: public class SelectUserGroupsViewModel { public string UserName { get; set; } public string FirstName { get; set; } public string LastName { get; set; } public List<SelectGroupEditorViewModel> Groups { get; set; } public SelectUserGroupsViewModel() { this.Groups = new List<SelectGroupEditorViewModel>(); } public SelectUserGroupsViewModel(ApplicationUser user) : this() { this.UserName = user.UserName; this.FirstName = user.FirstName; this.LastName = user.LastName; var Db = new ApplicationDbContext(); // Add all available groups to the public list: var allGroups = Db.Groups; foreach (var role in allGroups) { // An EditorViewModel will be used by Editor Template: var rvm = new SelectGroupEditorViewModel(role); this.Groups.Add(rvm); } // Set the Selected property to true where user is already a member: foreach (var group in user.Groups) { var checkUserRole = this.Groups.Find(r => r.GroupName == group.Group.Name); checkUserRole.Selected = true; } } } // Used to display a single role group with a checkbox, within a list structure: public class SelectGroupEditorViewModel { public SelectGroupEditorViewModel() { } public SelectGroupEditorViewModel(Group group) { this.GroupName = group.Name; this.GroupId = group.Id; } public bool Selected { get; set; } [Required] public int GroupId { get; set; } public string GroupName { get; set; } } public class Group { public Group() { } public Group(string name) : this() { Roles = new List<ApplicationRoleGroup>(); Name = name; } [Key] [Required] public virtual int Id { get; set; } public virtual string Name { get; set; } public virtual ICollection<ApplicationRoleGroup> Roles { get; set; } } ** EDIT ** And I get this form http://i834.photobucket.com/albums/zz268/gtas/formmine_zpsf6470e02.png I should receive a form like the one that I copied the code like this http://i834.photobucket.com/albums/zz268/gtas/formcopied_zpsdb2f129e.png Any ideas where or how to look the source of evil that makes my life hard for some time now?

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  • Anyone succeeded at injecting Interfaces into Entity Framework 4 Entities, using T4?

    - by Ciel
    Hello: POCO sort of leaves me wanting: (how can I say I use DI/IoC, if the Repository is not the only place that is creating the entities?)...hence my desire to lock it down, get rid of the temptation of newing up POCOs or EntityObjects anywhere in the code, and just allowing entity interfaces above the Repository/Factory layer. For a second there, I nearly thought I had it...was editing EF4's T4 in order to inject in an Interface def. Was going swimmingly, compiled and worked, until I got to the Associations... I wrapped them with a ICollection, and renamed the underlying original collection with a prefix of Wrapped. Unfortunately, when run, throws an error: //The Member 'WrappedSubExamples' in the CLR type 'XAct.App.Data.Model.EF4.Example' is not present in the conceptual model type 'XAct.App.Data.Model.Entity.Example'. var examples = context2.CreateObjectSet(); My T4 segment I used was (this may not work, as it's the longest code snippet I've ever posted here...sorry): #region Generic Property Abstraction <# if (navProperty.ToEndMember.RelationshipMultiplicity == RelationshipMultiplicity.Many) {#> //XAct.App Generic Wrapper: <#=code.SpaceAfter(NewModifier(navProperty))#><#=Accessibility.ForProperty(navProperty)#> ICollection<I<#=MultiSchemaEscape(navProperty.ToEndMember.GetEntityType(), code)#>> <#=code.Escape(navProperty)#> { get { if (_X<#=code.Escape(navProperty)# == null){ _X<#=code.Escape(navProperty)# = new WrappedCollection,<#=MultiSchemaEscape(navProperty.ToEndMember.GetEntityType(), code)#(this.<#=(navProperty.ToEndMember.RelationshipMultiplicity == RelationshipMultiplicity.Many)?"Wrapped":""#<#=code.Escape(navProperty)#); } return _X<#=code.Escape(navProperty)#; } } private ICollection _X<#=code.Escape(navProperty)#; <# } else { # <#=code.SpaceAfter(NewModifier(navProperty))#<#=Accessibility.ForProperty(navProperty)# I<#=MultiSchemaEscape(navProperty.ToEndMember.GetEntityType(), code)# <#=code.Escape(navProperty)# { get { return (I<#=code.Escape(navProperty)#)this.Wrapped<#=code.Escape(navProperty)#; } set { this.Wrapped<#=code.Escape(navProperty)# = value as <#=code.Escape(navProperty)#; } } <# } # #endregion which then wraps the original collection, renamed with the prefix 'Wrapped': /// <summary> /// <#=SummaryComment(navProperty)#> /// </summary><#=LongDescriptionCommentElement(navProperty, region.CurrentIndentLevel) #> [XmlIgnoreAttribute()] [SoapIgnoreAttribute()] [DataMemberAttribute()] [EdmRelationshipNavigationPropertyAttribute("<#=navProperty.RelationshipType.NamespaceName#>", "<#=navProperty.RelationshipType.Name#>", "<#=navProperty.ToEndMember.Name#>")] <# if (navProperty.ToEndMember.RelationshipMultiplicity == RelationshipMultiplicity.Many) { #> <#=code.SpaceAfter(NewModifier(navProperty))#><#=Accessibility.ForProperty(navProperty)#> EntityCollection<<#=MultiSchemaEscape(navProperty.ToEndMember.GetEntityType(), code)#>> Wrapped<#=code.Escape(navProperty)#> { <#=code.SpaceAfter(Accessibility.ForGetter(navProperty))#>get { return ((IEntityWithRelationships)this).RelationshipManager.GetRelatedCollection<<#=MultiSchemaEscape(navProperty.ToEndMember.GetEntityType(), code)#>>("<#=navProperty.RelationshipType.FullName#>", "<#=navProperty.ToEndMember.Name#>"); } <#=code.SpaceAfter(Accessibility.ForSetter(navProperty))#>set { if ((value != null)) { ((IEntityWithRelationships)this).RelationshipManager.InitializeRelatedCollection<<#=MultiSchemaEscape(navProperty.ToEndMember.GetEntityType(), code)#>>("<#=navProperty.RelationshipType.FullName#>", "<#=navProperty.ToEndMember.Name#>", value); } } } <# } else { #> <#=code.SpaceAfter(NewModifier(navProperty))#><#=Accessibility.ForProperty(navProperty)#> <#=MultiSchemaEscape(navProperty.ToEndMember.GetEntityType(), code)#> Wrapped<#=code.Escape(navProperty)#> { <#=code.SpaceAfter(Accessibility.ForGetter(navProperty))#>get { return ((IEntityWithRelationships)this).RelationshipManager.GetRelatedReference<<#=MultiSchemaEscape(navProperty.ToEndMember.GetEntityType(), code)#>>("<#=navProperty.RelationshipType.FullName#>", "<#=navProperty.ToEndMember.Name#>").Value; } <#=code.SpaceAfter(Accessibility.ForSetter(navProperty))#>set { ((IEntityWithRelationships)this).RelationshipManager.GetRelatedReference<<#=MultiSchemaEscape(navProperty.ToEndMember.GetEntityType(), code)#>>("<#=navProperty.RelationshipType.FullName#>", "<#=navProperty.ToEndMember.Name#>").Value = value; } } <# string refPropertyName = navProperty.Name + "Reference"; if (entity.Members.Any(m => m.Name == refPropertyName)) { // 6017 is the same error number that EntityClassGenerator uses. Errors.Add(new System.CodeDom.Compiler.CompilerError(SourceCsdlPath, -1, -1, "6017", String.Format(CultureInfo.CurrentCulture, GetResourceString("Template_ConflictingGeneratedNavPropName"), navProperty.Name, entity.FullName, refPropertyName))); } #> /// <summary> /// <#=SummaryComment(navProperty)#> /// </summary><#=LongDescriptionCommentElement(navProperty, region.CurrentIndentLevel)#> [BrowsableAttribute(false)] [DataMemberAttribute()] <#=Accessibility.ForProperty(navProperty)#> EntityReference<<#=MultiSchemaEscape(navProperty.ToEndMember.GetEntityType(), code)#>> <#=refPropertyName#> { <#=code.SpaceAfter(Accessibility.ForGetter(navProperty))#>get { return ((IEntityWithRelationships)this).RelationshipManager.GetRelatedReference<<#=MultiSchemaEscape(navProperty.ToEndMember.GetEntityType(), code)#>>("<#=navProperty.RelationshipType.FullName#>", "<#=navProperty.ToEndMember.Name#>"); } <#=code.SpaceAfter(Accessibility.ForSetter(navProperty))#>set { if ((value != null)) { ((IEntityWithRelationships)this).RelationshipManager.InitializeRelatedReference<<#=MultiSchemaEscape(navProperty.ToEndMember.GetEntityType(), code)#>>("<#=navProperty.RelationshipType.FullName#>", "<#=navProperty.ToEndMember.Name#>", value); } } } <# } The point is...it bugs out. I've tried various solutions...none worked. Any ideas -- or is this just a wild goose chase, and time to give it up?

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  • Pointers to Derived Class Objects Losing vfptr

    - by duckworthd
    To begin, I am trying to write a run-of-the-mill, simple Ray Tracer. In my Ray Tracer, I have multiple types of geometries in the world, all derived from a base class called "SceneObject". I've included the header for it here. /** Interface for all objects that will appear in a scene */ class SceneObject { public: mat4 M, M_inv; Color c; SceneObject(); ~SceneObject(); /** The transformation matrix to be applied to all points of this object. Identity leaves the object in world frame. */ void setMatrix(mat4 M); void setMatrix(MatrixStack mStack); void getMatrix(mat4& M); /** The color of the object */ void setColor(Color c); void getColor(Color& c); /** Alter one portion of the color, leaving the rest as they were. */ void setDiffuse(vec3 rgb); void setSpecular(vec3 rgb); void setEmission(vec3 rgb); void setAmbient(vec3 rgb); void setShininess(double s); /** Fills 'inter' with information regarding an intersection between this object and 'ray'. Ray should be in world frame. */ virtual void intersect(Intersection& inter, Ray ray) = 0; /** Returns a copy of this SceneObject */ virtual SceneObject* clone() = 0; /** Print information regarding this SceneObject for debugging */ virtual void print() = 0; }; As you can see, I've included a couple virtual functions to be implemented elsewhere. In this case, I have only two derived class -- Sphere and Triangle, both of which implement the missing member functions. Finally, I have a Parser class, which is full of static methods that do the actual "Ray Tracing" part. Here's a couple snippets for relevant portions void Parser::trace(Camera cam, Scene scene, string outputFile, int maxDepth) { int width = cam.getNumXPixels(); int height = cam.getNumYPixels(); vector<vector<vec3>> colors; colors.clear(); for (int i = 0; i< width; i++) { vector<vec3> ys; for (int j = 0; j<height; j++) { Intersection intrsct; Ray ray; cam.getRay(ray, i, j); vec3 color; printf("Obtaining color for Ray[%d,%d]\n", i,j); getColor(color, scene, ray, maxDepth); ys.push_back(color); } colors.push_back(ys); } printImage(colors, width, height, outputFile); } void Parser::getColor(vec3& color, Scene scene, Ray ray, int numBounces) { Intersection inter; scene.intersect(inter,ray); if(inter.isIntersecting()){ Color c; inter.getColor(c); c.getAmbient(color); } else { color = vec3(0,0,0); } } Right now, I've forgone the true Ray Tracing part and instead simply return the color of the first object hit, if any. As you have no doubt noticed, the only way the computer knows that a ray has intersected an object is through Scene.intersect(), which I also include. void Scene::intersect(Intersection& i, Ray r) { Intersection result; result.setDistance(numeric_limits<double>::infinity()); result.setIsIntersecting(false); double oldDist; result.getDistance(oldDist); /* Cycle through all objects, making result the closest one */ for(int ind=0; ind<objects.size(); ind++){ SceneObject* thisObj = objects[ind]; Intersection betterIntersect; thisObj->intersect(betterIntersect, r); double newDist; betterIntersect.getDistance(newDist); if (newDist < oldDist){ result = betterIntersect; oldDist = newDist; } } i = result; } Alright, now for the problem. I begin by creating a scene and filling it with objects outside of the Parser::trace() method. Now for some odd reason, I cast Ray for i=j=0 and everything works wonderfully. However, by the time the second ray is cast all of the objects stored in my Scene no longer recognize their vfptr's! I stepped through the code with a debugger and found that the information to all the vfptr's are lost somewhere between the end of getColor() and the continuation of the loop. However, if I change the arguments of getColor() to use a Scene& instead of a Scene, then no loss occurs. What crazy voodoo is this?

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  • click buttons error

    - by sara
    I will retrieve student information (id -number- name) from a database (MySQL) as a list view, each student have 2 buttons (delete - alert ) and radio buttons Every thing is ok, but how can I make an onClickListener, for example for the delete button because I try lots of examples, I heard that I can use (custom list or get view or direct onClickListener as in my code (but it is not working ) or Simple Cursor Adapter) I do not know what to use, I looked around for examples that can help me, but in my case but I did not find any so I hope this be reference for anyone have the same problem. this is my code which I use direct onClick with Simple Adapter public class ManageSection extends ListActivity { //ProgresogressDialog pDialog; private ProgressDialog pDialog; // Creating JSON Parser object // Creating JSON Parser object JSONParser jParser = new JSONParser(); //class boolean x =true; Button delete; ArrayList<HashMap<String, String>> studentList; //url to get all products list private static String url_all_student = "http://10.0.2.2/SmsPhp/view_student_info.php"; String cl; // JSON Node names private static final String TAG_SUCCESS = "success"; private static final String TAG_student = "student"; private static final String TAG_StudentID = "StudentID"; private static final String TAG_StudentNo = "StudentNo"; private static final String TAG_FullName = "FullName"; private static final String TAG_Avatar="Avatar"; HashMap<String, String> selected_student; // course JSONArray JSONArray student = null; @Override public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.manage_section); studentList = new ArrayList<HashMap<String, String>>(); ListView list1 = getListView(); list1.setAdapter(getListAdapter()); list1.setOnItemClickListener(new OnItemClickListener() { @Override public void onItemClick(AdapterView<?> adapterView, View view, int pos, long l) { selected_student =(HashMap<String, String>) studentList.get(pos); //member of your activity. delete =(Button)view.findViewById(R.id.DeleteStudent); cl=selected_student.get(TAG_StudentID); Toast.makeText(getBaseContext(),cl,Toast.LENGTH_LONG).show(); delete.setOnClickListener(new View.OnClickListener() { public void onClick(View v) { Log.d("id: ",cl); Toast.makeText(getBaseContext(),cl,Toast.LENGTH_LONG).show(); } }); } }); new LoadAllstudent().execute(); } /** * Background Async Task to Load all student by making HTTP Request * */ class LoadAllstudent extends AsyncTask<String, String, String> { /** * Before starting background thread Show Progress Dialog * */ @Override protected void onPreExecute() { super.onPreExecute(); pDialog = new ProgressDialog(ManageSection.this); pDialog.setMessage("Loading student. Please wait..."); pDialog.setIndeterminate(false); } /** * getting All student from u r l * */ @Override protected String doInBackground(String... args) { // Building Parameters List<NameValuePair> params = new ArrayList<NameValuePair>(); // getting JSON string from URL JSONObject json = jParser.makeHttpRequest(url_all_student, "GET", params); // Check your log cat for JSON response Log.d("All student : ", json.toString()); try { // Checking for SUCCESS TAG int success = json.getInt(TAG_SUCCESS); if (success == 1) { // student found // Getting Array of course student = json.getJSONArray(TAG_student); // looping through All courses for (int i = 0; i < student.length(); i++)//course JSONArray { JSONObject c = student.getJSONObject(i); // read first // Storing each json item in variable String StudentID = c.getString(TAG_StudentID); String StudentNo = c.getString(TAG_StudentNo); String FullName = c.getString(TAG_FullName); // String Avatar = c.getString(TAG_Avatar); // creating new HashMap HashMap<String, String> map = new HashMap<String, String>(); // adding each child node to HashMap key => value map.put(TAG_StudentID, StudentID); map.put(TAG_StudentNo, StudentNo); map.put(TAG_FullName, FullName); // adding HashList to ArrayList studentList.add(map); } } else { x=false; } } catch (JSONException e) { e.printStackTrace(); } return null; } /** * After completing background task Dismiss the progress dialog * **/ protected void onPostExecute(String file_url) { // dismiss the dialog after getting all products pDialog.dismiss(); if (x==false) Toast.makeText(getBaseContext(),"no student" ,Toast.LENGTH_LONG).show(); ListAdapter adapter = new SimpleAdapter( ManageSection.this, studentList, R.layout.list_student, new String[] { TAG_StudentID, TAG_StudentNo,TAG_FullName}, new int[] { R.id.StudentID, R.id.StudentNo,R.id.FullName}); setListAdapter(adapter); // Updating parsed JSON data into ListView } } } So what do you think, why doesn't the delete button work? There is no error in my log cat. What is the alternative way ?.. what should I do ?

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  • Server Error in '/' Application (ASP.NET)

    - by baeltazor
    Hi All I just setup up member ship roles and registration on my website with visual web developer using the tutorial on msdn. It works perfectly locally, but when i uploaded it to my server, I get the following page: "Server Error in '/' Application. -------------------------------------------------------------------------------- Configuration Error Description: An error occurred during the processing of a configuration file required to service this request. Please review the specific error details below and modify your configuration file appropriately. Parser Error Message: The connection name 'LocalSqlServer' was not found in the applications configuration or the connection string is empty. Source Error: [No relevant source lines] Source File: machine.config Line: 160 -------------------------------------------------------------------------------- Version Information: Microsoft .NET Framework Version:2.0.50727.4200; ASP.NET Version:2.0.50727.4016 " Does anybody know why I'm seeing this and how I may go about fixinf this? Any help is greatly appreciated. Thank you Bael. EDIT: I have just looked at my web.config file after reading the following line in the error message: "The connection name 'LocalSqlServer' was not found in the applications configuration or the connection string is empty." ... And have noticed that the following element is completely empty: <connectionStrings/> // Is this one supposed to be empty? if not what should go here? In the error it implies it shouldn't be empty. Also, I don't know where I should place LocalSqlServer LATEST EDIT After changing DataSource to LocalHost i get the following error: Server Error in '/JTS' Application. -------------------------------------------------------------------------------- A network-related or instance-specific error occurred while establishing a connection to SQL Server. The server was not found or was not accessible. Verify that the instance name is correct and that SQL Server is configured to allow remote connections. (provider: Named Pipes Provider, error: 40 - Could not open a connection to SQL Server) Description: An unhandled exception occurred during the execution of the current web request. Please review the stack trace for more information about the error and where it originated in the code. Exception Details: System.Data.SqlClient.SqlException: A network-related or instance-specific error occurred while establishing a connection to SQL Server. The server was not found or was not accessible. Verify that the instance name is correct and that SQL Server is configured to allow remote connections. (provider: Named Pipes Provider, error: 40 - Could not open a connection to SQL Server) Source Error: An unhandled exception was generated during the execution of the current web request. Information regarding the origin and location of the exception can be identified using the exception stack trace below. Stack Trace: [SqlException (0x80131904): A network-related or instance-specific error occurred while establishing a connection to SQL Server. The server was not found or was not accessible. Verify that the instance name is correct and that SQL Server is configured to allow remote connections. (provider: Named Pipes Provider, error: 40 - Could not open a connection to SQL Server)] System.Data.SqlClient.SqlInternalConnection.OnError(SqlException exception, Boolean breakConnection) +4849015 System.Data.SqlClient.TdsParser.ThrowExceptionAndWarning(TdsParserStateObject stateObj) +194 System.Data.SqlClient.TdsParser.Connect(ServerInfo serverInfo, SqlInternalConnectionTds connHandler, Boolean ignoreSniOpenTimeout, Int64 timerExpire, Boolean encrypt, Boolean trustServerCert, Boolean integratedSecurity, SqlConnection owningObject) +4862333 System.Data.SqlClient.SqlInternalConnectionTds.AttemptOneLogin(ServerInfo serverInfo, String newPassword, Boolean ignoreSniOpenTimeout, Int64 timerExpire, SqlConnection owningObject) +90 System.Data.SqlClient.SqlInternalConnectionTds.LoginNoFailover(String host, String newPassword, Boolean redirectedUserInstance, SqlConnection owningObject, SqlConnectionString connectionOptions, Int64 timerStart) +342 System.Data.SqlClient.SqlInternalConnectionTds.OpenLoginEnlist(SqlConnection owningObject, SqlConnectionString connectionOptions, String newPassword, Boolean redirectedUserInstance) +221 System.Data.SqlClient.SqlInternalConnectionTds..ctor(DbConnectionPoolIdentity identity, SqlConnectionString connectionOptions, Object providerInfo, String newPassword, SqlConnection owningObject, Boolean redirectedUserInstance) +189 System.Data.SqlClient.SqlConnectionFactory.CreateConnection(DbConnectionOptions options, Object poolGroupProviderInfo, DbConnectionPool pool, DbConnection owningConnection) +185 System.Data.ProviderBase.DbConnectionFactory.CreatePooledConnection(DbConnection owningConnection, DbConnectionPool pool, DbConnectionOptions options) +31 System.Data.ProviderBase.DbConnectionPool.CreateObject(DbConnection owningObject) +433 System.Data.ProviderBase.DbConnectionPool.UserCreateRequest(DbConnection owningObject) +66 System.Data.ProviderBase.DbConnectionPool.GetConnection(DbConnection owningObject) +499 System.Data.ProviderBase.DbConnectionFactory.GetConnection(DbConnection owningConnection) +65 System.Data.ProviderBase.DbConnectionClosed.OpenConnection(DbConnection outerConnection, DbConnectionFactory connectionFactory) +117 System.Data.SqlClient.SqlConnection.Open() +122 System.Web.DataAccess.SqlConnectionHolder.Open(HttpContext context, Boolean revertImpersonate) +87 System.Web.DataAccess.SqlConnectionHelper.GetConnection(String connectionString, Boolean revertImpersonation) +221 System.Web.Security.SqlMembershipProvider.GetPasswordWithFormat(String username, Boolean updateLastLoginActivityDate, Int32& status, String& password, Int32& passwordFormat, String& passwordSalt, Int32& failedPasswordAttemptCount, Int32& failedPasswordAnswerAttemptCount, Boolean& isApproved, DateTime& lastLoginDate, DateTime& lastActivityDate) +815 System.Web.Security.SqlMembershipProvider.CheckPassword(String username, String password, Boolean updateLastLoginActivityDate, Boolean failIfNotApproved, String& salt, Int32& passwordFormat) +105 System.Web.Security.SqlMembershipProvider.CheckPassword(String username, String password, Boolean updateLastLoginActivityDate, Boolean failIfNotApproved) +42 System.Web.Security.SqlMembershipProvider.ValidateUser(String username, String password) +78 System.Web.UI.WebControls.Login.AuthenticateUsingMembershipProvider(AuthenticateEventArgs e) +60 System.Web.UI.WebControls.Login.OnAuthenticate(AuthenticateEventArgs e) +119 System.Web.UI.WebControls.Login.AttemptLogin() +115 System.Web.UI.WebControls.Login.OnBubbleEvent(Object source, EventArgs e) +101 System.Web.UI.Control.RaiseBubbleEvent(Object source, EventArgs args) +37 System.Web.UI.WebControls.Button.OnCommand(CommandEventArgs e) +118 System.Web.UI.WebControls.Button.RaisePostBackEvent(String eventArgument) +166 System.Web.UI.WebControls.Button.System.Web.UI.IPostBackEventHandler.RaisePostBackEvent(String eventArgument) +10 System.Web.UI.Page.RaisePostBackEvent(IPostBackEventHandler sourceControl, String eventArgument) +13 System.Web.UI.Page.RaisePostBackEvent(NameValueCollection postData) +36 System.Web.UI.Page.ProcessRequestMain(Boolean includeStagesBeforeAsyncPoint, Boolean includeStagesAfterAsyncPoint) +1565 -------------------------------------------------------------------------------- Version Information: Microsoft .NET Framework Version:2.0.50727.4927; ASP.NET Version:2.0.50727.4927

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  • libcurl - unable to download a file

    - by marmistrz
    I'm working on a program which will download lyrics from sites like AZLyrics. I'm using libcurl. It's my code lyricsDownloader.cpp #include "lyricsDownloader.h" #include <curl/curl.h> #include <cstring> #include <iostream> #define DEBUG 1 ///////////////////////////////////////////////////////////////////////////// size_t lyricsDownloader::write_data_to_var(char *ptr, size_t size, size_t nmemb, void *userdata) // this function is a static member function { ostringstream * stream = (ostringstream*) userdata; size_t count = size * nmemb; stream->write(ptr, count); return count; } string AZLyricsDownloader::toProviderCode() const { /*this creates an url*/ } CURLcode AZLyricsDownloader::download() { CURL * handle; CURLcode err; ostringstream buff; handle = curl_easy_init(); if (! handle) return static_cast<CURLcode>(-1); // set verbose if debug on curl_easy_setopt( handle, CURLOPT_VERBOSE, DEBUG ); curl_easy_setopt( handle, CURLOPT_URL, toProviderCode().c_str() ); // set the download url to the generated one curl_easy_setopt(handle, CURLOPT_WRITEDATA, &buff); curl_easy_setopt(handle, CURLOPT_WRITEFUNCTION, &AZLyricsDownloader::write_data_to_var); err = curl_easy_perform(handle); // The segfault should be somewhere here - after calling the function but before it ends cerr << "cleanup\n"; curl_easy_cleanup(handle); // copy the contents to text variable lyrics = buff.str(); return err; } main.cpp #include <QString> #include <QTextEdit> #include <iostream> #include "lyricsDownloader.h" int main(int argc, char *argv[]) { AZLyricsDownloader dl(argv[1], argv[2]); dl.perform(); QTextEdit qtexted(QString::fromStdString(dl.lyrics)); cout << qPrintable(qtexted.toPlainText()); return 0; } When running ./maelyrica Anthrax Madhouse I'm getting this logged from curl * About to connect() to azlyrics.com port 80 (#0) * Trying 174.142.163.250... * connected * Connected to azlyrics.com (174.142.163.250) port 80 (#0) > GET /lyrics/anthrax/madhouse.html HTTP/1.1 Host: azlyrics.com Accept: */* < HTTP/1.1 301 Moved Permanently < Server: nginx/1.0.12 < Date: Thu, 05 Jul 2012 16:59:21 GMT < Content-Type: text/html < Content-Length: 185 < Connection: keep-alive < Location: http://www.azlyrics.com/lyrics/anthrax/madhouse.html < Segmentation fault Strangely, the file is there. The same error is displayed when there's no such page (redirect to azlyrics.com mainpage) What am I doing wrong? Thanks in advance EDIT: I made the function for writing data static, but this changes nothing. Even wget seems to have problems $ wget http://www.azlyrics.com/lyrics/anthrax/madhouse.html --2012-07-06 10:36:05-- http://www.azlyrics.com/lyrics/anthrax/madhouse.html Resolving www.azlyrics.com... 174.142.163.250 Connecting to www.azlyrics.com|174.142.163.250|:80... connected. HTTP request sent, awaiting response... No data received. Retrying. Why does opening the page in a browser work and wget/curl not? EDIT2: After adding this: curl_easy_setopt(handle, CURLOPT_FOLLOWLOCATION, 1); The log is: * About to connect() to azlyrics.com port 80 (#0) * Trying 174.142.163.250... * connected * Connected to azlyrics.com (174.142.163.250) port 80 (#0) > GET /lyrics/anthrax/madhouse.html HTTP/1.1 Host: azlyrics.com Accept: */* < HTTP/1.1 301 Moved Permanently < Server: nginx/1.0.12 < Date: Fri, 06 Jul 2012 09:09:47 GMT < Content-Type: text/html < Content-Length: 185 < Connection: keep-alive < Location: http://www.azlyrics.com/lyrics/anthrax/madhouse.html < * Ignoring the response-body * Connection #0 to host azlyrics.com left intact * Issue another request to this URL: 'http://www.azlyrics.com/lyrics/anthrax/madhouse.html' * About to connect() to www.azlyrics.com port 80 (#1) * Trying 174.142.163.250... * connected * Connected to www.azlyrics.com (174.142.163.250) port 80 (#1) > GET /lyrics/anthrax/madhouse.html HTTP/1.1 Host: www.azlyrics.com Accept: */* < HTTP/1.1 200 OK < Server: nginx/1.0.12 < Date: Fri, 06 Jul 2012 09:09:47 GMT < Content-Type: text/html < Transfer-Encoding: chunked < Connection: keep-alive < Segmentation fault

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  • Qt C++ signals and slots did not fire

    - by Xegara
    I have programmed Qt a couple of times already and I really like the signals and slots feature. But now, I guess I'm having a problem when a signal is emitted from one thread, the corresponding slot from another thread is not fired. The connection was made in the main program. This is also my first time to use Qt for ROS which uses CMake. The signal fired by the QThread triggered their corresponding slots but the emitted signal of my class UserInput did not trigger the slot in tflistener where it supposed to. I have tried everything I can. Any help? The code is provided below. Main.cpp #include <QCoreApplication> #include <QThread> #include "userinput.h" #include "tfcompleter.h" int main(int argc, char** argv) { QCoreApplication app(argc, argv); QThread *thread1 = new QThread(); QThread *thread2 = new QThread(); UserInput *input1 = new UserInput(); TfCompleter *completer = new TfCompleter(); QObject::connect(input1, SIGNAL(togglePause2()), completer, SLOT(toggle())); QObject::connect(thread1, SIGNAL(started()), completer, SLOT(startCounting())); QObject::connect(thread2, SIGNAL(started()), input1, SLOT(start())); completer->moveToThread(thread1); input1->moveToThread(thread2); thread1->start(); thread2->start(); app.exec(); return 0; } What I want to do is.. There are two seperate threads. One thread is for the user input. When the user enters [space], the thread emits a signal to toggle the boolean member field of the other thread. The other thread 's task is to just continue its process if the user wants it to run, otherwise, the user does not want it to run. I wanted to grant the user to toggle the processing anytime that he wants, that's why I decided to bring them into seperate threads. The following codes are the tflistener and userinput. tfcompleter.h #ifndef TFCOMPLETER_H #define TFCOMPLETER_H #include <QObject> #include <QtCore> class TfCompleter : public QObject { Q_OBJECT private: bool isCount; public Q_SLOTS: void toggle(); void startCounting(); }; #endif tflistener.cpp #include "tfcompleter.h" #include <iostream> void TfCompleter::startCounting() { static uint i = 0; while(true) { if(isCount) std::cout << i++ << std::endl; } } void TfCompleter::toggle() { // isCount = ~isCount; std::cout << "isCount " << std::endl; } UserInput.h #ifndef USERINPUT_H #define USERINPUT_H #include <QObject> #include <QtCore> class UserInput : public QObject { Q_OBJECT public Q_SLOTS: void start(); // Waits for the keypress from the user and emits the corresponding signal. public: Q_SIGNALS: void togglePause2(); }; #endif UserInput.cpp #include "userinput.h" #include <iostream> #include <cstdio> // Implementation of getch #include <termios.h> #include <unistd.h> /* reads from keypress, doesn't echo */ int getch(void) { struct termios oldattr, newattr; int ch; tcgetattr( STDIN_FILENO, &oldattr ); newattr = oldattr; newattr.c_lflag &= ~( ICANON | ECHO ); tcsetattr( STDIN_FILENO, TCSANOW, &newattr ); ch = getchar(); tcsetattr( STDIN_FILENO, TCSANOW, &oldattr ); return ch; } void UserInput::start() { char c = 0; while (true) { c = getch(); if (c == ' ') { Q_EMIT togglePause2(); std::cout << "SPACE" << std::endl; } c = 0; } } Here is the CMakeLists.txt. I just placed it here also since I don't know maybe the CMake has also a factor here. CMakeLists.txt ############################################################################## # CMake ############################################################################## cmake_minimum_required(VERSION 2.4.6) ############################################################################## # Ros Initialisation ############################################################################## include($ENV{ROS_ROOT}/core/rosbuild/rosbuild.cmake) rosbuild_init() set(CMAKE_AUTOMOC ON) #set the default path for built executables to the "bin" directory set(EXECUTABLE_OUTPUT_PATH ${PROJECT_SOURCE_DIR}/bin) #set the default path for built libraries to the "lib" directory set(LIBRARY_OUTPUT_PATH ${PROJECT_SOURCE_DIR}/lib) # Set the build type. Options are: # Coverage : w/ debug symbols, w/o optimization, w/ code-coverage # Debug : w/ debug symbols, w/o optimization # Release : w/o debug symbols, w/ optimization # RelWithDebInfo : w/ debug symbols, w/ optimization # MinSizeRel : w/o debug symbols, w/ optimization, stripped binaries #set(ROS_BUILD_TYPE Debug) ############################################################################## # Qt Environment ############################################################################## # Could use this, but qt-ros would need an updated deb, instead we'll move to catkin # rosbuild_include(qt_build qt-ros) rosbuild_find_ros_package(qt_build) include(${qt_build_PACKAGE_PATH}/qt-ros.cmake) rosbuild_prepare_qt4(QtCore) # Add the appropriate components to the component list here ADD_DEFINITIONS(-DQT_NO_KEYWORDS) ############################################################################## # Sections ############################################################################## #file(GLOB QT_FORMS RELATIVE ${CMAKE_CURRENT_SOURCE_DIR} ui/*.ui) #file(GLOB QT_RESOURCES RELATIVE ${CMAKE_CURRENT_SOURCE_DIR} resources/*.qrc) file(GLOB_RECURSE QT_MOC RELATIVE ${CMAKE_CURRENT_SOURCE_DIR} FOLLOW_SYMLINKS include/rgbdslam_client/*.hpp) #QT4_ADD_RESOURCES(QT_RESOURCES_CPP ${QT_RESOURCES}) #QT4_WRAP_UI(QT_FORMS_HPP ${QT_FORMS}) QT4_WRAP_CPP(QT_MOC_HPP ${QT_MOC}) ############################################################################## # Sources ############################################################################## file(GLOB_RECURSE QT_SOURCES RELATIVE ${CMAKE_CURRENT_SOURCE_DIR} FOLLOW_SYMLINKS src/*.cpp) ############################################################################## # Binaries ############################################################################## rosbuild_add_executable(rgbdslam_client ${QT_SOURCES} ${QT_MOC_HPP}) #rosbuild_add_executable(rgbdslam_client ${QT_SOURCES} ${QT_RESOURCES_CPP} ${QT_FORMS_HPP} ${QT_MOC_HPP}) target_link_libraries(rgbdslam_client ${QT_LIBRARIES})

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  • ruby on rails has_many through relationship

    - by BennyB
    Hi i'm having a little trouble with a has_many through relationship for my app and was hoping to find some help. So i've got Users & Lectures. Lectures are created by one user but then other users can then "join" the Lectures that have been created. Users have their own profile feed of the Lectures they have created & also have a feed of Lectures friends have created. This question however is not about creating a lecture but rather "Joining" a lecture that has been created already. I've created a "lecturerelationships" model & controller to handle this relationship between Lectures & the Users who have Joined (which i call "actives"). Users also then MUST "Exit" the Lecture (either by clicking "Exit" or navigating to one of the header navigation links). I'm grateful if anyone can work through some of this with me... I've got: Users.rb model Lectures.rb model Users_controller Lectures_controller then the following model lecturerelationship.rb class lecturerelationship < ActiveRecord::Base attr_accessible :active_id, :joinedlecture_id belongs_to :active, :class_name => "User" belongs_to :joinedlecture, :class_name => "Lecture" validates :active_id, :presence => true validates :joinedlecture_id, :presence => true end lecturerelationships_controller.rb class LecturerelationshipsController < ApplicationController before_filter :signed_in_user def create @lecture = Lecture.find(params[:lecturerelationship][:joinedlecture_id]) current_user.join!(@lecture) redirect_to @lecture end def destroy @lecture = Lecturerelationship.find(params[:id]).joinedlecture current_user.exit!(@user) redirect_to @user end end Lectures that have been created (by friends) show up on a users feed in the following file _activity_item.html.erb <li id="<%= activity_item.id %>"> <%= link_to gravatar_for(activity_item.user, :size => 200), activity_item.user %><br clear="all"> <%= render :partial => 'shared/join', :locals => {:activity_item => activity_item} %> <span class="title"><%= link_to activity_item.title, lecture_url(activity_item) %></span><br clear="all"> <span class="user"> Joined by <%= link_to activity_item.user.name, activity_item.user %> </span><br clear="all"> <span class="timestamp"> <%= time_ago_in_words(activity_item.created_at) %> ago. </span> <% if current_user?(activity_item.user) %> <%= link_to "delete", activity_item, :method => :delete, :confirm => "Are you sure?", :title => activity_item.content %> <% end %> </li> Then you see I link to the the 'shared/join' partial above which can be seen in the file below _join.html.erb <%= form_for(current_user.lecturerelationships.build(:joinedlecture_id => activity_item.id)) do |f| %> <div> <%= f.hidden_field :joinedlecture_id %> </div> <%= f.submit "Join", :class => "btn btn-large btn-info" %> <% end %> Some more files that might be needed: config/routes.rb SampleApp::Application.routes.draw do resources :users do member do get :following, :followers, :joined_lectures end end resources :sessions, :only => [:new, :create, :destroy] resources :lectures, :only => [:create, :destroy, :show] resources :relationships, :only => [:create, :destroy] #for users following each other resources :lecturerelationships, :only => [:create, :destroy] #users joining existing lectures So what happens is the lecture comes in my activity_feed with a Join button option at the bottom...which should create a lecturerelationship of an "active" & "joinedlecture" (which obviously are supposed to be coming from the user & lecture classes. But the error i get when i click the join button is as follows: ActiveRecord::StatementInvalid in LecturerelationshipsController#create SQLite3::ConstraintException: constraint failed: INSERT INTO "lecturerelationships" ("active_id", "created_at", "joinedlecture_id", "updated_at") VALUES (?, ?, ?, ?) Also i've included my user model (seems the error is referring to it) user.rb class User < ActiveRecord::Base attr_accessible :email, :name, :password, :password_confirmation has_secure_password has_many :lectures, :dependent => :destroy has_many :lecturerelationships, :foreign_key => "active_id", :dependent => :destroy has_many :joined_lectures, :through => :lecturerelationships, :source => :joinedlecture before_save { |user| user.email = email.downcase } before_save :create_remember_token validates :name, :presence => true, :length => { :maximum => 50 } VALID_EMAIL_REGEX = /\A[\w+\-.]+@[a-z\d\-.]+\.[a-z]+\z/i validates :email, :presence => true, :format => { :with => VALID_EMAIL_REGEX }, :uniqueness => { :case_sensitive => false } validates :password, :presence => true, :length => { :minimum => 6 } validates :password_confirmation, :presence => true def activity # This feed is for "My Activity" - basically lectures i've started Lecture.where("user_id = ?", id) end def friendactivity Lecture.from_users_followed_by(self) end # lECTURE TO USER (JOINING) RELATIONSHIPS def joined?(selected_lecture) lecturerelationships.find_by_joinedlecture_id(selected_lecture.id) end def join!(selected_lecture) lecturerelationships.create!(:joinedlecture_id => selected_lecture.id) end def exit!(selected_lecture) lecturerelationships.find_by_joinedlecture_id(selected_lecture.id).destroy end end Thanks for any and all help - i'll be on here for a while so as mentioned i'd GREATLY appreciate someone who may have the time to work through my issues with me...

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  • rails: undefined method and form_tags

    - by SuperString
    I have this in courses.html.erb under app/views/students <% if @student.courses.count < Course.count then%> <% form_tag(course_add_student_path(@student)) do%> <%= select_tag(:course, options_from_collection_for_select(@student.unenrolled_courses, :id, :name))%> <%= submit_tag 'Enroll'%> <%end%> <%else%> <p><%=h @student.name%> is enrolled in every course. </p> <%end%> I have this in my students_controller.rb under app/controllers: def course_add @student = Student.find(params[:id]) @course = Course.find(params[:course]) unless @student.enrolled_in?(@course) @student.coursess << @course flash[:notice] = 'course added' else flash[:error] = 'course already enrolled' end redirect_to :action => courses, :id => @student end And in my routes.rb, I have: resources :students, :has_many => [:awards], :member => {:courses => :get, :course_add => :post, :course_remove => :post} However, I am getting this error: undefined method `course_add_student_path' for #<#<Class:0x105321d78>:0x1053200e0> What am I missing here? Rake routes output: students GET /students(.:format) {:action=>"index", :controller=>"students"} POST /students(.:format) {:action=>"create", :controller=>"students"} new_student GET /students/new(.:format) {:action=>"new", :controller=>"students"} edit_student GET /students/:id/edit(.:format) {:action=>"edit", :controller=>"students"} student GET /students/:id(.:format) {:action=>"show", :controller=>"students"} PUT /students/:id(.:format) {:action=>"update", :controller=>"students"} DELETE /students/:id(.:format) {:action=>"destroy", :controller=>"students"} courses GET /courses(.:format) {:action=>"index", :controller=>"courses"} POST /courses(.:format) {:action=>"create", :controller=>"courses"} new_course GET /courses/new(.:format) {:action=>"new", :controller=>"courses"} edit_course GET /courses/:id/edit(.:format) {:action=>"edit", :controller=>"courses"} course GET /courses/:id(.:format) {:action=>"show", :controller=>"courses"} PUT /courses/:id(.:format) {:action=>"update", :controller=>"courses"} DELETE /courses/:id(.:format) {:action=>"destroy", :controller=>"courses"} student_awards GET /students/:student_id/awards(.:format) {:action=>"index", :controller=>"awards"} POST /students/:student_id/awards(.:format) {:action=>"create", :controller=>"awards"} new_student_award GET /students/:student_id/awards/new(.:format) {:action=>"new", :controller=>"awards"} edit_student_award GET /students/:student_id/awards/:id/edit(.:format) {:action=>"edit", :controller=>"awards"} student_award GET /students/:student_id/awards/:id(.:format) {:action=>"show", :controller=>"awards"} PUT /students/:student_id/awards/:id(.:format) {:action=>"update", :controller=>"awards"} DELETE /students/:student_id/awards/:id(.:format) {:action=>"destroy", :controller=>"awards"} courses_student GET /students/:id/courses(.:format) {:action=>"courses", :controller=>"students"} GET /students(.:format) {:action=>"index", :controller=>"students"} POST /students(.:format) {:action=>"create", :controller=>"students"} GET /students/new(.:format) {:action=>"new", :controller=>"students"} GET /students/:id/edit(.:format) {:action=>"edit", :controller=>"students"} GET /students/:id(.:format) {:action=>"show", :controller=>"students"} PUT /students/:id(.:format) {:action=>"update", :controller=>"students"} DELETE /students/:id(.:format) {:action=>"destroy", :controller=>"students"}

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  • how can we generate the bit greater than 60000?

    - by thinthinyu
    we can now generate about 50000bits. my code cannot generate more than 60000 bit..please help me............m_B is member variable and type is CString. // LFSR_ECDlg.cpp : implementation file // #include "stdafx.h" #include "myecc.h" #include "LFSR_ECDlg.h" #include "MyClass.h" #ifdef _DEBUG #define new DEBUG_NEW #undef THIS_FILE static char THIS_FILE[] = __FILE__; #endif extern MyClass mycrv; ///////////////////////////////////////////////////////////////////////////// // LFSR_ECDlg dialog LFSR_ECDlg::LFSR_ECDlg(CWnd* pParent /*=NULL*/) : CDialog(LFSR_ECDlg::IDD, pParent) { //{{AFX_DATA_INIT(LFSR_ECDlg) m_C1 = 0; m_C2 = 0; m_B = _T(""); m_p = _T(""); m_Qty = 0; m_time = _T(""); //}}AFX_DATA_INIT } void LFSR_ECDlg::DoDataExchange(CDataExchange* pDX) { CDialog::DoDataExchange(pDX); //{{AFX_DATA_MAP(LFSR_ECDlg) DDX_Text(pDX, IDC_C1, m_C1); DDX_Text(pDX, IDC_C2, m_C2); DDX_Text(pDX, IDC_Sequence, m_B); DDX_Text(pDX, IDC_Sequence2, m_p); DDX_Text(pDX, IDC_QTY, m_Qty); DDV_MinMaxLong(pDX, m_Qty, 0, 2147483647); DDX_Text(pDX, IDC_time, m_time); //}}AFX_DATA_MAP } BEGIN_MESSAGE_MAP(LFSR_ECDlg, CDialog) //{{AFX_MSG_MAP(LFSR_ECDlg) ON_WM_SETCURSOR() ON_EN_CHANGE(IDC_Sequence, OnGeneratorLFSR) ON_MESSAGE(WM_MYPAINTMESSAGE,PaintMyCaption)//by ttyu ON_BN_CLICKED(IDC_save, Onsave) //}}AFX_MSG_MAP END_MESSAGE_MAP() ///////////////////////////////////////////////////////////////////////////// // LFSR_ECDlg message handlers bool LFSR_ECDlg::CheckDataEntry() { //if((m_Px>=mycrv.p)|(m_Py>=mycrv.p)) {AfxMessageBox("Seed [P] is invalid!");return false;}//by ttyu if((m_C1<=0) | (m_C1>mycrv.n)) {AfxMessageBox("Constant c1 is not valid!");return false;} if((m_C2<=0 )| (m_C2>mycrv.n)) {AfxMessageBox("Constant c2 is not valid!");return false;} return true; } void LFSR_ECDlg::OnOK() { UpdateData(true); static int stime,etime,dtime; CString txt; m_time=""; CTime t(CTime::GetCurrentTime()); CString txt1; txt1=""; //ms = t.GetDay(); // TODO: Add extra validation here stime=t.GetTime(); txt1.Format("%d",stime); AfxMessageBox (txt1); txt=""; if (CheckDataEntry()) OnGeneratorLFSR(); etime=t.GetTime(); CString txt2; txt2=""; txt2.Format("%d",etime); AfxMessageBox (txt2); dtime=etime-stime; txt.Format("%f",dtime); m_time+=txt; // UpdateData(false); //rtime.Format("%s, %s %d, %d.",day,month,dd,yy); //CDialog::OnOK(); } void LFSR_ECDlg::OnCancel() { // TODO: Add extra cleanup here CDialog::OnCancel(); } void LFSR_ECDlg::OnGeneratorLFSR() { // TODO: If this is a RICHEDIT control, the control will not // send this notification unless you override the CDialog::OnInitDialog() // function and call CRichEditCtrl().SetEventMask() // with the ENM_CHANGE flag ORed into the mask. // TODO: Add your control notification handler code here point P0,P1,P2; P0 = mycrv.G; P1 = mycrv.MulPoint(P0,2); int C1=m_C1, C2=m_C2, n=m_Qty, k=0; int q= (mycrv.p-1) / 2; m_p = ""; m_B = ""; CString txt; for(int i=0;i<n;i++) { txt=""; if(P0==mycrv.O) txt.Format("O"); else txt.Format("(%d, %d)",P0.x,P0.y); m_p +=txt; m_p += 13; m_p += 10; if((P0.y >= 0)&&(P0.y <= q)) m_B += "0"; else if(P0 == mycrv.O) m_B += "0"; else m_B += "1"; //m_B += 13;//by ttyu // m_B += 10;//by ttyu P2 = mycrv.AddPoints(mycrv.MulPoint(P1,C2), mycrv.MulPoint(P0,C1)); P0 = P1; P1 = P2; } } BOOL LFSR_ECDlg::OnInitDialog() { CDialog::OnInitDialog(); // TODO: Add extra initialization here //code for dlg bar CString str="LFSR_EC"; m_cap.SetCaption (str); m_cap.Install (this,WM_MYPAINTMESSAGE); ////////////////////////////// return TRUE; // return TRUE unless you set the focus to a control // EXCEPTION: OCX Property Pages should return FALSE } LRESULT LFSR_ECDlg::PaintMyCaption(WPARAM wp, LPARAM lp) { m_cap.PaintCaption(wp,lp); return 0; } BOOL LFSR_ECDlg::OnSetCursor(CWnd* pWnd, UINT nHitTest, UINT message) { // TODO: Add your message handler code here and/or call default return CDialog::OnSetCursor(pWnd, nHitTest, message); } void LFSR_ECDlg::Onsave() { this->UpdateData(); CFile bitstream; char strFilter[] = { "Stream Records (*.mpl)|*.mpl| (*.pis)|*.pis|All Files (*.*)|*.*||" }; CFileDialog FileDlg(FALSE, ".mpl", NULL, 0, strFilter); //insertion//by TTT CFile cf_object; if( FileDlg.DoModal() == IDOK ){ cf_object.Open( FileDlg.GetFileName(), CFile::modeCreate|CFile::modeWrite); //char szText[100]; //strcpy(szText, "File Write Test"); CString txt; txt=""; txt.Format("%s",m_B);//by ANO AfxMessageBox (txt);//by ANO int mB_size=m_B.GetLength(); cf_object.Write (m_B,mB_size); //insertion end /* if( FileDlg.DoModal() == IDOK ) { if( bitstream.Open(FileDlg.GetFileName(), CFile::modeCreate | CFile::modeWrite) == FALSE ) return; CArchive ar(&bitstream, CArchive::store); CString txt; txt=""; txt.Format("%s",m_B);//by ANO AfxMessageBox (txt);//by ANO //txt=m_B;//by ANO ar <<txt;//by ANO ar.Close(); } else return; bitstream.Close(); */ // TODO: Add your control notification handler code here } }

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  • problem in displays data in one page

    - by user318068
    hi ,,,,, I have a problem in the following code ... The following code works as follows displays the invites for each member so that if he had five invite from supposed to be displayed all on one page But before you code that does not function Proper image is the only display one invite on the page and until the approval or rejection of the invitation displays the invite the other .... But this is not my want to offer all on one page I wish I could solve the problem and I can view all calls in one page I think that the problem is in the order code I think that the problem is in the order code my code : <?php session_start(); if (!isset($_SESSION['user_id'])) { header("Location: login.php"); } $id=$_SESSION['user_id']; ?> <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"> <html xmlns="http://www.w3.org/1999/xhtml"> <head> <meta http-equiv="Content-Type" content="text/html; charset=utf-8" /> <title>Untitled Document</title> </head> <body> <center> <?php include("connect.php"); $sql =mysql_query("select * from ninvite where recieverMemberID ='$id' and viwed= '0'"); $num =mysql_num_rows($sql); echo $num ; if ($num>0) { while($row=mysql_fetch_array($sql)) { $sender=$row['SenderMemberID']; $room=$row['RoomID']; $sql =mysql_query("select MemberName from members where MemberID ='$sender' "); $sql1 =mysql_query("select RoomName from rooms where RoomID ='$room' "); while($row=mysql_fetch_array($sql)) {$mem =$row['MemberName']; } while($rows=mysql_fetch_array($sql1)) { $Ro =$rows['RoomName']; ?> <form action="join.php" method="post"> <label> </label> <br/> <label> <?php echo " you have invite from $mem to join $Ro"; ?> </label> <br/><br/> <label>accept</label> <input name="radio1" type="radio" value="accpet" /> <label>reject</label> <input name="radio1" type="radio" value="Reject" /><br/> <input type="submit" name="submit" value="done" /> </form> <?php } } } ?> </center> </body> </html> thanks alot. my SQl -- phpMyAdmin SQL Dump -- version 3.2.4 -- http://www.phpmyadmin.net -- Host: localhost -- Generation Time: May 07, 2010 at 12:50 ? -- Server version: 5.1.41 -- PHP Version: 5.3.1 SET SQL_MODE="NO_AUTO_VALUE_ON_ZERO"; /*!40101 SET @OLD_CHARACTER_SET_CLIENT=@@CHARACTER_SET_CLIENT /; /!40101 SET @OLD_CHARACTER_SET_RESULTS=@@CHARACTER_SET_RESULTS /; /!40101 SET @OLD_COLLATION_CONNECTION=@@COLLATION_CONNECTION /; /!40101 SET NAMES utf8 */; -- -- Database: tr -- -- Table structure for table joinroom CREATE TABLE IF NOT EXISTS joinroom ( MemberID int(10) NOT NULL, RoomID int(10) NOT NULL, PRIMARY KEY (MemberID,RoomID) ) ENGINE=MyISAM DEFAULT CHARSET=latin1; -- -- Dumping data for table joinroom INSERT INTO joinroom (MemberID, RoomID) VALUES (28, 1); -- -- Table structure for table members CREATE TABLE IF NOT EXISTS members ( MemberID int(10) unsigned NOT NULL AUTO_INCREMENT, MemberName varchar(20) CHARACTER SET utf8 COLLATE utf8_bin NOT NULL, MemberPass varchar(10) CHARACTER SET utf8 COLLATE utf8_bin NOT NULL, MemberEmail varchar(30) CHARACTER SET utf8 COLLATE utf8_bin NOT NULL, MemberLocation text CHARACTER SET utf8 COLLATE utf8_bin NOT NULL, MemberImg text CHARACTER SET utf8 COLLATE utf8_bin NOT NULL, PRIMARY KEY (MemberID) ) ENGINE=MyISAM DEFAULT CHARSET=latin1 AUTO_INCREMENT=34 ; -- -- Dumping data for table members INSERT INTO members (MemberID, MemberName, MemberPass, MemberEmail, MemberLocation, MemberImg) VALUES (28, 'marwa', '1234', '[email protected]', 'mmmmmm', 'dddddddddd'), (29, 'nora', '1234', '[email protected]', 'fffffffffffgg', 'gggggggggggggg'), (30, 'soso', '1234', '[email protected]', 'ffffffff', 'kkkkkkkkkkkkkkkkkk'), (31, 'gege', '1234', '[email protected]', 'kkkkkkkkkkkkkkkk', 'uuuuuuuuuuuuuuuuu'), (32, 'nono', '1234', '[email protected]', 'ggggggggggggaaaaa', 'aaaaaaaaaaaaaaa'), (33, 'nda', '1234', '[email protected]', 'kkkkkkkkkkkkkkkk', 'ooooooooooooooo'); -- -- Table structure for table ninvite CREATE TABLE IF NOT EXISTS ninvite ( SenderMemberID int(11) NOT NULL AUTO_INCREMENT, recieverMemberID varchar(30) NOT NULL, RoomID int(11) NOT NULL, viwed int(11) NOT NULL, PRIMARY KEY (SenderMemberID,recieverMemberID,RoomID) ) ENGINE=MyISAM DEFAULT CHARSET=latin1 AUTO_INCREMENT=33 ; -- -- Dumping data for table ninvite INSERT INTO ninvite (SenderMemberID, recieverMemberID, RoomID, viwed) VALUES (28, '33', 1, 0), (28, '32', 1, 0), (28, '31', 1, 0); /*!40101 SET CHARACTER_SET_CLIENT=@OLD_CHARACTER_SET_CLIENT /; /!40101 SET CHARACTER_SET_RESULTS=@OLD_CHARACTER_SET_RESULTS /; /!40101 SET COLLATION_CONNECTION=@OLD_COLLATION_CONNECTION */;

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  • ASP.NET MVC2 - usage of LINQ-generated class (validation problem)

    - by ile
    There are few things not clear to me about ASP.NET MV2. In database I have table Contacts with several fields, and there is an additional field XmlFields of which type is xml. In that field are stored additional description fields. There are 4 classes: Contact class which corresponds to Contact table and is defined by default when creating LINQ classes ContactListView class which inherits Contact class and has some additional properties ContactXmlView class that contains fields from XmlFields field ContactDetailsView class which merges ContactListView and ContactXmlView into one class and this one is used to display data in view pages ContactListView class has re-defined some properties from Contact class (so that I can add [Required] filter used for validation) - but I get warning message: 'ObjectTest.Models.Contacts.ContactListView.FirstName' hides inherited member 'SA.Model.Contact.FirstName'. Use the new keyword if hiding was intended. ContactDetailsView class is also used in a form when creating new contact and adding it to database. I am not sure if this is correct way, and the warning message confuses me a bit. Any advise about this? Thanks, Ile EDIT According to Jakob's instructions I tried it from scratch: [MetadataType(typeof(Person_Validation))] public partial class Person { } public class Person_Validation { [Required] string FirstName { get; set; } [Required] string LastName { get; set; } [Required] int Age { get; set; } } In Controller I have this: [HttpPost] public ActionResult Create(Person person, FormCollection collection) { if (ModelState.IsValid) { try { personRepository.Add(person); personRepository.Save(); } catch { return View(person); } } return RedirectToAction("Index"); } View: <%@ Page Title="" Language="C#" MasterPageFile="~/Views/Shared/Site.Master" Inherits="System.Web.Mvc.ViewPage<Validate.Models.Person>" %> <asp:Content ID="Content1" ContentPlaceHolderID="TitleContent" runat="server"> Create </asp:Content> <asp:Content ID="Content2" ContentPlaceHolderID="MainContent" runat="server"> <h2>Create</h2> <% using (Html.BeginForm()) {%> <%= Html.ValidationSummary(true) %> <fieldset> <legend>Fields</legend> <div class="editor-label"> <%= Html.LabelFor(model => model.FirstName) %> </div> <div class="editor-field"> <%= Html.TextBoxFor(model => model.FirstName) %> <%= Html.ValidationMessageFor(model => model.FirstName) %> </div> <div class="editor-label"> <%= Html.LabelFor(model => model.LastName) %> </div> <div class="editor-field"> <%= Html.TextBoxFor(model => model.LastName) %> <%= Html.ValidationMessageFor(model => model.LastName) %> </div> <div class="editor-label"> <%= Html.LabelFor(model => model.Age) %> </div> <div class="editor-field"> <%= Html.TextBoxFor(model => model.Age) %> <%= Html.ValidationMessageFor(model => model.Age) %> </div> <p> <input type="submit" value="Create" /> </p> </fieldset> <% } %> <div> <%= Html.ActionLink("Back to List", "Index") %> </div> </asp:Content> When posting new person with no values, nothing happens (page is just reloaded). When posting with some values, person is added to db. I have no idea what am I doing wrong.

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  • Assigning two strings together getting Access Read Violation

    - by Jay Bell
    I am trying to pass a string to a class mutator and set the private member to that string here is the code that is sending the string void parseTradePairs(Exchange::Currency *curr, std::string *response, int begin, int exit) { int start; int end; string temp; string dataResponse; CURL *tempCurl; initializeCurl(tempCurl); int location = response->find("marketid", begin); if(location <= exit) { start = location + 11; begin = response->find("label", start); end = begin - start - 3; findStrings(start, end, temp, response); getMarketInfo(tempCurl, temp, dataResponse); curr->_coin->setExch(temp); // here is the line of code that is sending the string dataResponse >> *(curr->_coin); curr->_next = new Exchange::Currency(curr, curr->_position + 1); parseTradePairs(curr->_next, response, begin, exit); } } and here is the mutator within the coin class that is receiving the string and assigning it to _exch void Coin::setExch(string exch) { _exch = exch; } I have stepped through it and made sure that exch has the string in it. "105" but soon as it hits _exch = exch; I get the reading violation. I tried passing as pointer as well. I do not believe it should go out of scope. and the string variable in the class is initialized to zero in the default constructor but again that should matter unless I am trying to read from it instead of writing to it. /* defualt constructor */ Coin::Coin() { _id = ""; _label = ""; _code= ""; _name = ""; _marketCoin = ""; _volume = 0; _last = 0; _exch = ""; } Exchange::Exchange(std::string str) { _exch = str; _currencies = new Currency; std::string pair; std::string response; CURL *curl; initializeCurl(curl); getTradePairs(curl, response); int exit = response.find_last_of("marketid"); parseTradePairs(_currencies, &response, 0, exit); } int main(void) { CURL *curl; string str; string id; Coin coin1; initializeCurl(curl); Exchange ex("cryptsy"); curl_easy_cleanup(curl); system("pause"); return 0; } class Exchange { public: typedef struct Currency { Currency(Coin *coin, Currency *next, Currency *prev, int position) : _coin(coin), _next(next), _prev(prev), _position(position) {} Currency(Currency *prev, int position) : _prev(prev), _position(position), _next(NULL), _coin(&Coin()){} Currency() : _next(NULL), _prev(NULL), _position(0) {} Coin *_coin; Currency *_next; Currency *_prev; int _position; }; /* constructor and destructor */ Exchange(); Exchange(std::string str); ~Exchange(); /* Assignment operator */ Exchange& operator =(const Exchange& copyExchange); /* Parse Cryptsy Pairs */ friend void parseTradePairs(Currency *curr, std::string *response, int begin, int exit); private: std::string _exch; Currency *_currencies; }; here is what i changed it to to fix it. typedef struct Currency { Currency(Coin *coin, Currency *next, Currency *prev, int position) : _coin(coin), _next(next), _prev(prev), _position(position) {} Currency(Currency *prev, int position) : _prev(prev), _position(position), _next(NULL), _coin(&Coin()){} Currency() { _next = NULL; _prev = NULL; _position = 0; _coin = new Coin(); } Coin *_coin; Currency *_next; Currency *_prev; int _position; };

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  • error - inherited class field undeclared according to g++

    - by infoholic_anonymous
    I have a code that has the following logic. g++ gives me the error that I have not declared n in my iterator2. What could be wrong? template <typename T> class List{ template <typename TT> class Node; Node<T> *head; /* (...) */ template <bool D> class iterator1{ protected: Node<T> n; public: iterator1( Node<T> *nn ) { n = nn } /* (...) */ }; template <bool D> class iterator2 : public iterator1<D>{ public: iterator2( Node<T> *nn ) : iterator1<D>( nn ) {} void fun( Node<T> *nn ) { n = nn; } /* (...) */ }; }; EDIT : I attach the actual header file. iterator1 would be iterable_frame and iterator2 - switchable_frame. #ifndef LST_H #define LST_H template <typename T> class List { public: template <typename TT> class Node; private: Node<T> *head; public: List() { head = new Node<T>; } ~List() { empty_list(); delete head; } List( const List &l ); inline bool is_empty() const { return head->next[0] == head; } void empty_list(); template <bool DIM> class iterable_frame { protected: Node<T> *head; Node<T> **caret; public: iterable_frame( const List &l ) { head = *(caret = &l.head); } iterable_frame( const iterable_frame &i ) { head = *(caret = i.caret); } ~iterable_frame() {} /* (...) - a few methods follow */ template <bool _DIM> friend class supervised_frame; }; template <bool DIM> class switchable_frame : public iterable_frame<DIM> { Node<T> *main_head; public: switchable_frame( const List& l ) : iterable_frame<DIM>(l) { main_head = head; } inline bool next_frame() { caret = &head->next[!DIM]; head = *caret; return head != main_head; } }; template <bool DIM> class supervised_frame { iterable_frame<DIM> sentinels; iterable_frame<DIM> cells; public: supervised_frame( const List &l ) : sentinels(l), cells(l) {} ~supervised_frame() {} /* (...) - a few methods follow */ }; template <typename TT> class Node { unsigned index[2]; TT num; Node<TT> *next[2]; public: Node( unsigned x = 0, unsigned y = 0 ) { index[0]=x; index[1]=y; next[0] = this; next[1] = this; } Node( unsigned x, unsigned y, TT d ) { index[0]=x; index[1]=y; num=d; next[0] = this; next[1] = this; } Node( const Node &n ) { index[0] = n.index[0]; index[1] = n.index[1]; num = n.num; next[0] = next[1] = this; } ~Node() {} friend class List; }; }; #include "List.cpp" #endif the exact error log is the following: In file included from main.cpp:1: List.h: In member function ‘bool List<T>::switchable_frame<DIM>::next_frame()’: List.h:77: error: ‘caret’ was not declared in this scope

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  • Building my first Javascript Application (jQuery), struggling on something

    - by Jason Wells
    I'd really appreciate recommendations on the most efficient way to approach this. I'm building a simple javascript application which displays a list of records and allows the user to edit a record by clicking an "Edit" link in the records row. The user also can click the "Add" link to pop open a dialog allowing them to add a new record. Here's a working prototype of this: http://jsfiddle.net/FfRcG/ You'll note if you click "Edit" a dialog pops up with some canned values. And, if you click "Add", a dialog pops up with empty values. I need help on how to approach two problems I believe we need to pass our index to our edit dialog and reference the values within the JSON, but I am unsure how to pass the index when the user clicks edit. It bothers me that the Edit and Add div contents are so similiar (Edit just pre populates the values). I feel like there is a more efficient way of doing this but am at a loss. Here is my code for reference $(document).ready( function(){ // Our JSON (This would actually be coming from an AJAX database call) people = { "COLUMNS":["DATEMODIFIED", "NAME","AGE"], "DATA":[ ["9/6/2012", "Person 1","32"], ["9/5/2012","Person 2","23"] ] } // Here we loop over our JSON and build our HTML (Will refactor to use templating eventually) members = people.DATA; var newcontent = '<table width=50%><tr><td>date</td><td>name</td><td>age</td><td></td></tr>'; for(var i=0;i<members.length;i++) { newcontent+= '<tr id="member'+i+'"><td>' + members[i][0] + '</td>'; newcontent+= '<td>' + members[i][1] + '</td>'; newcontent+= '<td>' + members[i][2] + '</td>'; newcontent+= '<td><a href="#" class="edit" id=edit'+i+'>Edit</a></td><td>'; } newcontent += "</table>"; $("#result").html(newcontent); // Bind a dialog to the edit link $(".edit").click( function(){ // Trigger our dialog to open $("#edit").dialog("open"); // Not sure the most efficient way to change our dialog field values $("#name").val() // ??? alert($()); return false; }); // Bind a dialog to the add link $(".edit").click( function(){ // Trigger our dialog to open $("#add").dialog("open"); return false; }); // Bind a dialog to our edit DIV $("#edit").dialog(); // Bind a dialog to our add DIV $("#add").dialog(); }); And here's the HTML <h1>People</h1> <a href="#" class="add">Add a new person</a> <!-- Where results show up --> <div id="result"></div> <!-- Here's our edit DIV - I am not clear as to the best way to pass the index in our JSON so that we can reference positions in our array to pre populate the input values. --> <div id="edit"> <form> <p>Name:<br/><input type="text" id="name" value="foo"></p> <p>Age:<br/><input type="text" id="age" value="33"></p> <input type="submit" value="Save" id="submitEdit"> </form> </div> <!-- Here's our add DIV - This layout is so similiar to our edit dialog. What is the most efficient way to handle a situation like this? --> <div id="add"> <form> <p>Name:<br/><input type="text" id="name"></p> <p>Age:<br/><input type="text" id="age"></p> <input type="submit" value="Save" id="submitEdit"> </form> </div>

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  • Cisco 800 series won't forward port

    - by sam
    Hello ServerFault, I am trying to forward port 444 from my cisco router to my Web Server (192.168.0.2). As far as I can tell, my port forwarding is configured correctly, yet no traffic will pass through on port 444. Here is my config: ! version 12.3 service config no service pad service tcp-keepalives-in service tcp-keepalives-out service timestamps debug uptime service timestamps log uptime service password-encryption no service dhcp ! hostname QUESTMOUNT ! logging buffered 16386 informational logging rate-limit 100 except warnings no logging console no logging monitor enable secret 5 -removed- ! username administrator secret 5 -removed- username manager secret 5 -removed- clock timezone NZST 12 clock summer-time NZDT recurring 1 Sun Oct 2:00 3 Sun Mar 3:00 aaa new-model ! ! aaa authentication login default local aaa authentication login userlist local aaa authentication ppp default local aaa authorization network grouplist local aaa session-id common ip subnet-zero no ip source-route no ip domain lookup ip domain name quest.local ! ! no ip bootp server ip inspect name firewall tcp ip inspect name firewall udp ip inspect name firewall cuseeme ip inspect name firewall h323 ip inspect name firewall rcmd ip inspect name firewall realaudio ip inspect name firewall streamworks ip inspect name firewall vdolive ip inspect name firewall sqlnet ip inspect name firewall tftp ip inspect name firewall ftp ip inspect name firewall icmp ip inspect name firewall sip ip inspect name firewall fragment maximum 256 timeout 1 ip inspect name firewall netshow ip inspect name firewall rtsp ip inspect name firewall skinny ip inspect name firewall http ip audit notify log ip audit po max-events 100 ip audit name intrusion info list 3 action alarm ip audit name intrusion attack list 3 action alarm drop reset no ftp-server write-enable ! ! ! ! crypto isakmp policy 1 authentication pre-share ! crypto isakmp policy 2 encr 3des authentication pre-share group 2 ! crypto isakmp client configuration group staff key 0 qS;,sc:q<skro1^, domain quest.local pool vpnclients acl 106 ! ! crypto ipsec transform-set tr-null-sha esp-null esp-sha-hmac crypto ipsec transform-set tr-des-md5 esp-des esp-md5-hmac crypto ipsec transform-set tr-des-sha esp-des esp-sha-hmac crypto ipsec transform-set tr-3des-sha esp-3des esp-sha-hmac ! crypto dynamic-map vpnusers 1 description Client to Site VPN Users set transform-set tr-des-md5 ! ! crypto map cm-cryptomap client authentication list userlist crypto map cm-cryptomap isakmp authorization list grouplist crypto map cm-cryptomap client configuration address respond crypto map cm-cryptomap 65000 ipsec-isakmp dynamic vpnusers ! ! ! ! interface Ethernet0 ip address 192.168.0.254 255.255.255.0 ip access-group 102 in ip nat inside hold-queue 100 out ! interface ATM0 no ip address no atm ilmi-keepalive dsl operating-mode auto ! interface ATM0.1 point-to-point pvc 0/100 encapsulation aal5mux ppp dialer dialer pool-member 1 ! ! interface Dialer0 bandwidth 640 ip address negotiated ip access-group 101 in no ip redirects no ip unreachables ip nat outside ip inspect firewall out ip audit intrusion in encapsulation ppp no ip route-cache no ip mroute-cache dialer pool 1 dialer-group 1 no cdp enable ppp pap sent-username -removed- password 7 -removed- ppp ipcp dns request crypto map cm-cryptomap ! ip local pool vpnclients 192.168.99.1 192.168.99.254 ip nat inside source list 105 interface Dialer0 overload ip nat inside source static tcp 192.168.0.2 444 interface Dialer0 444 ip nat inside source static tcp 192.168.0.51 9000 interface Dialer0 9000 ip nat inside source static udp 192.168.0.2 1433 interface Dialer0 1433 ip nat inside source static tcp 192.168.0.2 1433 interface Dialer0 1433 ip nat inside source static tcp 192.168.0.2 25 interface Dialer0 25 ip classless ip route 0.0.0.0 0.0.0.0 Dialer0 ip http server no ip http secure-server ! ip access-list logging interval 10 logging 192.168.0.2 access-list 1 remark The local LAN. access-list 1 permit 192.168.0.0 0.0.0.255 access-list 2 permit 192.168.0.0 access-list 2 remark Where management can be done from. access-list 2 permit 192.168.0.0 0.0.0.255 access-list 3 remark Traffic not to check for intrustion detection. access-list 3 deny 192.168.99.0 0.0.0.255 access-list 3 permit any access-list 101 remark Traffic allowed to enter the router from the Internet access-list 101 permit ip 192.168.99.0 0.0.0.255 192.168.0.0 0.0.0.255 access-list 101 deny ip 0.0.0.0 0.255.255.255 any access-list 101 deny ip 10.0.0.0 0.255.255.255 any access-list 101 deny ip 127.0.0.0 0.255.255.255 any access-list 101 deny ip 169.254.0.0 0.0.255.255 any access-list 101 deny ip 172.16.0.0 0.15.255.255 any access-list 101 deny ip 192.0.2.0 0.0.0.255 any access-list 101 deny ip 192.168.0.0 0.0.255.255 any access-list 101 deny ip 198.18.0.0 0.1.255.255 any access-list 101 deny ip 224.0.0.0 0.15.255.255 any access-list 101 deny ip any host 255.255.255.255 access-list 101 permit tcp 67.228.209.128 0.0.0.15 any eq 1433 access-list 101 permit tcp host 120.136.2.22 any eq 1433 access-list 101 permit tcp host 123.100.90.58 any eq 1433 access-list 101 permit udp 67.228.209.128 0.0.0.15 any eq 1433 access-list 101 permit udp host 120.136.2.22 any eq 1433 access-list 101 permit udp host 123.100.90.58 any eq 1433 access-list 101 permit tcp any any eq 444 access-list 101 permit tcp any any eq 9000 access-list 101 permit tcp any any eq smtp access-list 101 permit udp any any eq non500-isakmp access-list 101 permit udp any any eq isakmp access-list 101 permit esp any any access-list 101 permit tcp any any eq 1723 access-list 101 permit gre any any access-list 101 permit tcp any any eq 22 access-list 101 permit tcp any any eq telnet access-list 102 remark Traffic allowed to enter the router from the Ethernet access-list 102 permit ip any host 192.168.0.254 access-list 102 deny ip any host 192.168.0.255 access-list 102 deny udp any any eq tftp log access-list 102 permit ip 192.168.0.0 0.0.0.255 192.168.99.0 0.0.0.255 access-list 102 deny ip any 0.0.0.0 0.255.255.255 log access-list 102 deny ip any 10.0.0.0 0.255.255.255 log access-list 102 deny ip any 127.0.0.0 0.255.255.255 log access-list 102 deny ip any 169.254.0.0 0.0.255.255 log access-list 102 deny ip any 172.16.0.0 0.15.255.255 log access-list 102 deny ip any 192.0.2.0 0.0.0.255 log access-list 102 deny ip any 192.168.0.0 0.0.255.255 log access-list 102 deny ip any 198.18.0.0 0.1.255.255 log access-list 102 deny udp any any eq 135 log access-list 102 deny tcp any any eq 135 log access-list 102 deny udp any any eq netbios-ns log access-list 102 deny udp any any eq netbios-dgm log access-list 102 deny tcp any any eq 445 log access-list 102 permit ip 192.168.0.0 0.0.0.255 any access-list 102 permit ip any host 255.255.255.255 access-list 102 deny ip any any log access-list 105 remark Traffic to NAT access-list 105 deny ip 192.168.0.0 0.0.0.255 192.168.99.0 0.0.0.255 access-list 105 permit ip 192.168.0.0 0.0.0.255 any access-list 106 remark User to Site VPN Clients access-list 106 permit ip 192.168.0.0 0.0.0.255 any dialer-list 1 protocol ip permit ! line con 0 no modem enable line aux 0 line vty 0 4 access-class 2 in transport input telnet ssh transport output none ! scheduler max-task-time 5000 ! end any ideas? :)

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  • How can I resolve this one application coming up with an "You don't have permission to use the application" error?

    - by morgant
    I've got a Mac OS X 10.6 Snow Leopard Server Open Directory Master with a user who's getting Mobility & Application managed preferences from a group (the only group they're a member of). The workstation is also running Mac OS X 10.6 Snow Leopard, when the user logs in and tries to run our primary application which they're explicitly allowed to run (via the group's preferences), it says "You don't have permission to use the application 'Blah'". Now, the application is added to the group's list of always allowed applications, unsigned (so a minor difference in application version or file contents shouldn't disallow it). It even lives in a subdirectory of /Applications which is in the list of folders to allow applications. I've run into this when logging this user into new workstations and the following usually works: Log them out Remove the following files from their mobile home folder on the workstation: /Library/Managed\ Preferences/, ~/.FileSync, ~/Library/Preferences/com.apple.finder.plist, and ~/Library/Preferences/com.apple.MCX.plist. Remove the following files from their network home folder on the server: ~/.FileSync, ~/Library/Preferences/com.apple.finder.plist, and ~/Library/Preferences/com.apple.MCX.plist. Log them back in on the workstation. However, this no longer resolves the issue. Their Home Sync preferences are set (on the group) to sync ~, but not the following files (manually, at login, and at logout... no background sync here): ~/.SymAVQSFile ~/NAVMac800QSFile ~/Library ~/.FileSync ~/.account Their Preferences Sync preferences are set (also on the group) to sync ~/Library & ~/Documents/Microsoft User Data, but not the following files (also manually, at login, and at logout... no background sync): ~/.SymAVQSFile ~/.Trash ~/.Trashes ~/Documents/Microsoft User Data/Entourage Temp ~/Library/Application Support/SyncServices ~/Library/Application Support/MobileSync ~/Library/Caches ~/Library/Calendars/Calendar Cache ~/Library/Logs ~/Library/Mail/AvailableFeeds ~/Library/Mail/Envelope Index ~/Library/Preferences/Macromedia/ ~/Library/Printers ~/Library/PubSub/Database ~/Library/PubSub/Downloads ~/Library/PubSub/Feeds ~/Library/Safari/Icons.db ~/Library/Safari/HistoryIndex.sk ~/Library/iTunes/iPhone Software Updates IMAP-* Exchange-* EWS-* Mac-* ~/Library/Preferences/ByHost ~/Library/Preferences/com.apple.dock.plist ~/Library/Preferences/com.apple.sitebarlists.plist ~/Library/Application Support/4D ~/Library/Preferences/com.apple.MCX.plist ~/.FileSync ~/.account Even with ~/Library/Preferences/com.apple.MCX.plist prevented from syncing during a Preferences Sync, it still seems to show up in the network home on the server frequently. Are there any other files other than ~/Library/Preferences/com.apple.MCX.plist that contain application Managed Preferences that might be causing this one app to be showing up as not allowed? Any ideas on how ~/Library/Preferences/com.apple.MCX.plist keeps getting sync'd back up the network home folder on the server? Update: I thought I had found a workaround this morning, but it also seemed to be extremely temporary. Basically, loking at /Library/Managed\ Preferences/[shortname]/com.apple.applicationaccess.new.plist I discovered that it didn't have an entry for the application in question, but /Library/Managed\ Preferences/[shortname]/complete.plist did. Naturally, I deleted com.apple.applicationaccess.new.plist, logged in again, and it worked... on one workstation. It failed on others, and after logging out & back in a couple more times it started failing on all of them again, even after further deletions of com.apple.applicationaccess.new.plist. Oddly, com.apple.applicationaccess.new.plist & complete.plist do both contain an entry for the application in question now, but it still says it's not allowed. Further Update: Okay, so I now have a reproducible workaround which seems to be required after every reboot of the workstation: Log in as the user (you'll discover you cannot launch the application in question). Fast User Switch to the local admin account on the workstation (we always have one on every machine). From that local admin account, run sudo mcxrefresh -n 'shortname' (logging out and back in as the user in question will not work). Fast User Switch back to the user (you'll still not be allowed to run the application). Log the user out and back in (you'll now be able to run the application in question.) Fast User Switch back to the local admin account, log it out, and log back in as the user in question. If you do all that exactly as described it'll keep working through log out & log back in, but NOT through a reboot. If, after a reboot, you try something like logging in as the local admin account, running sudo mcxrefresh -n 'shortname', logging out, then logging in as the user in question, it will NOT work. Yet Another Update We don't have any computer groups in our Open Directory, so it shouldn't be getting any conflicting settings from there. I ran sudo mcxquery -format xml -user shortname -group groupname before & after performing the aforementioned process to allow the application in question to be run and the results were identical (saved the result to files & diff'd... I'm not just guessing here). One Step Forward, Half a Step Back: When the Mac OS X 10.6.5 Server update was released, we upgraded our Open Directory Master to it as the changes included the following managed preferences fixes which I hoped might address this issue: Addresses an issue that could prevent managed preferences from being applied when a user logs in on a workstation that has been idle. Fixes an issue that could prevent administrators from bypassing client management settings on a workstation. This seemed to improve the situation slightly. The application in question now usually launches without error. If, and when it does launch with the "You don't have permission to use the application" error, logging the user out and back in seems to correct it. That said, we've since had to add a couple of applications to the user's ~/Applications/ directory and those are still prevented from launching. The workstations are running Mac OS X 10.6.4, the OD Master (which the workstations are bound to) is running Mac OS 10.6.5 Server (although there are two OD Replicas still running 10.6.4 Server), and we're using Workgroup Manager 10.6.3 (which is included with the Server Admin Tools 10.6.5 upgrade) to add the applications (unsigned, as always). This time, I've caught the following in /var/log/system.log when attempting to launch one of the allowed applications from ~/Applications: Dec 22 17:36:24 hostname parentalcontrolsd[43221]: -[ActivityTracker checkApp:csFlags:] [954:username] -- *** Incoming app appears to be masquerading as white listed app and failed signature validation: /Users/username/Applications/FileMaker Pro 5.5/FileMaker Pro.app/Contents/MacOS/FileMaker Pro. Note: This may be a valid app of a different version than what was whitelisted (on a different volume?) Dec 22 17:36:24 hostname [0x0-0xa42a42].com.filemaker.filemakerpro[43304]: launch of /Users/username/Applications/FileMaker Pro 5.5/FileMaker Pro.app/Contents/MacOS/FileMaker Pro was blocked Dec 22 17:36:24 hostname com.apple.launchd.peruser.1340[6375] ([0x0-0xa42a42].com.filemaker.filemakerpro[43304]): Exited with exit code: 255 Dec 22 17:36:24 hostname parentalcontrolsd[43221]: -[ActivityTracker(Private) _removeAppFromWhiteList:] [1362:username] -- *** Couldn't find local user record Running sudo mcxquery -format xml -user username -group groupname includes the following entry for FileMaker Pro 5.5 (and appears to include a full integration of the user's application whitelist & group's application whitelist): <dict> <key>bundleID</key> <string>com.filemaker.filemakerpro</string> <key>displayName</key> <string>FileMaker Pro</string> </dict> Note the lack of <key>appID</key><data> ... </data> which seems to specify a signed application. While whitelisted directories also appear to be correctly listed in the results, they too do not actually allow the applications to be run either. What is going on here?! Where else should I be looking?

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  • How can I resolve this one application coming up with an "You don't have permission to use the application" error?

    - by morgant
    I've got a Mac OS X 10.6 Snow Leopard Server Open Directory Master with a user who's getting Mobility & Application managed preferences from a group (the only group they're a member of). The workstation is also running Mac OS X 10.6 Snow Leopard, when the user logs in and tries to run our primary application which they're explicitly allowed to run (via the group's preferences), it says "You don't have permission to use the application 'Blah'". Now, the application is added to the group's list of always allowed applications, unsigned (so a minor difference in application version or file contents shouldn't disallow it). It even lives in a subdirectory of /Applications which is in the list of folders to allow applications. I've run into this when logging this user into new workstations and the following usually works: Log them out Remove the following files from their mobile home folder on the workstation: /Library/Managed\ Preferences/, ~/.FileSync, ~/Library/Preferences/com.apple.finder.plist, and ~/Library/Preferences/com.apple.MCX.plist. Remove the following files from their network home folder on the server: ~/.FileSync, ~/Library/Preferences/com.apple.finder.plist, and ~/Library/Preferences/com.apple.MCX.plist. Log them back in on the workstation. However, this no longer resolves the issue. Their Home Sync preferences are set (on the group) to sync ~, but not the following files (manually, at login, and at logout... no background sync here): ~/.SymAVQSFile ~/NAVMac800QSFile ~/Library ~/.FileSync ~/.account Their Preferences Sync preferences are set (also on the group) to sync ~/Library & ~/Documents/Microsoft User Data, but not the following files (also manually, at login, and at logout... no background sync): ~/.SymAVQSFile ~/.Trash ~/.Trashes ~/Documents/Microsoft User Data/Entourage Temp ~/Library/Application Support/SyncServices ~/Library/Application Support/MobileSync ~/Library/Caches ~/Library/Calendars/Calendar Cache ~/Library/Logs ~/Library/Mail/AvailableFeeds ~/Library/Mail/Envelope Index ~/Library/Preferences/Macromedia/ ~/Library/Printers ~/Library/PubSub/Database ~/Library/PubSub/Downloads ~/Library/PubSub/Feeds ~/Library/Safari/Icons.db ~/Library/Safari/HistoryIndex.sk ~/Library/iTunes/iPhone Software Updates IMAP-* Exchange-* EWS-* Mac-* ~/Library/Preferences/ByHost ~/Library/Preferences/com.apple.dock.plist ~/Library/Preferences/com.apple.sitebarlists.plist ~/Library/Application Support/4D ~/Library/Preferences/com.apple.MCX.plist ~/.FileSync ~/.account Even with ~/Library/Preferences/com.apple.MCX.plist prevented from syncing during a Preferences Sync, it still seems to show up in the network home on the server frequently. Are there any other files other than ~/Library/Preferences/com.apple.MCX.plist that contain application Managed Preferences that might be causing this one app to be showing up as not allowed? Any ideas on how ~/Library/Preferences/com.apple.MCX.plist keeps getting sync'd back up the network home folder on the server? Update: I thought I had found a workaround this morning, but it also seemed to be extremely temporary. Basically, loking at /Library/Managed\ Preferences/[shortname]/com.apple.applicationaccess.new.plist I discovered that it didn't have an entry for the application in question, but /Library/Managed\ Preferences/[shortname]/complete.plist did. Naturally, I deleted com.apple.applicationaccess.new.plist, logged in again, and it worked... on one workstation. It failed on others, and after logging out & back in a couple more times it started failing on all of them again, even after further deletions of com.apple.applicationaccess.new.plist. Oddly, com.apple.applicationaccess.new.plist & complete.plist do both contain an entry for the application in question now, but it still says it's not allowed. Further Update: Okay, so I now have a reproducible workaround which seems to be required after every reboot of the workstation: Log in as the user (you'll discover you cannot launch the application in question). Fast User Switch to the local admin account on the workstation (we always have one on every machine). From that local admin account, run sudo mcxrefresh -n 'shortname' (logging out and back in as the user in question will not work). Fast User Switch back to the user (you'll still not be allowed to run the application). Log the user out and back in (you'll now be able to run the application in question.) Fast User Switch back to the local admin account, log it out, and log back in as the user in question. If you do all that exactly as described it'll keep working through log out & log back in, but NOT through a reboot. If, after a reboot, you try something like logging in as the local admin account, running sudo mcxrefresh -n 'shortname', logging out, then logging in as the user in question, it will NOT work. Yet Another Update We don't have any computer groups in our Open Directory, so it shouldn't be getting any conflicting settings from there. I ran sudo mcxquery -format xml -user shortname -group groupname before & after performing the aforementioned process to allow the application in question to be run and the results were identical (saved the result to files & diff'd... I'm not just guessing here). One Step Forward, Half a Step Back: When the Mac OS X 10.6.5 Server update was released, we upgraded our Open Directory Master to it as the changes included the following managed preferences fixes which I hoped might address this issue: Addresses an issue that could prevent managed preferences from being applied when a user logs in on a workstation that has been idle. Fixes an issue that could prevent administrators from bypassing client management settings on a workstation. This seemed to improve the situation slightly. The application in question now usually launches without error. If, and when it does launch with the "You don't have permission to use the application" error, logging the user out and back in seems to correct it. That said, we've since had to add a couple of applications to the user's ~/Applications/ directory and those are still prevented from launching. The workstations are running Mac OS X 10.6.4, the OD Master (which the workstations are bound to) is running Mac OS 10.6.5 Server (although there are two OD Replicas still running 10.6.4 Server), and we're using Workgroup Manager 10.6.3 (which is included with the Server Admin Tools 10.6.5 upgrade) to add the applications (unsigned, as always). This time, I've caught the following in /var/log/system.log when attempting to launch one of the allowed applications from ~/Applications: Dec 22 17:36:24 hostname parentalcontrolsd[43221]: -[ActivityTracker checkApp:csFlags:] [954:username] -- *** Incoming app appears to be masquerading as white listed app and failed signature validation: /Users/username/Applications/FileMaker Pro 5.5/FileMaker Pro.app/Contents/MacOS/FileMaker Pro. Note: This may be a valid app of a different version than what was whitelisted (on a different volume?) Dec 22 17:36:24 hostname [0x0-0xa42a42].com.filemaker.filemakerpro[43304]: launch of /Users/username/Applications/FileMaker Pro 5.5/FileMaker Pro.app/Contents/MacOS/FileMaker Pro was blocked Dec 22 17:36:24 hostname com.apple.launchd.peruser.1340[6375] ([0x0-0xa42a42].com.filemaker.filemakerpro[43304]): Exited with exit code: 255 Dec 22 17:36:24 hostname parentalcontrolsd[43221]: -[ActivityTracker(Private) _removeAppFromWhiteList:] [1362:username] -- *** Couldn't find local user record Running sudo mcxquery -format xml -user username -group groupname includes the following entry for FileMaker Pro 5.5 (and appears to include a full integration of the user's application whitelist & group's application whitelist): <dict> <key>bundleID</key> <string>com.filemaker.filemakerpro</string> <key>displayName</key> <string>FileMaker Pro</string> </dict> Note the lack of <key>appID</key><data> ... </data> which seems to specify a signed application. While whitelisted directories also appear to be correctly listed in the results, they too do not actually allow the applications to be run either. What is going on here?! Where else should I be looking?

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  • Scrum in 5 Minutes

    - by Stephen.Walther
    The goal of this blog entry is to explain the basic concepts of Scrum in less than five minutes. You learn how Scrum can help a team of developers to successfully complete a complex software project. Product Backlog and the Product Owner Imagine that you are part of a team which needs to create a new website – for example, an e-commerce website. You have an overwhelming amount of work to do. You need to build (or possibly buy) a shopping cart, install an SSL certificate, create a product catalog, create a Facebook page, and at least a hundred other things that you have not thought of yet. According to Scrum, the first thing you should do is create a list. Place the highest priority items at the top of the list and the lower priority items lower in the list. For example, creating the shopping cart and buying the domain name might be high priority items and creating a Facebook page might be a lower priority item. In Scrum, this list is called the Product Backlog. How do you prioritize the items in the Product Backlog? Different stakeholders in the project might have different priorities. Gary, your division VP, thinks that it is crucial that the e-commerce site has a mobile app. Sally, your direct manager, thinks taking advantage of new HTML5 features is much more important. Multiple people are pulling you in different directions. According to Scrum, it is important that you always designate one person, and only one person, as the Product Owner. The Product Owner is the person who decides what items should be added to the Product Backlog and the priority of the items in the Product Backlog. The Product Owner could be the customer who is paying the bills, the project manager who is responsible for delivering the project, or a customer representative. The critical point is that the Product Owner must always be a single person and that single person has absolute authority over the Product Backlog. Sprints and the Sprint Backlog So now the developer team has a prioritized list of items and they can start work. The team starts implementing the first item in the Backlog — the shopping cart — and the team is making good progress. Unfortunately, however, half-way through the work of implementing the shopping cart, the Product Owner changes his mind. The Product Owner decides that it is much more important to create the product catalog before the shopping cart. With some frustration, the team switches their developmental efforts to focus on implementing the product catalog. However, part way through completing this work, once again the Product Owner changes his mind about the highest priority item. Getting work done when priorities are constantly shifting is frustrating for the developer team and it results in lower productivity. At the same time, however, the Product Owner needs to have absolute authority over the priority of the items which need to get done. Scrum solves this conflict with the concept of Sprints. In Scrum, a developer team works in Sprints. At the beginning of a Sprint the developers and the Product Owner agree on the items from the backlog which they will complete during the Sprint. This subset of items from the Product Backlog becomes the Sprint Backlog. During the Sprint, the Product Owner is not allowed to change the items in the Sprint Backlog. In other words, the Product Owner cannot shift priorities on the developer team during the Sprint. Different teams use Sprints of different lengths such as one month Sprints, two-week Sprints, and one week Sprints. For high-stress, time critical projects, teams typically choose shorter sprints such as one week sprints. For more mature projects, longer one month sprints might be more appropriate. A team can pick whatever Sprint length makes sense for them just as long as the team is consistent. You should pick a Sprint length and stick with it. Daily Scrum During a Sprint, the developer team needs to have meetings to coordinate their work on completing the items in the Sprint Backlog. For example, the team needs to discuss who is working on what and whether any blocking issues have been discovered. Developers hate meetings (well, sane developers hate meetings). Meetings take developers away from their work of actually implementing stuff as opposed to talking about implementing stuff. However, a developer team which never has meetings and never coordinates their work also has problems. For example, Fred might get stuck on a programming problem for days and never reach out for help even though Tom (who sits in the cubicle next to him) has already solved the very same problem. Or, both Ted and Fred might have started working on the same item from the Sprint Backlog at the same time. In Scrum, these conflicting needs – limiting meetings but enabling team coordination – are resolved with the idea of the Daily Scrum. The Daily Scrum is a meeting for coordinating the work of the developer team which happens once a day. To keep the meeting short, each developer answers only the following three questions: 1. What have you done since yesterday? 2. What do you plan to do today? 3. Any impediments in your way? During the Daily Scrum, developers are not allowed to talk about issues with their cat, do demos of their latest work, or tell heroic stories of programming problems overcome. The meeting must be kept short — typically about 15 minutes. Issues which come up during the Daily Scrum should be discussed in separate meetings which do not involve the whole developer team. Stories and Tasks Items in the Product or Sprint Backlog – such as building a shopping cart or creating a Facebook page – are often referred to as User Stories or Stories. The Stories are created by the Product Owner and should represent some business need. Unlike the Product Owner, the developer team needs to think about how a Story should be implemented. At the beginning of a Sprint, the developer team takes the Stories from the Sprint Backlog and breaks the stories into tasks. For example, the developer team might take the Create a Shopping Cart story and break it into the following tasks: · Enable users to add and remote items from shopping cart · Persist the shopping cart to database between visits · Redirect user to checkout page when Checkout button is clicked During the Daily Scrum, members of the developer team volunteer to complete the tasks required to implement the next Story in the Sprint Backlog. When a developer talks about what he did yesterday or plans to do tomorrow then the developer should be referring to a task. Stories are owned by the Product Owner and a story is all about business value. In contrast, the tasks are owned by the developer team and a task is all about implementation details. A story might take several days or weeks to complete. A task is something which a developer can complete in less than a day. Some teams get lazy about breaking stories into tasks. Neglecting to break stories into tasks can lead to “Never Ending Stories” If you don’t break a story into tasks, then you can’t know how much of a story has actually been completed because you don’t have a clear idea about the implementation steps required to complete the story. Scrumboard During the Daily Scrum, the developer team uses a Scrumboard to coordinate their work. A Scrumboard contains a list of the stories for the current Sprint, the tasks associated with each Story, and the state of each task. The developer team uses the Scrumboard so everyone on the team can see, at a glance, what everyone is working on. As a developer works on a task, the task moves from state to state and the state of the task is updated on the Scrumboard. Common task states are ToDo, In Progress, and Done. Some teams include additional task states such as Needs Review or Needs Testing. Some teams use a physical Scrumboard. In that case, you use index cards to represent the stories and the tasks and you tack the index cards onto a physical board. Using a physical Scrumboard has several disadvantages. A physical Scrumboard does not work well with a distributed team – for example, it is hard to share the same physical Scrumboard between Boston and Seattle. Also, generating reports from a physical Scrumboard is more difficult than generating reports from an online Scrumboard. Estimating Stories and Tasks Stakeholders in a project, the people investing in a project, need to have an idea of how a project is progressing and when the project will be completed. For example, if you are investing in creating an e-commerce site, you need to know when the site can be launched. It is not enough to just say that “the project will be done when it is done” because the stakeholders almost certainly have a limited budget to devote to the project. The people investing in the project cannot determine the business value of the project unless they can have an estimate of how long it will take to complete the project. Developers hate to give estimates. The reason that developers hate to give estimates is that the estimates are almost always completely made up. For example, you really don’t know how long it takes to build a shopping cart until you finish building a shopping cart, and at that point, the estimate is no longer useful. The problem is that writing code is much more like Finding a Cure for Cancer than Building a Brick Wall. Building a brick wall is very straightforward. After you learn how to add one brick to a wall, you understand everything that is involved in adding a brick to a wall. There is no additional research required and no surprises. If, on the other hand, I assembled a team of scientists and asked them to find a cure for cancer, and estimate exactly how long it will take, they would have no idea. The problem is that there are too many unknowns. I don’t know how to cure cancer, I need to do a lot of research here, so I cannot even begin to estimate how long it will take. So developers hate to provide estimates, but the Product Owner and other product stakeholders, have a legitimate need for estimates. Scrum resolves this conflict by using the idea of Story Points. Different teams use different units to represent Story Points. For example, some teams use shirt sizes such as Small, Medium, Large, and X-Large. Some teams prefer to use Coffee Cup sizes such as Tall, Short, and Grande. Finally, some teams like to use numbers from the Fibonacci series. These alternative units are converted into a Story Point value. Regardless of the type of unit which you use to represent Story Points, the goal is the same. Instead of attempting to estimate a Story in hours (which is doomed to failure), you use a much less fine-grained measure of work. A developer team is much more likely to be able to estimate that a Story is Small or X-Large than the exact number of hours required to complete the story. So you can think of Story Points as a compromise between the needs of the Product Owner and the developer team. When a Sprint starts, the developer team devotes more time to thinking about the Stories in a Sprint and the developer team breaks the Stories into Tasks. In Scrum, you estimate the work required to complete a Story by using Story Points and you estimate the work required to complete a task by using hours. The difference between Stories and Tasks is that you don’t create a task until you are just about ready to start working on a task. A task is something that you should be able to create within a day, so you have a much better chance of providing an accurate estimate of the work required to complete a task than a story. Burndown Charts In Scrum, you use Burndown charts to represent the remaining work on a project. You use Release Burndown charts to represent the overall remaining work for a project and you use Sprint Burndown charts to represent the overall remaining work for a particular Sprint. You create a Release Burndown chart by calculating the remaining number of uncompleted Story Points for the entire Product Backlog every day. The vertical axis represents Story Points and the horizontal axis represents time. A Sprint Burndown chart is similar to a Release Burndown chart, but it focuses on the remaining work for a particular Sprint. There are two different types of Sprint Burndown charts. You can either represent the remaining work in a Sprint with Story Points or with task hours (the following image, taken from Wikipedia, uses hours). When each Product Backlog Story is completed, the Release Burndown chart slopes down. When each Story or task is completed, the Sprint Burndown chart slopes down. Burndown charts typically do not always slope down over time. As new work is added to the Product Backlog, the Release Burndown chart slopes up. If new tasks are discovered during a Sprint, the Sprint Burndown chart will also slope up. The purpose of a Burndown chart is to give you a way to track team progress over time. If, halfway through a Sprint, the Sprint Burndown chart is still climbing a hill then you know that you are in trouble. Team Velocity Stakeholders in a project always want more work done faster. For example, the Product Owner for the e-commerce site wants the website to launch before tomorrow. Developers tend to be overly optimistic. Rarely do developers acknowledge the physical limitations of reality. So Project stakeholders and the developer team often collude to delude themselves about how much work can be done and how quickly. Too many software projects begin in a state of optimism and end in frustration as deadlines zoom by. In Scrum, this problem is overcome by calculating a number called the Team Velocity. The Team Velocity is a measure of the average number of Story Points which a team has completed in previous Sprints. Knowing the Team Velocity is important during the Sprint Planning meeting when the Product Owner and the developer team work together to determine the number of stories which can be completed in the next Sprint. If you know the Team Velocity then you can avoid committing to do more work than the team has been able to accomplish in the past, and your team is much more likely to complete all of the work required for the next Sprint. Scrum Master There are three roles in Scrum: the Product Owner, the developer team, and the Scrum Master. I’v e already discussed the Product Owner. The Product Owner is the one and only person who maintains the Product Backlog and prioritizes the stories. I’ve also described the role of the developer team. The members of the developer team do the work of implementing the stories by breaking the stories into tasks. The final role, which I have not discussed, is the role of the Scrum Master. The Scrum Master is responsible for ensuring that the team is following the Scrum process. For example, the Scrum Master is responsible for making sure that there is a Daily Scrum meeting and that everyone answers the standard three questions. The Scrum Master is also responsible for removing (non-technical) impediments which the team might encounter. For example, if the team cannot start work until everyone installs the latest version of Microsoft Visual Studio then the Scrum Master has the responsibility of working with management to get the latest version of Visual Studio as quickly as possible. The Scrum Master can be a member of the developer team. Furthermore, different people can take on the role of the Scrum Master over time. The Scrum Master, however, cannot be the same person as the Product Owner. Using SonicAgile SonicAgile (SonicAgile.com) is an online tool which you can use to manage your projects using Scrum. You can use the SonicAgile Product Backlog to create a prioritized list of stories. You can estimate the size of the Stories using different Story Point units such as Shirt Sizes and Coffee Cup sizes. You can use SonicAgile during the Sprint Planning meeting to select the Stories that you want to complete during a particular Sprint. You can configure Sprints to be any length of time. SonicAgile calculates Team Velocity automatically and displays a warning when you add too many stories to a Sprint. In other words, it warns you when it thinks you are overcommitting in a Sprint. SonicAgile also includes a Scrumboard which displays the list of Stories selected for a Sprint and the tasks associated with each story. You can drag tasks from one task state to another. Finally, SonicAgile enables you to generate Release Burndown and Sprint Burndown charts. You can use these charts to view the progress of your team. To learn more about SonicAgile, visit SonicAgile.com. Summary In this post, I described many of the basic concepts of Scrum. You learned how a Product Owner uses a Product Backlog to create a prioritized list of tasks. I explained why work is completed in Sprints so the developer team can be more productive. I also explained how a developer team uses the daily scrum to coordinate their work. You learned how the developer team uses a Scrumboard to see, at a glance, who is working on what and the state of each task. I also discussed Burndown charts. You learned how you can use both Release and Sprint Burndown charts to track team progress in completing a project. Finally, I described the crucial role of the Scrum Master – the person who is responsible for ensuring that the rules of Scrum are being followed. My goal was not to describe all of the concepts of Scrum. This post was intended to be an introductory overview. For a comprehensive explanation of Scrum, I recommend reading Ken Schwaber’s book Agile Project Management with Scrum: http://www.amazon.com/Agile-Project-Management-Microsoft-Professional/dp/073561993X/ref=la_B001H6ODMC_1_1?ie=UTF8&qid=1345224000&sr=1-1

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  • ANTS CLR and Memory Profiler In Depth Review (Part 1 of 2 &ndash; CLR Profiler)

    - by ToStringTheory
    One of the things that people might not know about me, is my obsession to make my code as efficient as possible.  Many people might not realize how much of a task or undertaking that this might be, but it is surely a task as monumental as climbing Mount Everest, except this time it is a challenge for the mind…  In trying to make code efficient, there are many different factors that play a part – size of project or solution, tiers, language used, experience and training of the programmer, technologies used, maintainability of the code – the list can go on for quite some time. I spend quite a bit of time when developing trying to determine what is the best way to implement a feature to accomplish the efficiency that I look to achieve.  One program that I have recently come to learn about – Red Gate ANTS Performance (CLR) and Memory profiler gives me tools to accomplish that job more efficiently as well.  In this review, I am going to cover some of the features of the ANTS profiler set by compiling some hideous example code to test against. Notice As a member of the Geeks With Blogs Influencers program, one of the perks is the ability to review products, in exchange for a free license to the program.  I have not let this affect my opinions of the product in any way, and Red Gate nor Geeks With Blogs has tried to influence my opinion regarding this product in any way. Introduction The ANTS Profiler pack provided by Red Gate was something that I had not heard of before receiving an email regarding an offer to review it for a license.  Since I look to make my code efficient, it was a no brainer for me to try it out!  One thing that I have to say took me by surprise is that upon downloading the program and installing it you fill out a form for your usual contact information.  Sure enough within 2 hours, I received an email from a sales representative at Red Gate asking if she could help me to achieve the most out of my trial time so it wouldn’t go to waste.  After replying to her and explaining that I was looking to review its feature set, she put me in contact with someone that setup a demo session to give me a quick rundown of its features via an online meeting.  After having dealt with a massive ordeal with one of my utility companies and their complete lack of customer service, Red Gates friendly and helpful representatives were a breath of fresh air, and something I was thankful for. ANTS CLR Profiler The ANTS CLR profiler is the thing I want to focus on the most in this post, so I am going to dive right in now. Install was simple and took no time at all.  It installed both the profiler for the CLR and Memory, but also visual studio extensions to facilitate the usage of the profilers (click any images for full size images): The Visual Studio menu options (under ANTS menu) Starting the CLR Performance Profiler from the start menu yields this window If you follow the instructions after launching the program from the start menu (Click File > New Profiling Session to start a new project), you are given a dialog with plenty of options for profiling: The New Session dialog.  Lots of options.  One thing I noticed is that the buttons in the lower right were half-covered by the panel of the application.  If I had to guess, I would imagine that this is caused by my DPI settings being set to 125%.  This is a problem I have seen in other applications as well that don’t scale well to different dpi scales. The profiler options give you the ability to profile: .NET Executable ASP.NET web application (hosted in IIS) ASP.NET web application (hosted in IIS express) ASP.NET web application (hosted in Cassini Web Development Server) SharePoint web application (hosted in IIS) Silverlight 4+ application Windows Service COM+ server XBAP (local XAML browser application) Attach to an already running .NET 4 process Choosing each option provides a varying set of other variables/options that one can set including options such as application arguments, operating path, record I/O performance performance counters to record (43 counters in all!), etc…  All in all, they give you the ability to profile many different .Net project types, and make it simple to do so.  In most cases of my using this application, I would be using the built in Visual Studio extensions, as they automatically start a new profiling project in ANTS with the options setup, and start your program, however RedGate has made it easy enough to profile outside of Visual Studio as well. On the flip side of this, as someone who lives most of their work life in Visual Studio, one thing I do wish is that instead of opening an entirely separate application/gui to perform profiling after launching, that instead they would provide a Visual Studio panel with the information, and integrate more of the profiling project information into Visual Studio.  So, now that we have an idea of what options that the profiler gives us, its time to test its abilities and features. Horrendous Example Code – Prime Number Generator One of my interests besides development, is Physics and Math – what I went to college for.  I have especially always been interested in prime numbers, as they are something of a mystery…  So, I decided that I would go ahead and to test the abilities of the profiler, I would write a small program, website, and library to generate prime numbers in the quantity that you ask for.  I am going to start off with some terrible code, and show how I would see the profiler being used as a development tool. First off, the IPrimes interface (all code is downloadable at the end of the post): interface IPrimes { IEnumerable<int> GetPrimes(int retrieve); } Simple enough, right?  Anything that implements the interface will (hopefully) provide an IEnumerable of int, with the quantity specified in the parameter argument.  Next, I am going to implement this interface in the most basic way: public class DumbPrimes : IPrimes { public IEnumerable<int> GetPrimes(int retrieve) { //store a list of primes already found var _foundPrimes = new List<int>() { 2, 3 }; //if i ask for 1 or two primes, return what asked for if (retrieve <= _foundPrimes.Count()) return _foundPrimes.Take(retrieve); //the next number to look at int _analyzing = 4; //since I already determined I don't have enough //execute at least once, and until quantity is sufficed do { //assume prime until otherwise determined bool isPrime = true; //start dividing at 2 //divide until number is reached, or determined not prime for (int i = 2; i < _analyzing && isPrime; i++) { //if (i) goes into _analyzing without a remainder, //_analyzing is NOT prime if (_analyzing % i == 0) isPrime = false; } //if it is prime, add to found list if (isPrime) _foundPrimes.Add(_analyzing); //increment number to analyze next _analyzing++; } while (_foundPrimes.Count() < retrieve); return _foundPrimes; } } This is the simplest way to get primes in my opinion.  Checking each number by the straight definition of a prime – is it divisible by anything besides 1 and itself. I have included this code in a base class library for my solution, as I am going to use it to demonstrate a couple of features of ANTS.  This class library is consumed by a simple non-MVVM WPF application, and a simple MVC4 website.  I will not post the WPF code here inline, as it is simply an ObservableCollection<int>, a label, two textbox’s, and a button. Starting a new Profiling Session So, in Visual Studio, I have just completed my first stint developing the GUI and DumbPrimes IPrimes class, so now I want to check my codes efficiency by profiling it.  All I have to do is build the solution (surprised initiating a profiling session doesn’t do this, but I suppose I can understand it), and then click the ANTS menu, followed by Profile Performance.  I am then greeted by the profiler starting up and already monitoring my program live: You are provided with a realtime graph at the top, and a pane at the bottom giving you information on how to proceed.  I am going to start by asking my program to show me the first 15000 primes: After the program finally began responding again (I did all the work on the main UI thread – how bad!), I stopped the profiler, which did kill the process of my program too.  One important thing to note, is that the profiler by default wants to give you a lot of detail about the operation – line hit counts, time per line, percent time per line, etc…  The important thing to remember is that this itself takes a lot of time.  When running my program without the profiler attached, it can generate the 15000 primes in 5.18 seconds, compared to 74.5 seconds – almost a 1500 percent increase.  While this may seem like a lot, remember that there is a trade off.  It may be WAY more inefficient, however, I am able to drill down and make improvements to specific problem areas, and then decrease execution time all around. Analyzing the Profiling Session After clicking ‘Stop Profiling’, the process running my application stopped, and the entire execution time was automatically selected by ANTS, and the results shown below: Now there are a number of interesting things going on here, I am going to cover each in a section of its own: Real Time Performance Counter Bar (top of screen) At the top of the screen, is the real time performance bar.  As your application is running, this will constantly update with the currently selected performance counters status.  A couple of cool things to note are the fact that you can drag a selection around specific time periods to drill down the detail views in the lower 2 panels to information pertaining to only that period. After selecting a time period, you can bookmark a section and name it, so that it is easy to find later, or after reloaded at a later time.  You can also zoom in, out, or fit the graph to the space provided – useful for drilling down. It may be hard to see, but at the top of the processor time graph below the time ticks, but above the red usage graph, there is a green bar. This bar shows at what times a method that is selected in the ‘Call tree’ panel is called. Very cool to be able to click on a method and see at what times it made an impact. As I said before, ANTS provides 43 different performance counters you can hook into.  Click the arrow next to the Performance tab at the top will allow you to change between different counters if you have them selected: Method Call Tree, ADO.Net Database Calls, File IO – Detail Panel Red Gate really hit the mark here I think. When you select a section of the run with the graph, the call tree populates to fill a hierarchical tree of method calls, with information regarding each of the methods.   By default, methods are hidden where the source is not provided (framework type code), however, Red Gate has integrated Reflector into ANTS, so even if you don’t have source for something, you can select a method and get the source if you want.  Methods are also hidden where the impact is seen as insignificant – methods that are only executed for 1% of the time of the overall calling methods time; in other words, working on making them better is not where your efforts should be focused. – Smart! Source Panel – Detail Panel The source panel is where you can see line level information on your code, showing the code for the currently selected method from the Method Call Tree.  If the code is not available, Reflector takes care of it and shows the code anyways! As you can notice, there does seem to be a problem with how ANTS determines what line is the actual line that a call is completed on.  I have suspicions that this may be due to some of the inline code optimizations that the CLR applies upon compilation of the assembly.  In a method with comments, the problem is much more severe: As you can see here, apparently the most offending code in my base library was a comment – *gasp*!  Removing the comments does help quite a bit, however I hope that Red Gate works on their counter algorithm soon to improve the logic on positioning for statistics: I did a small test just to demonstrate the lines are correct without comments. For me, it isn’t a deal breaker, as I can usually determine the correct placements by looking at the application code in the region and determining what makes sense, but it is something that would probably build up some irritation with time. Feature – Suggest Method for Optimization A neat feature to really help those in need of a pointer, is the menu option under tools to automatically suggest methods to optimize/improve: Nice feature – clicking it filters the call tree and stars methods that it thinks are good candidates for optimization.  I do wish that they would have made it more visible for those of use who aren’t great on sight: Process Integration I do think that this could have a place in my process.  After experimenting with the profiler, I do think it would be a great benefit to do some development, testing, and then after all the bugs are worked out, use the profiler to check on things to make sure nothing seems like it is hogging more than its fair share.  For example, with this program, I would have developed it, ran it, tested it – it works, but slowly. After looking at the profiler, and seeing the massive amount of time spent in 1 method, I might go ahead and try to re-implement IPrimes (I actually would probably rewrite the offending code, but so that I can distribute both sets of code easily, I’m just going to make another implementation of IPrimes).  Using two pieces of knowledge about prime numbers can make this method MUCH more efficient – prime numbers fall into two buckets 6k+/-1 , and a number is prime if it is not divisible by any other primes before it: public class SmartPrimes : IPrimes { public IEnumerable<int> GetPrimes(int retrieve) { //store a list of primes already found var _foundPrimes = new List<int>() { 2, 3 }; //if i ask for 1 or two primes, return what asked for if (retrieve <= _foundPrimes.Count()) return _foundPrimes.Take(retrieve); //the next number to look at int _k = 1; //since I already determined I don't have enough //execute at least once, and until quantity is sufficed do { //assume prime until otherwise determined bool isPrime = true; int potentialPrime; //analyze 6k-1 //assign the value to potential potentialPrime = 6 * _k - 1; //if there are any primes that divise this, it is NOT a prime number //using PLINQ for quick boost isPrime = !_foundPrimes.AsParallel() .Any(prime => potentialPrime % prime == 0); //if it is prime, add to found list if (isPrime) _foundPrimes.Add(potentialPrime); if (_foundPrimes.Count() == retrieve) break; //analyze 6k+1 //assign the value to potential potentialPrime = 6 * _k + 1; //if there are any primes that divise this, it is NOT a prime number //using PLINQ for quick boost isPrime = !_foundPrimes.AsParallel() .Any(prime => potentialPrime % prime == 0); //if it is prime, add to found list if (isPrime) _foundPrimes.Add(potentialPrime); //increment k to analyze next _k++; } while (_foundPrimes.Count() < retrieve); return _foundPrimes; } } Now there are definitely more things I can do to help make this more efficient, but for the scope of this example, I think this is fine (but still hideous)! Profiling this now yields a happy surprise 27 seconds to generate the 15000 primes with the profiler attached, and only 1.43 seconds without.  One important thing I wanted to call out though was the performance graph now: Notice anything odd?  The %Processor time is above 100%.  This is because there is now more than 1 core in the operation.  A better label for the chart in my mind would have been %Core time, but to each their own. Another odd thing I noticed was that the profiler seemed to be spot on this time in my DumbPrimes class with line details in source, even with comments..  Odd. Profiling Web Applications The last thing that I wanted to cover, that means a lot to me as a web developer, is the great amount of work that Red Gate put into the profiler when profiling web applications.  In my solution, I have a simple MVC4 application setup with 1 page, a single input form, that will output prime values as my WPF app did.  Launching the profiler from Visual Studio as before, nothing is really different in the profiler window, however I did receive a UAC prompt for a Red Gate helper app to integrate with the web server without notification. After requesting 500, 1000, 2000, and 5000 primes, and looking at the profiler session, things are slightly different from before: As you can see, there are 4 spikes of activity in the processor time graph, but there is also something new in the call tree: That’s right – ANTS will actually group method calls by get/post operations, so it is easier to find out what action/page is giving the largest problems…  Pretty cool in my mind! Overview Overall, I think that Red Gate ANTS CLR Profiler has a lot to offer, however I think it also has a long ways to go.  3 Biggest Pros: Ability to easily drill down from time graph, to method calls, to source code Wide variety of counters to choose from when profiling your application Excellent integration/grouping of methods being called from web applications by request – BRILLIANT! 3 Biggest Cons: Issue regarding line details in source view Nit pick – Processor time vs. Core time Nit pick – Lack of full integration with Visual Studio Ratings Ease of Use (7/10) – I marked down here because of the problems with the line level details and the extra work that that entails, and the lack of better integration with Visual Studio. Effectiveness (10/10) – I believe that the profiler does EXACTLY what it purports to do.  Especially with its large variety of performance counters, a definite plus! Features (9/10) – Besides the real time performance monitoring, and the drill downs that I’ve shown here, ANTS also has great integration with ADO.Net, with the ability to show database queries run by your application in the profiler.  This, with the line level details, the web request grouping, reflector integration, and various options to customize your profiling session I think create a great set of features! Customer Service (10/10) – My entire experience with Red Gate personnel has been nothing but good.  their people are friendly, helpful, and happy! UI / UX (8/10) – The interface is very easy to get around, and all of the options are easy to find.  With a little bit of poking around, you’ll be optimizing Hello World in no time flat! Overall (8/10) – Overall, I am happy with the Performance Profiler and its features, as well as with the service I received when working with the Red Gate personnel.  I WOULD recommend you trying the application and seeing if it would fit into your process, BUT, remember there are still some kinks in it to hopefully be worked out. My next post will definitely be shorter (hopefully), but thank you for reading up to here, or skipping ahead!  Please, if you do try the product, drop me a message and let me know what you think!  I would love to hear any opinions you may have on the product. Code Feel free to download the code I used above – download via DropBox

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  • C#/.NET Little Wonders: The ConcurrentDictionary

    - by James Michael Hare
    Once again we consider some of the lesser known classes and keywords of C#.  In this series of posts, we will discuss how the concurrent collections have been developed to help alleviate these multi-threading concerns.  Last week’s post began with a general introduction and discussed the ConcurrentStack<T> and ConcurrentQueue<T>.  Today's post discusses the ConcurrentDictionary<T> (originally I had intended to discuss ConcurrentBag this week as well, but ConcurrentDictionary had enough information to create a very full post on its own!).  Finally next week, we shall close with a discussion of the ConcurrentBag<T> and BlockingCollection<T>. For more of the "Little Wonders" posts, see the index here. Recap As you'll recall from the previous post, the original collections were object-based containers that accomplished synchronization through a Synchronized member.  While these were convenient because you didn't have to worry about writing your own synchronization logic, they were a bit too finely grained and if you needed to perform multiple operations under one lock, the automatic synchronization didn't buy much. With the advent of .NET 2.0, the original collections were succeeded by the generic collections which are fully type-safe, but eschew automatic synchronization.  This cuts both ways in that you have a lot more control as a developer over when and how fine-grained you want to synchronize, but on the other hand if you just want simple synchronization it creates more work. With .NET 4.0, we get the best of both worlds in generic collections.  A new breed of collections was born called the concurrent collections in the System.Collections.Concurrent namespace.  These amazing collections are fine-tuned to have best overall performance for situations requiring concurrent access.  They are not meant to replace the generic collections, but to simply be an alternative to creating your own locking mechanisms. Among those concurrent collections were the ConcurrentStack<T> and ConcurrentQueue<T> which provide classic LIFO and FIFO collections with a concurrent twist.  As we saw, some of the traditional methods that required calls to be made in a certain order (like checking for not IsEmpty before calling Pop()) were replaced in favor of an umbrella operation that combined both under one lock (like TryPop()). Now, let's take a look at the next in our series of concurrent collections!For some excellent information on the performance of the concurrent collections and how they perform compared to a traditional brute-force locking strategy, see this wonderful whitepaper by the Microsoft Parallel Computing Platform team here. ConcurrentDictionary – the fully thread-safe dictionary The ConcurrentDictionary<TKey,TValue> is the thread-safe counterpart to the generic Dictionary<TKey, TValue> collection.  Obviously, both are designed for quick – O(1) – lookups of data based on a key.  If you think of algorithms where you need lightning fast lookups of data and don’t care whether the data is maintained in any particular ordering or not, the unsorted dictionaries are generally the best way to go. Note: as a side note, there are sorted implementations of IDictionary, namely SortedDictionary and SortedList which are stored as an ordered tree and a ordered list respectively.  While these are not as fast as the non-sorted dictionaries – they are O(log2 n) – they are a great combination of both speed and ordering -- and still greatly outperform a linear search. Now, once again keep in mind that if all you need to do is load a collection once and then allow multi-threaded reading you do not need any locking.  Examples of this tend to be situations where you load a lookup or translation table once at program start, then keep it in memory for read-only reference.  In such cases locking is completely non-productive. However, most of the time when we need a concurrent dictionary we are interleaving both reads and updates.  This is where the ConcurrentDictionary really shines!  It achieves its thread-safety with no common lock to improve efficiency.  It actually uses a series of locks to provide concurrent updates, and has lockless reads!  This means that the ConcurrentDictionary gets even more efficient the higher the ratio of reads-to-writes you have. ConcurrentDictionary and Dictionary differences For the most part, the ConcurrentDictionary<TKey,TValue> behaves like it’s Dictionary<TKey,TValue> counterpart with a few differences.  Some notable examples of which are: Add() does not exist in the concurrent dictionary. This means you must use TryAdd(), AddOrUpdate(), or GetOrAdd().  It also means that you can’t use a collection initializer with the concurrent dictionary. TryAdd() replaced Add() to attempt atomic, safe adds. Because Add() only succeeds if the item doesn’t already exist, we need an atomic operation to check if the item exists, and if not add it while still under an atomic lock. TryUpdate() was added to attempt atomic, safe updates. If we want to update an item, we must make sure it exists first and that the original value is what we expected it to be.  If all these are true, we can update the item under one atomic step. TryRemove() was added to attempt atomic, safe removes. To safely attempt to remove a value we need to see if the key exists first, this checks for existence and removes under an atomic lock. AddOrUpdate() was added to attempt an thread-safe “upsert”. There are many times where you want to insert into a dictionary if the key doesn’t exist, or update the value if it does.  This allows you to make a thread-safe add-or-update. GetOrAdd() was added to attempt an thread-safe query/insert. Sometimes, you want to query for whether an item exists in the cache, and if it doesn’t insert a starting value for it.  This allows you to get the value if it exists and insert if not. Count, Keys, Values properties take a snapshot of the dictionary. Accessing these properties may interfere with add and update performance and should be used with caution. ToArray() returns a static snapshot of the dictionary. That is, the dictionary is locked, and then copied to an array as a O(n) operation.  GetEnumerator() is thread-safe and efficient, but allows dirty reads. Because reads require no locking, you can safely iterate over the contents of the dictionary.  The only downside is that, depending on timing, you may get dirty reads. Dirty reads during iteration The last point on GetEnumerator() bears some explanation.  Picture a scenario in which you call GetEnumerator() (or iterate using a foreach, etc.) and then, during that iteration the dictionary gets updated.  This may not sound like a big deal, but it can lead to inconsistent results if used incorrectly.  The problem is that items you already iterated over that are updated a split second after don’t show the update, but items that you iterate over that were updated a split second before do show the update.  Thus you may get a combination of items that are “stale” because you iterated before the update, and “fresh” because they were updated after GetEnumerator() but before the iteration reached them. Let’s illustrate with an example, let’s say you load up a concurrent dictionary like this: 1: // load up a dictionary. 2: var dictionary = new ConcurrentDictionary<string, int>(); 3:  4: dictionary["A"] = 1; 5: dictionary["B"] = 2; 6: dictionary["C"] = 3; 7: dictionary["D"] = 4; 8: dictionary["E"] = 5; 9: dictionary["F"] = 6; Then you have one task (using the wonderful TPL!) to iterate using dirty reads: 1: // attempt iteration in a separate thread 2: var iterationTask = new Task(() => 3: { 4: // iterates using a dirty read 5: foreach (var pair in dictionary) 6: { 7: Console.WriteLine(pair.Key + ":" + pair.Value); 8: } 9: }); And one task to attempt updates in a separate thread (probably): 1: // attempt updates in a separate thread 2: var updateTask = new Task(() => 3: { 4: // iterates, and updates the value by one 5: foreach (var pair in dictionary) 6: { 7: dictionary[pair.Key] = pair.Value + 1; 8: } 9: }); Now that we’ve done this, we can fire up both tasks and wait for them to complete: 1: // start both tasks 2: updateTask.Start(); 3: iterationTask.Start(); 4:  5: // wait for both to complete. 6: Task.WaitAll(updateTask, iterationTask); Now, if I you didn’t know about the dirty reads, you may have expected to see the iteration before the updates (such as A:1, B:2, C:3, D:4, E:5, F:6).  However, because the reads are dirty, we will quite possibly get a combination of some updated, some original.  My own run netted this result: 1: F:6 2: E:6 3: D:5 4: C:4 5: B:3 6: A:2 Note that, of course, iteration is not in order because ConcurrentDictionary, like Dictionary, is unordered.  Also note that both E and F show the value 6.  This is because the output task reached F before the update, but the updates for the rest of the items occurred before their output (probably because console output is very slow, comparatively). If we want to always guarantee that we will get a consistent snapshot to iterate over (that is, at the point we ask for it we see precisely what is in the dictionary and no subsequent updates during iteration), we should iterate over a call to ToArray() instead: 1: // attempt iteration in a separate thread 2: var iterationTask = new Task(() => 3: { 4: // iterates using a dirty read 5: foreach (var pair in dictionary.ToArray()) 6: { 7: Console.WriteLine(pair.Key + ":" + pair.Value); 8: } 9: }); The atomic Try…() methods As you can imagine TryAdd() and TryRemove() have few surprises.  Both first check the existence of the item to determine if it can be added or removed based on whether or not the key currently exists in the dictionary: 1: // try add attempts an add and returns false if it already exists 2: if (dictionary.TryAdd("G", 7)) 3: Console.WriteLine("G did not exist, now inserted with 7"); 4: else 5: Console.WriteLine("G already existed, insert failed."); TryRemove() also has the virtue of returning the value portion of the removed entry matching the given key: 1: // attempt to remove the value, if it exists it is removed and the original is returned 2: int removedValue; 3: if (dictionary.TryRemove("C", out removedValue)) 4: Console.WriteLine("Removed C and its value was " + removedValue); 5: else 6: Console.WriteLine("C did not exist, remove failed."); Now TryUpdate() is an interesting creature.  You might think from it’s name that TryUpdate() first checks for an item’s existence, and then updates if the item exists, otherwise it returns false.  Well, note quite... It turns out when you call TryUpdate() on a concurrent dictionary, you pass it not only the new value you want it to have, but also the value you expected it to have before the update.  If the item exists in the dictionary, and it has the value you expected, it will update it to the new value atomically and return true.  If the item is not in the dictionary or does not have the value you expected, it is not modified and false is returned. 1: // attempt to update the value, if it exists and if it has the expected original value 2: if (dictionary.TryUpdate("G", 42, 7)) 3: Console.WriteLine("G existed and was 7, now it's 42."); 4: else 5: Console.WriteLine("G either didn't exist, or wasn't 7."); The composite Add methods The ConcurrentDictionary also has composite add methods that can be used to perform updates and gets, with an add if the item is not existing at the time of the update or get. The first of these, AddOrUpdate(), allows you to add a new item to the dictionary if it doesn’t exist, or update the existing item if it does.  For example, let’s say you are creating a dictionary of counts of stock ticker symbols you’ve subscribed to from a market data feed: 1: public sealed class SubscriptionManager 2: { 3: private readonly ConcurrentDictionary<string, int> _subscriptions = new ConcurrentDictionary<string, int>(); 4:  5: // adds a new subscription, or increments the count of the existing one. 6: public void AddSubscription(string tickerKey) 7: { 8: // add a new subscription with count of 1, or update existing count by 1 if exists 9: var resultCount = _subscriptions.AddOrUpdate(tickerKey, 1, (symbol, count) => count + 1); 10:  11: // now check the result to see if we just incremented the count, or inserted first count 12: if (resultCount == 1) 13: { 14: // subscribe to symbol... 15: } 16: } 17: } Notice the update value factory Func delegate.  If the key does not exist in the dictionary, the add value is used (in this case 1 representing the first subscription for this symbol), but if the key already exists, it passes the key and current value to the update delegate which computes the new value to be stored in the dictionary.  The return result of this operation is the value used (in our case: 1 if added, existing value + 1 if updated). Likewise, the GetOrAdd() allows you to attempt to retrieve a value from the dictionary, and if the value does not currently exist in the dictionary it will insert a value.  This can be handy in cases where perhaps you wish to cache data, and thus you would query the cache to see if the item exists, and if it doesn’t you would put the item into the cache for the first time: 1: public sealed class PriceCache 2: { 3: private readonly ConcurrentDictionary<string, double> _cache = new ConcurrentDictionary<string, double>(); 4:  5: // adds a new subscription, or increments the count of the existing one. 6: public double QueryPrice(string tickerKey) 7: { 8: // check for the price in the cache, if it doesn't exist it will call the delegate to create value. 9: return _cache.GetOrAdd(tickerKey, symbol => GetCurrentPrice(symbol)); 10: } 11:  12: private double GetCurrentPrice(string tickerKey) 13: { 14: // do code to calculate actual true price. 15: } 16: } There are other variations of these two methods which vary whether a value is provided or a factory delegate, but otherwise they work much the same. Oddities with the composite Add methods The AddOrUpdate() and GetOrAdd() methods are totally thread-safe, on this you may rely, but they are not atomic.  It is important to note that the methods that use delegates execute those delegates outside of the lock.  This was done intentionally so that a user delegate (of which the ConcurrentDictionary has no control of course) does not take too long and lock out other threads. This is not necessarily an issue, per se, but it is something you must consider in your design.  The main thing to consider is that your delegate may get called to generate an item, but that item may not be the one returned!  Consider this scenario: A calls GetOrAdd and sees that the key does not currently exist, so it calls the delegate.  Now thread B also calls GetOrAdd and also sees that the key does not currently exist, and for whatever reason in this race condition it’s delegate completes first and it adds its new value to the dictionary.  Now A is done and goes to get the lock, and now sees that the item now exists.  In this case even though it called the delegate to create the item, it will pitch it because an item arrived between the time it attempted to create one and it attempted to add it. Let’s illustrate, assume this totally contrived example program which has a dictionary of char to int.  And in this dictionary we want to store a char and it’s ordinal (that is, A = 1, B = 2, etc).  So for our value generator, we will simply increment the previous value in a thread-safe way (perhaps using Interlocked): 1: public static class Program 2: { 3: private static int _nextNumber = 0; 4:  5: // the holder of the char to ordinal 6: private static ConcurrentDictionary<char, int> _dictionary 7: = new ConcurrentDictionary<char, int>(); 8:  9: // get the next id value 10: public static int NextId 11: { 12: get { return Interlocked.Increment(ref _nextNumber); } 13: } Then, we add a method that will perform our insert: 1: public static void Inserter() 2: { 3: for (int i = 0; i < 26; i++) 4: { 5: _dictionary.GetOrAdd((char)('A' + i), key => NextId); 6: } 7: } Finally, we run our test by starting two tasks to do this work and get the results… 1: public static void Main() 2: { 3: // 3 tasks attempting to get/insert 4: var tasks = new List<Task> 5: { 6: new Task(Inserter), 7: new Task(Inserter) 8: }; 9:  10: tasks.ForEach(t => t.Start()); 11: Task.WaitAll(tasks.ToArray()); 12:  13: foreach (var pair in _dictionary.OrderBy(p => p.Key)) 14: { 15: Console.WriteLine(pair.Key + ":" + pair.Value); 16: } 17: } If you run this with only one task, you get the expected A:1, B:2, ..., Z:26.  But running this in parallel you will get something a bit more complex.  My run netted these results: 1: A:1 2: B:3 3: C:4 4: D:5 5: E:6 6: F:7 7: G:8 8: H:9 9: I:10 10: J:11 11: K:12 12: L:13 13: M:14 14: N:15 15: O:16 16: P:17 17: Q:18 18: R:19 19: S:20 20: T:21 21: U:22 22: V:23 23: W:24 24: X:25 25: Y:26 26: Z:27 Notice that B is 3?  This is most likely because both threads attempted to call GetOrAdd() at roughly the same time and both saw that B did not exist, thus they both called the generator and one thread got back 2 and the other got back 3.  However, only one of those threads can get the lock at a time for the actual insert, and thus the one that generated the 3 won and the 3 was inserted and the 2 got discarded.  This is why on these methods your factory delegates should be careful not to have any logic that would be unsafe if the value they generate will be pitched in favor of another item generated at roughly the same time.  As such, it is probably a good idea to keep those generators as stateless as possible. Summary The ConcurrentDictionary is a very efficient and thread-safe version of the Dictionary generic collection.  It has all the benefits of type-safety that it’s generic collection counterpart does, and in addition is extremely efficient especially when there are more reads than writes concurrently. Tweet Technorati Tags: C#, .NET, Concurrent Collections, Collections, Little Wonders, Black Rabbit Coder,James Michael Hare

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  • Dynamically loading Assemblies to reduce Runtime Depencies

    - by Rick Strahl
    I've been working on a request to the West Wind Application Configuration library to add JSON support. The config library is a very easy to use code-first approach to configuration: You create a class that holds the configuration data that inherits from a base configuration class, and then assign a persistence provider at runtime that determines where and how the configuration data is store. Currently the library supports .NET Configuration stores (web.config/app.config), XML files, SQL records and string storage.About once a week somebody asks me about JSON support and I've deflected this question for the longest time because frankly I think that JSON as a configuration store doesn't really buy a heck of a lot over XML. Both formats require the user to perform some fixup of the plain configuration data - in XML into XML tags, with JSON using JSON delimiters for properties and property formatting rules. Sure JSON is a little less verbose and maybe a little easier to read if you have hierarchical data, but overall the differences are pretty minor in my opinion. And yet - the requests keep rolling in.Hard Link Issues in a Component LibraryAnother reason I've been hesitant is that I really didn't want to pull in a dependency on an external JSON library - in this case JSON.NET - into the core library. If you're not using JSON.NET elsewhere I don't want a user to have to require a hard dependency on JSON.NET unless they want to use the JSON feature. JSON.NET is also sensitive to versions and doesn't play nice with multiple versions when hard linked. For example, when you have a reference to V4.4 in your project but the host application has a reference to version 4.5 you can run into assembly load problems. NuGet's Update-Package can solve some of this *if* you can recompile, but that's not ideal for a component that's supposed to be just plug and play. This is no criticism of JSON.NET - this really applies to any dependency that might change.  So hard linking the DLL can be problematic for a number reasons, but the primary reason is to not force loading of JSON.NET unless you actually need it when you use the JSON configuration features of the library.Enter Dynamic LoadingSo rather than adding an assembly reference to the project, I decided that it would be better to dynamically load the DLL at runtime and then use dynamic typing to access various classes. This allows me to run without a hard assembly reference and allows more flexibility with version number differences now and in the future.But there are also a couple of downsides:No assembly reference means only dynamic access - no compiler type checking or IntellisenseRequirement for the host application to have reference to JSON.NET or else get runtime errorsThe former is minor, but the latter can be problematic. Runtime errors are always painful, but in this case I'm willing to live with this. If you want to use JSON configuration settings JSON.NET needs to be loaded in the project. If this is a Web project, it'll likely be there already.So there are a few things that are needed to make this work:Dynamically create an instance and optionally attempt to load an Assembly (if not loaded)Load types into dynamic variablesUse Reflection for a few tasks like statics/enumsThe dynamic keyword in C# makes the formerly most difficult Reflection part - method calls and property assignments - fairly painless. But as cool as dynamic is it doesn't handle all aspects of Reflection. Specifically it doesn't deal with object activation, truly dynamic (string based) member activation or accessing of non instance members, so there's still a little bit of work left to do with Reflection.Dynamic Object InstantiationThe first step in getting the process rolling is to instantiate the type you need to work with. This might be a two step process - loading the instance from a string value, since we don't have a hard type reference and potentially having to load the assembly. Although the host project might have a reference to JSON.NET, that instance might have not been loaded yet since it hasn't been accessed yet. In ASP.NET this won't be a problem, since ASP.NET preloads all referenced assemblies on AppDomain startup, but in other executable project, assemblies are just in time loaded only when they are accessed.Instantiating a type is a two step process: Finding the type reference and then activating it. Here's the generic code out of my ReflectionUtils library I use for this:/// <summary> /// Creates an instance of a type based on a string. Assumes that the type's /// </summary> /// <param name="typeName">Common name of the type</param> /// <param name="args">Any constructor parameters</param> /// <returns></returns> public static object CreateInstanceFromString(string typeName, params object[] args) { object instance = null; Type type = null; try { type = GetTypeFromName(typeName); if (type == null) return null; instance = Activator.CreateInstance(type, args); } catch { return null; } return instance; } /// <summary> /// Helper routine that looks up a type name and tries to retrieve the /// full type reference in the actively executing assemblies. /// </summary> /// <param name="typeName"></param> /// <returns></returns> public static Type GetTypeFromName(string typeName) { Type type = null; // Let default name binding find it type = Type.GetType(typeName, false); if (type != null) return type; // look through assembly list var assemblies = AppDomain.CurrentDomain.GetAssemblies(); // try to find manually foreach (Assembly asm in assemblies) { type = asm.GetType(typeName, false); if (type != null) break; } return type; } To use this for loading JSON.NET I have a small factory function that instantiates JSON.NET and sets a bunch of configuration settings on the generated object. The startup code also looks for failure and tries loading up the assembly when it fails since that's the main reason the load would fail. Finally it also caches the loaded instance for reuse (according to James the JSON.NET instance is thread safe and quite a bit faster when cached). Here's what the factory function looks like in JsonSerializationUtils:/// <summary> /// Dynamically creates an instance of JSON.NET /// </summary> /// <param name="throwExceptions">If true throws exceptions otherwise returns null</param> /// <returns>Dynamic JsonSerializer instance</returns> public static dynamic CreateJsonNet(bool throwExceptions = true) { if (JsonNet != null) return JsonNet; lock (SyncLock) { if (JsonNet != null) return JsonNet; // Try to create instance dynamic json = ReflectionUtils.CreateInstanceFromString("Newtonsoft.Json.JsonSerializer"); if (json == null) { try { var ass = AppDomain.CurrentDomain.Load("Newtonsoft.Json"); json = ReflectionUtils.CreateInstanceFromString("Newtonsoft.Json.JsonSerializer"); } catch (Exception ex) { if (throwExceptions) throw; return null; } } if (json == null) return null; json.ReferenceLoopHandling = (dynamic) ReflectionUtils.GetStaticProperty("Newtonsoft.Json.ReferenceLoopHandling", "Ignore"); // Enums as strings in JSON dynamic enumConverter = ReflectionUtils.CreateInstanceFromString("Newtonsoft.Json.Converters.StringEnumConverter"); json.Converters.Add(enumConverter); JsonNet = json; } return JsonNet; }This code's purpose is to return a fully configured JsonSerializer instance. As you can see the code tries to create an instance and when it fails tries to load the assembly, and then re-tries loading.Once the instance is loaded some configuration occurs on it. Specifically I set the ReferenceLoopHandling option to not blow up immediately when circular references are encountered. There are a host of other small config setting that might be useful to set, but the default seem to be good enough in recent versions. Note that I'm setting ReferenceLoopHandling which requires an Enum value to be set. There's no real easy way (short of using the cardinal numeric value) to set a property or pass parameters from static values or enums. This means I still need to use Reflection to make this work. I'm using the same ReflectionUtils class I previously used to handle this for me. The function looks up the type and then uses Type.InvokeMember() to read the static property.Another feature I need is have Enum values serialized as strings rather than numeric values which is the default. To do this I can use the StringEnumConverter to convert enums to strings by adding it to the Converters collection.As you can see there's still a bit of Reflection to be done even in C# 4+ with dynamic, but with a few helpers this process is relatively painless.Doing the actual JSON ConversionFinally I need to actually do my JSON conversions. For the Utility class I need serialization that works for both strings and files so I created four methods that handle these tasks two each for serialization and deserialization for string and file.Here's what the File Serialization looks like:/// <summary> /// Serializes an object instance to a JSON file. /// </summary> /// <param name="value">the value to serialize</param> /// <param name="fileName">Full path to the file to write out with JSON.</param> /// <param name="throwExceptions">Determines whether exceptions are thrown or false is returned</param> /// <param name="formatJsonOutput">if true pretty-formats the JSON with line breaks</param> /// <returns>true or false</returns> public static bool SerializeToFile(object value, string fileName, bool throwExceptions = false, bool formatJsonOutput = false) { dynamic writer = null; FileStream fs = null; try { Type type = value.GetType(); var json = CreateJsonNet(throwExceptions); if (json == null) return false; fs = new FileStream(fileName, FileMode.Create); var sw = new StreamWriter(fs, Encoding.UTF8); writer = Activator.CreateInstance(JsonTextWriterType, sw); if (formatJsonOutput) writer.Formatting = (dynamic)Enum.Parse(FormattingType, "Indented"); writer.QuoteChar = '"'; json.Serialize(writer, value); } catch (Exception ex) { Debug.WriteLine("JsonSerializer Serialize error: " + ex.Message); if (throwExceptions) throw; return false; } finally { if (writer != null) writer.Close(); if (fs != null) fs.Close(); } return true; }You can see more of the dynamic invocation in this code. First I grab the dynamic JsonSerializer instance using the CreateJsonNet() method shown earlier which returns a dynamic. I then create a JsonTextWriter and configure a couple of enum settings on it, and then call Serialize() on the serializer instance with the JsonTextWriter that writes the output to disk. Although this code is dynamic it's still fairly short and readable.For full circle operation here's the DeserializeFromFile() version:/// <summary> /// Deserializes an object from file and returns a reference. /// </summary> /// <param name="fileName">name of the file to serialize to</param> /// <param name="objectType">The Type of the object. Use typeof(yourobject class)</param> /// <param name="binarySerialization">determines whether we use Xml or Binary serialization</param> /// <param name="throwExceptions">determines whether failure will throw rather than return null on failure</param> /// <returns>Instance of the deserialized object or null. Must be cast to your object type</returns> public static object DeserializeFromFile(string fileName, Type objectType, bool throwExceptions = false) { dynamic json = CreateJsonNet(throwExceptions); if (json == null) return null; object result = null; dynamic reader = null; FileStream fs = null; try { fs = new FileStream(fileName, FileMode.Open, FileAccess.Read); var sr = new StreamReader(fs, Encoding.UTF8); reader = Activator.CreateInstance(JsonTextReaderType, sr); result = json.Deserialize(reader, objectType); reader.Close(); } catch (Exception ex) { Debug.WriteLine("JsonNetSerialization Deserialization Error: " + ex.Message); if (throwExceptions) throw; return null; } finally { if (reader != null) reader.Close(); if (fs != null) fs.Close(); } return result; }This code is a little more compact since there are no prettifying options to set. Here JsonTextReader is created dynamically and it receives the output from the Deserialize() operation on the serializer.You can take a look at the full JsonSerializationUtils.cs file on GitHub to see the rest of the operations, but the string operations are very similar - the code is fairly repetitive.These generic serialization utilities isolate the dynamic serialization logic that has to deal with the dynamic nature of JSON.NET, and any code that uses these functions is none the wiser that JSON.NET is dynamically loaded.Using the JsonSerializationUtils WrapperThe final consumer of the SerializationUtils wrapper is an actual ConfigurationProvider, that is responsible for handling reading and writing JSON values to and from files. The provider is simple a small wrapper around the SerializationUtils component and there's very little code to make this work now:The whole provider looks like this:/// <summary> /// Reads and Writes configuration settings in .NET config files and /// sections. Allows reading and writing to default or external files /// and specification of the configuration section that settings are /// applied to. /// </summary> public class JsonFileConfigurationProvider<TAppConfiguration> : ConfigurationProviderBase<TAppConfiguration> where TAppConfiguration: AppConfiguration, new() { /// <summary> /// Optional - the Configuration file where configuration settings are /// stored in. If not specified uses the default Configuration Manager /// and its default store. /// </summary> public string JsonConfigurationFile { get { return _JsonConfigurationFile; } set { _JsonConfigurationFile = value; } } private string _JsonConfigurationFile = string.Empty; public override bool Read(AppConfiguration config) { var newConfig = JsonSerializationUtils.DeserializeFromFile(JsonConfigurationFile, typeof(TAppConfiguration)) as TAppConfiguration; if (newConfig == null) { if(Write(config)) return true; return false; } DecryptFields(newConfig); DataUtils.CopyObjectData(newConfig, config, "Provider,ErrorMessage"); return true; } /// <summary> /// Return /// </summary> /// <typeparam name="TAppConfig"></typeparam> /// <returns></returns> public override TAppConfig Read<TAppConfig>() { var result = JsonSerializationUtils.DeserializeFromFile(JsonConfigurationFile, typeof(TAppConfig)) as TAppConfig; if (result != null) DecryptFields(result); return result; } /// <summary> /// Write configuration to XmlConfigurationFile location /// </summary> /// <param name="config"></param> /// <returns></returns> public override bool Write(AppConfiguration config) { EncryptFields(config); bool result = JsonSerializationUtils.SerializeToFile(config, JsonConfigurationFile,false,true); // Have to decrypt again to make sure the properties are readable afterwards DecryptFields(config); return result; } }This incidentally demonstrates how easy it is to create a new provider for the West Wind Application Configuration component. Simply implementing 3 methods will do in most cases.Note this code doesn't have any dynamic dependencies - all that's abstracted away in the JsonSerializationUtils(). From here on, serializing JSON is just a matter of calling the static methods on the SerializationUtils class.Already, there are several other places in some other tools where I use JSON serialization this is coming in very handy. With a couple of lines of code I was able to add JSON.NET support to an older AJAX library that I use replacing quite a bit of code that was previously in use. And for any other manual JSON operations (in a couple of apps I use JSON Serialization for 'blob' like document storage) this is also going to be handy.Performance?Some of you might be thinking that using dynamic and Reflection can't be good for performance. And you'd be right… In performing some informal testing it looks like the performance of the native code is nearly twice as fast as the dynamic code. Most of the slowness is attributable to type lookups. To test I created a native class that uses an actual reference to JSON.NET and performance was consistently around 85-90% faster with the referenced code. That being said though - I serialized 10,000 objects in 80ms vs. 45ms so this isn't hardly slouchy. For the configuration component speed is not that important because both read and write operations typically happen once on first access and then every once in a while. But for other operations - say a serializer trying to handle AJAX requests on a Web Server one would be well served to create a hard dependency.Dynamic Loading - Worth it?On occasion dynamic loading makes sense. But there's a price to be paid in added code complexity and a performance hit. But for some operations that are not pivotal to a component or application and only used under certain circumstances dynamic loading can be beneficial to avoid having to ship extra files and loading down distributions. These days when you create new projects in Visual Studio with 30 assemblies before you even add your own code, trying to keep file counts under control seems a good idea. It's not the kind of thing you do on a regular basis, but when needed it can be a useful tool. Hopefully some of you find this information useful…© Rick Strahl, West Wind Technologies, 2005-2013Posted in .NET  C#   Tweet !function(d,s,id){var js,fjs=d.getElementsByTagName(s)[0];if(!d.getElementById(id)){js=d.createElement(s);js.id=id;js.src="//platform.twitter.com/widgets.js";fjs.parentNode.insertBefore(js,fjs);}}(document,"script","twitter-wjs"); (function() { var po = document.createElement('script'); po.type = 'text/javascript'; po.async = true; po.src = 'https://apis.google.com/js/plusone.js'; var s = document.getElementsByTagName('script')[0]; s.parentNode.insertBefore(po, s); })();

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  • Dynamically loading Assemblies to reduce Runtime Dependencies

    - by Rick Strahl
    I've been working on a request to the West Wind Application Configuration library to add JSON support. The config library is a very easy to use code-first approach to configuration: You create a class that holds the configuration data that inherits from a base configuration class, and then assign a persistence provider at runtime that determines where and how the configuration data is store. Currently the library supports .NET Configuration stores (web.config/app.config), XML files, SQL records and string storage.About once a week somebody asks me about JSON support and I've deflected this question for the longest time because frankly I think that JSON as a configuration store doesn't really buy a heck of a lot over XML. Both formats require the user to perform some fixup of the plain configuration data - in XML into XML tags, with JSON using JSON delimiters for properties and property formatting rules. Sure JSON is a little less verbose and maybe a little easier to read if you have hierarchical data, but overall the differences are pretty minor in my opinion. And yet - the requests keep rolling in.Hard Link Issues in a Component LibraryAnother reason I've been hesitant is that I really didn't want to pull in a dependency on an external JSON library - in this case JSON.NET - into the core library. If you're not using JSON.NET elsewhere I don't want a user to have to require a hard dependency on JSON.NET unless they want to use the JSON feature. JSON.NET is also sensitive to versions and doesn't play nice with multiple versions when hard linked. For example, when you have a reference to V4.4 in your project but the host application has a reference to version 4.5 you can run into assembly load problems. NuGet's Update-Package can solve some of this *if* you can recompile, but that's not ideal for a component that's supposed to be just plug and play. This is no criticism of JSON.NET - this really applies to any dependency that might change.  So hard linking the DLL can be problematic for a number reasons, but the primary reason is to not force loading of JSON.NET unless you actually need it when you use the JSON configuration features of the library.Enter Dynamic LoadingSo rather than adding an assembly reference to the project, I decided that it would be better to dynamically load the DLL at runtime and then use dynamic typing to access various classes. This allows me to run without a hard assembly reference and allows more flexibility with version number differences now and in the future.But there are also a couple of downsides:No assembly reference means only dynamic access - no compiler type checking or IntellisenseRequirement for the host application to have reference to JSON.NET or else get runtime errorsThe former is minor, but the latter can be problematic. Runtime errors are always painful, but in this case I'm willing to live with this. If you want to use JSON configuration settings JSON.NET needs to be loaded in the project. If this is a Web project, it'll likely be there already.So there are a few things that are needed to make this work:Dynamically create an instance and optionally attempt to load an Assembly (if not loaded)Load types into dynamic variablesUse Reflection for a few tasks like statics/enumsThe dynamic keyword in C# makes the formerly most difficult Reflection part - method calls and property assignments - fairly painless. But as cool as dynamic is it doesn't handle all aspects of Reflection. Specifically it doesn't deal with object activation, truly dynamic (string based) member activation or accessing of non instance members, so there's still a little bit of work left to do with Reflection.Dynamic Object InstantiationThe first step in getting the process rolling is to instantiate the type you need to work with. This might be a two step process - loading the instance from a string value, since we don't have a hard type reference and potentially having to load the assembly. Although the host project might have a reference to JSON.NET, that instance might have not been loaded yet since it hasn't been accessed yet. In ASP.NET this won't be a problem, since ASP.NET preloads all referenced assemblies on AppDomain startup, but in other executable project, assemblies are just in time loaded only when they are accessed.Instantiating a type is a two step process: Finding the type reference and then activating it. Here's the generic code out of my ReflectionUtils library I use for this:/// <summary> /// Creates an instance of a type based on a string. Assumes that the type's /// </summary> /// <param name="typeName">Common name of the type</param> /// <param name="args">Any constructor parameters</param> /// <returns></returns> public static object CreateInstanceFromString(string typeName, params object[] args) { object instance = null; Type type = null; try { type = GetTypeFromName(typeName); if (type == null) return null; instance = Activator.CreateInstance(type, args); } catch { return null; } return instance; } /// <summary> /// Helper routine that looks up a type name and tries to retrieve the /// full type reference in the actively executing assemblies. /// </summary> /// <param name="typeName"></param> /// <returns></returns> public static Type GetTypeFromName(string typeName) { Type type = null; // Let default name binding find it type = Type.GetType(typeName, false); if (type != null) return type; // look through assembly list var assemblies = AppDomain.CurrentDomain.GetAssemblies(); // try to find manually foreach (Assembly asm in assemblies) { type = asm.GetType(typeName, false); if (type != null) break; } return type; } To use this for loading JSON.NET I have a small factory function that instantiates JSON.NET and sets a bunch of configuration settings on the generated object. The startup code also looks for failure and tries loading up the assembly when it fails since that's the main reason the load would fail. Finally it also caches the loaded instance for reuse (according to James the JSON.NET instance is thread safe and quite a bit faster when cached). Here's what the factory function looks like in JsonSerializationUtils:/// <summary> /// Dynamically creates an instance of JSON.NET /// </summary> /// <param name="throwExceptions">If true throws exceptions otherwise returns null</param> /// <returns>Dynamic JsonSerializer instance</returns> public static dynamic CreateJsonNet(bool throwExceptions = true) { if (JsonNet != null) return JsonNet; lock (SyncLock) { if (JsonNet != null) return JsonNet; // Try to create instance dynamic json = ReflectionUtils.CreateInstanceFromString("Newtonsoft.Json.JsonSerializer"); if (json == null) { try { var ass = AppDomain.CurrentDomain.Load("Newtonsoft.Json"); json = ReflectionUtils.CreateInstanceFromString("Newtonsoft.Json.JsonSerializer"); } catch (Exception ex) { if (throwExceptions) throw; return null; } } if (json == null) return null; json.ReferenceLoopHandling = (dynamic) ReflectionUtils.GetStaticProperty("Newtonsoft.Json.ReferenceLoopHandling", "Ignore"); // Enums as strings in JSON dynamic enumConverter = ReflectionUtils.CreateInstanceFromString("Newtonsoft.Json.Converters.StringEnumConverter"); json.Converters.Add(enumConverter); JsonNet = json; } return JsonNet; }This code's purpose is to return a fully configured JsonSerializer instance. As you can see the code tries to create an instance and when it fails tries to load the assembly, and then re-tries loading.Once the instance is loaded some configuration occurs on it. Specifically I set the ReferenceLoopHandling option to not blow up immediately when circular references are encountered. There are a host of other small config setting that might be useful to set, but the default seem to be good enough in recent versions. Note that I'm setting ReferenceLoopHandling which requires an Enum value to be set. There's no real easy way (short of using the cardinal numeric value) to set a property or pass parameters from static values or enums. This means I still need to use Reflection to make this work. I'm using the same ReflectionUtils class I previously used to handle this for me. The function looks up the type and then uses Type.InvokeMember() to read the static property.Another feature I need is have Enum values serialized as strings rather than numeric values which is the default. To do this I can use the StringEnumConverter to convert enums to strings by adding it to the Converters collection.As you can see there's still a bit of Reflection to be done even in C# 4+ with dynamic, but with a few helpers this process is relatively painless.Doing the actual JSON ConversionFinally I need to actually do my JSON conversions. For the Utility class I need serialization that works for both strings and files so I created four methods that handle these tasks two each for serialization and deserialization for string and file.Here's what the File Serialization looks like:/// <summary> /// Serializes an object instance to a JSON file. /// </summary> /// <param name="value">the value to serialize</param> /// <param name="fileName">Full path to the file to write out with JSON.</param> /// <param name="throwExceptions">Determines whether exceptions are thrown or false is returned</param> /// <param name="formatJsonOutput">if true pretty-formats the JSON with line breaks</param> /// <returns>true or false</returns> public static bool SerializeToFile(object value, string fileName, bool throwExceptions = false, bool formatJsonOutput = false) { dynamic writer = null; FileStream fs = null; try { Type type = value.GetType(); var json = CreateJsonNet(throwExceptions); if (json == null) return false; fs = new FileStream(fileName, FileMode.Create); var sw = new StreamWriter(fs, Encoding.UTF8); writer = Activator.CreateInstance(JsonTextWriterType, sw); if (formatJsonOutput) writer.Formatting = (dynamic)Enum.Parse(FormattingType, "Indented"); writer.QuoteChar = '"'; json.Serialize(writer, value); } catch (Exception ex) { Debug.WriteLine("JsonSerializer Serialize error: " + ex.Message); if (throwExceptions) throw; return false; } finally { if (writer != null) writer.Close(); if (fs != null) fs.Close(); } return true; }You can see more of the dynamic invocation in this code. First I grab the dynamic JsonSerializer instance using the CreateJsonNet() method shown earlier which returns a dynamic. I then create a JsonTextWriter and configure a couple of enum settings on it, and then call Serialize() on the serializer instance with the JsonTextWriter that writes the output to disk. Although this code is dynamic it's still fairly short and readable.For full circle operation here's the DeserializeFromFile() version:/// <summary> /// Deserializes an object from file and returns a reference. /// </summary> /// <param name="fileName">name of the file to serialize to</param> /// <param name="objectType">The Type of the object. Use typeof(yourobject class)</param> /// <param name="binarySerialization">determines whether we use Xml or Binary serialization</param> /// <param name="throwExceptions">determines whether failure will throw rather than return null on failure</param> /// <returns>Instance of the deserialized object or null. Must be cast to your object type</returns> public static object DeserializeFromFile(string fileName, Type objectType, bool throwExceptions = false) { dynamic json = CreateJsonNet(throwExceptions); if (json == null) return null; object result = null; dynamic reader = null; FileStream fs = null; try { fs = new FileStream(fileName, FileMode.Open, FileAccess.Read); var sr = new StreamReader(fs, Encoding.UTF8); reader = Activator.CreateInstance(JsonTextReaderType, sr); result = json.Deserialize(reader, objectType); reader.Close(); } catch (Exception ex) { Debug.WriteLine("JsonNetSerialization Deserialization Error: " + ex.Message); if (throwExceptions) throw; return null; } finally { if (reader != null) reader.Close(); if (fs != null) fs.Close(); } return result; }This code is a little more compact since there are no prettifying options to set. Here JsonTextReader is created dynamically and it receives the output from the Deserialize() operation on the serializer.You can take a look at the full JsonSerializationUtils.cs file on GitHub to see the rest of the operations, but the string operations are very similar - the code is fairly repetitive.These generic serialization utilities isolate the dynamic serialization logic that has to deal with the dynamic nature of JSON.NET, and any code that uses these functions is none the wiser that JSON.NET is dynamically loaded.Using the JsonSerializationUtils WrapperThe final consumer of the SerializationUtils wrapper is an actual ConfigurationProvider, that is responsible for handling reading and writing JSON values to and from files. The provider is simple a small wrapper around the SerializationUtils component and there's very little code to make this work now:The whole provider looks like this:/// <summary> /// Reads and Writes configuration settings in .NET config files and /// sections. Allows reading and writing to default or external files /// and specification of the configuration section that settings are /// applied to. /// </summary> public class JsonFileConfigurationProvider<TAppConfiguration> : ConfigurationProviderBase<TAppConfiguration> where TAppConfiguration: AppConfiguration, new() { /// <summary> /// Optional - the Configuration file where configuration settings are /// stored in. If not specified uses the default Configuration Manager /// and its default store. /// </summary> public string JsonConfigurationFile { get { return _JsonConfigurationFile; } set { _JsonConfigurationFile = value; } } private string _JsonConfigurationFile = string.Empty; public override bool Read(AppConfiguration config) { var newConfig = JsonSerializationUtils.DeserializeFromFile(JsonConfigurationFile, typeof(TAppConfiguration)) as TAppConfiguration; if (newConfig == null) { if(Write(config)) return true; return false; } DecryptFields(newConfig); DataUtils.CopyObjectData(newConfig, config, "Provider,ErrorMessage"); return true; } /// <summary> /// Return /// </summary> /// <typeparam name="TAppConfig"></typeparam> /// <returns></returns> public override TAppConfig Read<TAppConfig>() { var result = JsonSerializationUtils.DeserializeFromFile(JsonConfigurationFile, typeof(TAppConfig)) as TAppConfig; if (result != null) DecryptFields(result); return result; } /// <summary> /// Write configuration to XmlConfigurationFile location /// </summary> /// <param name="config"></param> /// <returns></returns> public override bool Write(AppConfiguration config) { EncryptFields(config); bool result = JsonSerializationUtils.SerializeToFile(config, JsonConfigurationFile,false,true); // Have to decrypt again to make sure the properties are readable afterwards DecryptFields(config); return result; } }This incidentally demonstrates how easy it is to create a new provider for the West Wind Application Configuration component. Simply implementing 3 methods will do in most cases.Note this code doesn't have any dynamic dependencies - all that's abstracted away in the JsonSerializationUtils(). From here on, serializing JSON is just a matter of calling the static methods on the SerializationUtils class.Already, there are several other places in some other tools where I use JSON serialization this is coming in very handy. With a couple of lines of code I was able to add JSON.NET support to an older AJAX library that I use replacing quite a bit of code that was previously in use. And for any other manual JSON operations (in a couple of apps I use JSON Serialization for 'blob' like document storage) this is also going to be handy.Performance?Some of you might be thinking that using dynamic and Reflection can't be good for performance. And you'd be right… In performing some informal testing it looks like the performance of the native code is nearly twice as fast as the dynamic code. Most of the slowness is attributable to type lookups. To test I created a native class that uses an actual reference to JSON.NET and performance was consistently around 85-90% faster with the referenced code. This will change though depending on the size of objects serialized - the larger the object the more processing time is spent inside the actual dynamically activated components and the less difference there will be. Dynamic code is always slower, but how much it really affects your application primarily depends on how frequently the dynamic code is called in relation to the non-dynamic code executing. In most situations where dynamic code is used 'to get the process rolling' as I do here the overhead is small enough to not matter.All that being said though - I serialized 10,000 objects in 80ms vs. 45ms so this is hardly slouchy performance. For the configuration component speed is not that important because both read and write operations typically happen once on first access and then every once in a while. But for other operations - say a serializer trying to handle AJAX requests on a Web Server one would be well served to create a hard dependency.Dynamic Loading - Worth it?Dynamic loading is not something you need to worry about but on occasion dynamic loading makes sense. But there's a price to be paid in added code  and a performance hit which depends on how frequently the dynamic code is accessed. But for some operations that are not pivotal to a component or application and are only used under certain circumstances dynamic loading can be beneficial to avoid having to ship extra files adding dependencies and loading down distributions. These days when you create new projects in Visual Studio with 30 assemblies before you even add your own code, trying to keep file counts under control seems like a good idea. It's not the kind of thing you do on a regular basis, but when needed it can be a useful option in your toolset… © Rick Strahl, West Wind Technologies, 2005-2013Posted in .NET  C#   Tweet !function(d,s,id){var js,fjs=d.getElementsByTagName(s)[0];if(!d.getElementById(id)){js=d.createElement(s);js.id=id;js.src="//platform.twitter.com/widgets.js";fjs.parentNode.insertBefore(js,fjs);}}(document,"script","twitter-wjs"); (function() { var po = document.createElement('script'); po.type = 'text/javascript'; po.async = true; po.src = 'https://apis.google.com/js/plusone.js'; var s = document.getElementsByTagName('script')[0]; s.parentNode.insertBefore(po, s); })();

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