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  • How to join a Windows Domain and Map Network Drives?

    - by AgainstClint
    I just installed the current build for Ubuntu on a partition for my work computer. I am a novice when it comes to Linux/Ubuntu, which is why I installed it along side windows. I want to learn how to operate and use Ubuntu much more than I do now, so I figured installing it and trying to do day to day functions here would be a "Thrown into the pool with sharks" way to do it, and I like that way. I did however have a few questions: We are on a Domain in Windows, is there any way to join that domain using the Ubuntu partition? We Also have 16 mapped network drives. I don't actually need ALL of them mapped for Ubuntu, but is there a way to Map at least one of them to see/use here in Ubuntu. Outlook Corporate email, how can I sign in/use it while...well, you get the idea. As I said earlier, I am VERY new to Ubuntu, i've only played around with it a bit at home and never at the office. If you could simplify it down for me a bit, that would be great.

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  • Does XPath will return a object other than String

    - by Kalyan
    I have map xml as below. I can retrieve a value using XPath but can I retrieve object instead?. For example I want Map object to be retured if I say /list/* . Is it possible to retrieve as object. <list> <map> <val name="obj_type">USER</val> <val name="ret_name">user</val> <list name="attributes"> <map> <val name="obj_type">USER_ID</val> <val name="ret_name">userID</val> </map> <map> <val name="obj_type"> USER_UsernamePasswordCredential </val> <list name="attributes"> <map> <val name="obj_type">UNP_Username</val> <val name="ret_name">UserName</val> </map> <map> <val name="obj_type">UNP_Password</val> <val name="ret_name">Password</val> </map> </list> </map> </list> </map> </list>

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  • DWR and Spring Security - User is deauthenticated in few seconds

    - by Vojtech
    I am trying to implement user authentication via DWR as follows: public class PublicRemote { @Autowired @Qualifier("authenticationManager") private AuthenticationManager authenticationManager; public Map<String, Object> userLogin(String username, String password, boolean stay) { Map<String, Object> map = new HashMap<>(); UsernamePasswordAuthenticationToken authRequest = new UsernamePasswordAuthenticationToken(username, password); try { Authentication authentication = authenticationManager.authenticate(authRequest); SecurityContextHolder.getContext().setAuthentication(authentication); map.put("success", "true"); } catch (Exception e) { map.put("success", "false"); } return map; } public Map<String, Object> getUserState() { Map<String, Object> map = new HashMap<>(); Authentication authentication = SecurityContextHolder.getContext().getAuthentication(); boolean authenticated = authentication != null && authentication.isAuthenticated(); map.put("authenticated", authenticated); if (authenticated) { map.put("authorities", authentication.getAuthorities()); } return map; } } The authentication works correctly and by calling getUserState() I can see that the user is successfully logged in. The problem is that this state will stay only for few seconds. In probably 5 seconds, the getAuthentication() starts returning null. Is there some problem with session in DWR or is it some misconfiguration of Spring Security?

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  • Loading city/state from SQL Server to Google Maps?

    - by knawlejj
    I'm trying to make a small application that takes a city & state and geocodes that address to a lat/long location. Right now I am utilizing Google Map's API, ColdFusion, and SQL Server. Basically the city and state fields are in a database table and I want to take those locations and get marker put on a Google Map showing where they are. This is my code to do the geocoding, and viewing the source of the page shows that it is correctly looping through my query and placing a location ("Omaha, NE") in the address field, but no marker, or map for that matter, is showing up on the page: function codeAddress() { <cfloop query="GetLocations"> var address = document.getElementById(<cfoutput>#Trim(hometown)#,#Trim(state)#</cfoutput>).value; if (geocoder) { geocoder.geocode( {<cfoutput>#Trim(hometown)#,#Trim(state)#</cfoutput>: address}, function(results, status) { if (status == google.maps.GeocoderStatus.OK) { var marker = new google.maps.Marker({ map: map, position: results[0].geometry.location, title: <cfoutput>#Trim(hometown)#,#Trim(state)#</cfoutput> }); } else { alert("Geocode was not successful for the following reason: " + status); } }); } </cfloop> } And here is the code to initialize the map: var geocoder; var map; function initialize() { geocoder = new google.maps.Geocoder(); var latlng = new google.maps.LatLng(42.4167,-90.4290); var myOptions = { zoom: 5, center: latlng, mapTypeId: google.maps.MapTypeId.ROADMAP } var marker = new google.maps.Marker({ position: latlng, map: map, title: "Test" }); map = new google.maps.Map(document.getElementById("map_canvas"), myOptions); } I do have a map working that uses lat/long that was hard coded into the database table, but I want to be able to just use the city/state and convert that to a lat/long. Any suggestions or direction? Storing the lat/long in the database is also possible, but I don't know how to do that within SQL.

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  • Is it typical for a provider of a web services to also provide client libraries?

    - by HDave
    My company is building a corporate Java web-app and we are leaning towards using GWT-RPC as the client-server protocol for performance reasons. However, in the future, we will need to provide an API for other enterprise systems to access our data as well. For this, we were thinking of a SOAP based web service. In my experience it is common for commercial providers of enterprise web applications to provide client libraries (Java, .NET, C#, etc.). Is this generally the case? I ask because if so, then why bother using SOAP or REST or any standard web services protocol at all? Why not just create a client libraries that communicate via GWT-RPC?

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  • MapRedux - PowerShell and Big Data

    - by Dittenhafer Solutions
    MapRedux – #PowerShell and #Big Data Have you been hearing about “big data”, “map reduce” and other large scale computing terms over the past couple of years and been curious to dig into more detail? Have you read some of the Apache Hadoop online documentation and unfortunately concluded that it wasn't feasible to setup a “test” hadoop environment on your machine? More recently, I have read about some of Microsoft’s work to enable Hadoop on the Azure cloud. Being a "Microsoft"-leaning technologist, I am more inclinded to be successful with experimentation when on the Windows platform. Of course, it is not that I am "religious" about one set of technologies other another, but rather more experienced. Anyway, within the past couple of weeks I have been thinking about PowerShell a bit more as the 2012 PowerShell Scripting Games approach and it occured to me that PowerShell's support for Windows Remote Management (WinRM), and some other inherent features of PowerShell might lend themselves particularly well to a simple implementation of the MapReduce framework. I fired up my PowerShell ISE and started writing just to see where it would take me. Quite simply, the ScriptBlock feature combined with the ability of Invoke-Command to create remote jobs on networked servers provides much of the plumbing of a distributed computing environment. There are some limiting factors of course. Microsoft provided some default settings which prevent PowerShell from taking over a network without administrative approval first. But even with just one adjustment, a given Windows-based machine can become a node in a MapReduce-style distributed computing environment. Ok, so enough introduction. Let's talk about the code. First, any machine that will participate as a remote "node" will need WinRM enabled for remote access, as shown below. This is not exactly practical for hundreds of intended nodes, but for one (or five) machines in a test environment it does just fine. C:> winrm quickconfig WinRM is not set up to receive requests on this machine. The following changes must be made: Set the WinRM service type to auto start. Start the WinRM service. Make these changes [y/n]? y Alternatively, you could take the approach described in the Remotely enable PSRemoting post from the TechNet forum and use PowerShell to create remote scheduled tasks that will call Enable-PSRemoting on each intended node. Invoke-MapRedux Moving on, now that you have one or more remote "nodes" enabled, you can consider the actual Map and Reduce algorithms. Consider the following snippet: $MyMrResults = Invoke-MapRedux -MapReduceItem $Mr -ComputerName $MyNodes -DataSet $dataset -Verbose Invoke-MapRedux takes an instance of a MapReduceItem which references the Map and Reduce scriptblocks, an array of computer names which are the remote nodes, and the initial data set to be processed. As simple as that, you can start working with concepts of big data and the MapReduce paradigm. Now, how did we get there? I have published the initial version of my PsMapRedux PowerShell Module on GitHub. The PsMapRedux module provides the Invoke-MapRedux function described above. Feel free to browse the underlying code and even contribute to the project! In a later post, I plan to show some of the inner workings of the module, but for now let's move on to how the Map and Reduce functions are defined. Map Both the Map and Reduce functions need to follow a prescribed prototype. The prototype for a Map function in the MapRedux module is as follows. A simple scriptblock that takes one PsObject parameter and returns a hashtable. It is important to note that the PsObject $dataset parameter is a MapRedux custom object that has a "Data" property which offers an array of data to be processed by the Map function. $aMap = { Param ( [PsObject] $dataset ) # Indicate the job is running on the remote node. Write-Host ($env:computername + "::Map"); # The hashtable to return $list = @{}; # ... Perform the mapping work and prepare the $list hashtable result with your custom PSObject... # ... The $dataset has a single 'Data' property which contains an array of data rows # which is a subset of the originally submitted data set. # Return the hashtable (Key, PSObject) Write-Output $list; } Reduce Likewise, with the Reduce function a simple prototype must be followed which takes a $key and a result $dataset from the MapRedux's partitioning function (which joins the Map results by key). Again, the $dataset is a MapRedux custom object that has a "Data" property as described in the Map section. $aReduce = { Param ( [object] $key, [PSObject] $dataset ) Write-Host ($env:computername + "::Reduce - Count: " + $dataset.Data.Count) # The hashtable to return $redux = @{}; # Return Write-Output $redux; } All Together Now When everything is put together in a short example script, you implement your Map and Reduce functions, query for some starting data, build the MapReduxItem via New-MapReduxItem and call Invoke-MapRedux to get the process started: # Import the MapRedux and SQL Server providers Import-Module "MapRedux" Import-Module “sqlps” -DisableNameChecking # Query the database for a dataset Set-Location SQLSERVER:\sql\dbserver1\default\databases\myDb $query = "SELECT MyKey, Date, Value1 FROM BigData ORDER BY MyKey"; Write-Host "Query: $query" $dataset = Invoke-SqlCmd -query $query # Build the Map function $MyMap = { Param ( [PsObject] $dataset ) Write-Host ($env:computername + "::Map"); $list = @{}; foreach($row in $dataset.Data) { # Write-Host ("Key: " + $row.MyKey.ToString()); if($list.ContainsKey($row.MyKey) -eq $true) { $s = $list.Item($row.MyKey); $s.Sum += $row.Value1; $s.Count++; } else { $s = New-Object PSObject; $s | Add-Member -Type NoteProperty -Name MyKey -Value $row.MyKey; $s | Add-Member -type NoteProperty -Name Sum -Value $row.Value1; $list.Add($row.MyKey, $s); } } Write-Output $list; } $MyReduce = { Param ( [object] $key, [PSObject] $dataset ) Write-Host ($env:computername + "::Reduce - Count: " + $dataset.Data.Count) $redux = @{}; $count = 0; foreach($s in $dataset.Data) { $sum += $s.Sum; $count += 1; } # Reduce $redux.Add($s.MyKey, $sum / $count); # Return Write-Output $redux; } # Create the item data $Mr = New-MapReduxItem "My Test MapReduce Job" $MyMap $MyReduce # Array of processing nodes... $MyNodes = ("node1", "node2", "node3", "node4", "localhost") # Run the Map Reduce routine... $MyMrResults = Invoke-MapRedux -MapReduceItem $Mr -ComputerName $MyNodes -DataSet $dataset -Verbose # Show the results Set-Location C:\ $MyMrResults | Out-GridView Conclusion I hope you have seen through this article that PowerShell has a significant infrastructure available for distributed computing. While it does take some code to expose a MapReduce-style framework, much of the work is already done and PowerShell could prove to be the the easiest platform to develop and run big data jobs in your corporate data center, potentially in the Azure cloud, or certainly as an academic excerise at home or school. Follow me on Twitter to stay up to date on the continuing progress of my Powershell MapRedux module, and thanks for reading! Daniel

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  • Lookup for data sources in a query

    - by DAXShekhar
    public static str lookupDatasourceOfQuery(Query _query) {     Query                   query = _query;     QueryBuildDataSource    qbds;     int                     dsIterator;     Map                     map = new Map(Types::String, Types::String);     ;     for (dsIterator = 1; dsIterator <= query.dataSourceCount(); dsIterator++)     {         qbds = query.dataSourceNo(dsIterator);         map.insert(qbds.name(), qbds.name());     }     return pickList(map, "Data source", "Data sources"); }

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  • Lookup table display methods

    - by DAXShekhar
    public static client str lookupTableDisplayMethod(str _tableId) {     SysDictTable        dictTable   = new SysDictTable(str2int(_tableId));     ListEnumerator      enum;     Map                 map         = new Map(Types::String, Types::String);     ;     if (dictTable &&         dictTable.rights() > AccessType::NoAccess)     {         enum = dictTable.getListOfDisplayMethods().getEnumerator();         while (enum.moveNext())         {             map.insert(enum.current(), enum.current());         }     }     return pickList(map, "Display method", tableid2pname(_tableId)); }

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  • If I am in the USA, should I not have a hosting provider in another country? [on hold]

    - by johnny
    I saw the various questions on SO about this. I'm not sure they answered me. I'm in the USA. Someone asked me about hosting on a company in South Africa. They are not a big company. This person simply liked the company for whatever reason. I only saw one horror story. Not many reviews really. It is a small outfit from what I can tell. But, the fact of it being in South Africa, does that matter? Do people ever pursue legal action against hosting companies anyway? The users will all be in the States. edit: I'm not sure why this is unclear.

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  • Can I encrypt web.config with a custom protection provider who's assembly is not in the GAC?

    - by James
    I have written a custom protected configuration provider for my web.config. When I try to encrypt my web.config with it I get the following error from aspnet_iisreg aspnet_regiis.exe -pef appSettings . -prov CustomProvider (This is running in my MSBuild) Could not load file or assembly 'MyCustomProviderNamespace' or one of its dependencies. The system cannot find the file specified. After checking with the Fusion log, I confirm it is checking both the GAC, and 'C:/WINNT/Microsoft.NET/Framework/v2.0.50727/' (the location of aspnet_iisreg). But it cannot find the provider. I do not want to move my component into the GAC, I want to leave the custom assembly in my ApplicationBase to copy around to various servers without having to pull/push from the GAC. Here is my provider configuration in the web.config. <configProtectedData> <providers> <add name="CustomProvider" type="MyCustomProviderNamespace.MyCustomProviderClass, MyCustomProviderNamespace" /> </providers> </configProtectedData> I want aspnet_iisreg to check my ApplicationBase Bin folder for this assembly. Has anyone got any ideas?

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  • SSIS 2005 Error while using script component Designer: "Cannot fetch a row from OLE DB provider "BUL

    - by user150541
    I am trying to debug a dts package in SSIS. I have a script component designer where I pass in the input variables to increment a counter. When I try to msgbox the counter value, I get the following error. Error: 0xC0202009 at STAGING1 to STAGING2, STAGING2 Destination [1056]: An OLE DB error has occurred. Error code: 0x80040E14. An OLE DB record is available. Source: "Microsoft SQL Native Client" Hresult: 0x80040E14 Description: "Cannot fetch a row from OLE DB provider "BULK" for linked server "(null)".". An OLE DB record is available. Source: "Microsoft SQL Native Client" Hresult: 0x80040E14 Description: "The OLE DB provider "BULK" for linked server "(null)" reported an error. The provider did not give any information about the error.". An OLE DB record is available. Source: "Microsoft SQL Native Client" Hresult: 0x80040E14 Description: "Reading from DTS buffer timed out.". Below is the part of the code within the script component designer : Imports System Imports System.Data Imports System.Math Imports Microsoft.SqlServer.Dts.Pipeline.Wrapper Imports Microsoft.SqlServer.Dts.Runtime.Wrapper Public Class ScriptMain Inherits UserComponent Dim iCounter As Integer Dim iCurrentVal As Integer Dim sCurrentOracleSeq As String Dim sSeqName As String Dim sSeqAltProcName As String Public Overrides Sub Input0_ProcessInputRow(ByVal Row As Input0Buffer) ' ' Add your code here ' Row.SEQIDNCASE = iCounter + iCurrentVal iCounter += 1 MsgBox(iCounter + iCurrentVal, MsgBoxStyle.Information, "Input0") End Sub Public Overrides Sub PreExecute() sCurrentOracleSeq = Me.Variables.VSEQIDCurVal iCurrentVal = CInt(sCurrentOracleSeq) MsgBox(iCurrentVal, MsgBoxStyle.Information, "No Title") iCounter = 0 sSeqName = Me.Variables.VSEQIDName sSeqAltProcName = Me.Variables.VSEQIDAlterProc End Sub Public Overrides Sub PostExecute() Me.Variables.VSEQIDUpdateSQL = "Begin " & sSeqAltProcName & "('" & sSeqName & "'," & (iCounter + iCurrentVal) & "); End;" End Sub End Class Note that the above part of code works perfectly fine if I comment out the lines that has Msgbox.

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  • Is it possible to use OAuth starting from the service provider website?

    - by Brian Armstrong
    I want to let people create apps that use my API and authenticate them with OAuth. Normally this process starts from the consumer service website (say TwitPic) and they request an access token from the service provider (Twitter). The user is then taken to the service provider website where they have to allow/deny access to to the consumer. I'm wondering if it's possible to initiate this process from the service provider website instead. So in this example you would start on Twitter's site, and maybe there is a section marked "do you want to turn on access for TwitPic?". If you click yes, it passes the access token directly to TwitPic which now has access to your account. Basically, fewer steps. I'm looking at the OAuth docs and it looks like the request token is generated on the consumer side and used later to turn it into an access token. So it's not really designed with what I described above in mind, but I thought there might be a way. http://oauth.net/core/1.0/ (Search for "steps") Thanks!

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  • Can I use encrypt web.config with a custom protection provider who's assembly is not in the GAC?

    - by James
    I have written a custom protected configuration provider for my web.config. When I try to encrypt my web.config with it I get the following error from aspnet_iisreg aspnet_regiis.exe -pef appSettings . -prov CustomProvider (This is running in my MSBuild) Could not load file or assembly 'MyCustomProviderNamespace' or one of its dependencies. The system cannot find the file specified. After checking with the Fusion log, I confirm it is checking both the GAC, and 'C:/WINNT/Microsoft.NET/Framework/v2.0.50727/' (the location of aspnet_iisreg). But it cannot find the provider. I do not want to move my component into the GAC, I want to leave the custom assembly in my ApplicationBase to copy around to various servers without having to pull/push from the GAC. Here is my provider configuration in the web.config. <configProtectedData> <providers> <add name="CustomProvider" type="MyCustomProviderNamespace.MyCustomProviderClass, MyCustomProviderNamespace" /> </providers> </configProtectedData> Has anyone got any ideas?

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  • after assembling jar - No Persistence provider for EntityManager named ....

    - by alabalaa
    im developing a standalone application and it works fine when starting it from my ide(intellij idea), but after creating an uberjar and start the application from it javax.persistence.spi.PersistenceProvider is thrown saying "No Persistence provider for EntityManager named testPU" here is my persistence.xml which is placed under meta-inf directory: <persistence-unit name="testPU" transaction-type="RESOURCE_LOCAL"> <provider>org.hibernate.ejb.HibernatePersistence</provider> <class>test.model.Configuration</class> <properties> <property name="hibernate.connection.username" value="root"/> <property name="hibernate.connection.driver_class" value="com.mysql.jdbc.Driver"/> <property name="hibernate.connection.password" value="root"/> <property name="hibernate.connection.url" value="jdbc:mysql://localhost:3306/test"/> <property name="hibernate.show_sql" value="true"/> <property name="hibernate.dialect" value="org.hibernate.dialect.MySQLInnoDBDialect"/> <property name="hibernate.c3p0.timeout" value="300"/> <property name="hibernate.hbm2ddl.auto" value="update"/> </properties> </persistence-unit> and here is how im creating the entity manager factory: emf = Persistence.createEntityManagerFactory("testPU"); im using maven and tried the assembly plug-in with the default configuration fot it, i dont have much experience with assembling jars and i dont know if im missing something, so if u have any ideas ill be glad to hear them

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  • SimpleMembership, Membership Providers, Universal Providers and the new ASP.NET 4.5 Web Forms and ASP.NET MVC 4 templates

    - by Jon Galloway
    The ASP.NET MVC 4 Internet template adds some new, very useful features which are built on top of SimpleMembership. These changes add some great features, like a much simpler and extensible membership API and support for OAuth. However, the new account management features require SimpleMembership and won't work against existing ASP.NET Membership Providers. I'll start with a summary of top things you need to know, then dig into a lot more detail. Summary: SimpleMembership has been designed as a replacement for traditional the previous ASP.NET Role and Membership provider system SimpleMembership solves common problems people ran into with the Membership provider system and was designed for modern user / membership / storage needs SimpleMembership integrates with the previous membership system, but you can't use a MembershipProvider with SimpleMembership The new ASP.NET MVC 4 Internet application template AccountController requires SimpleMembership and is not compatible with previous MembershipProviders You can continue to use existing ASP.NET Role and Membership providers in ASP.NET 4.5 and ASP.NET MVC 4 - just not with the ASP.NET MVC 4 AccountController The existing ASP.NET Role and Membership provider system remains supported as is part of the ASP.NET core ASP.NET 4.5 Web Forms does not use SimpleMembership; it implements OAuth on top of ASP.NET Membership The ASP.NET Web Site Administration Tool (WSAT) is not compatible with SimpleMembership The following is the result of a few conversations with Erik Porter (PM for ASP.NET MVC) to make sure I had some the overall details straight, combined with a lot of time digging around in ILSpy and Visual Studio's assembly browsing tools. SimpleMembership: The future of membership for ASP.NET The ASP.NET Membership system was introduces with ASP.NET 2.0 back in 2005. It was designed to solve common site membership requirements at the time, which generally involved username / password based registration and profile storage in SQL Server. It was designed with a few extensibility mechanisms - notably a provider system (which allowed you override some specifics like backing storage) and the ability to store additional profile information (although the additional  profile information was packed into a single column which usually required access through the API). While it's sometimes frustrating to work with, it's held up for seven years - probably since it handles the main use case (username / password based membership in a SQL Server database) smoothly and can be adapted to most other needs (again, often frustrating, but it can work). The ASP.NET Web Pages and WebMatrix efforts allowed the team an opportunity to take a new look at a lot of things - e.g. the Razor syntax started with ASP.NET Web Pages, not ASP.NET MVC. The ASP.NET Web Pages team designed SimpleMembership to (wait for it) simplify the task of dealing with membership. As Matthew Osborn said in his post Using SimpleMembership With ASP.NET WebPages: With the introduction of ASP.NET WebPages and the WebMatrix stack our team has really be focusing on making things simpler for the developer. Based on a lot of customer feedback one of the areas that we wanted to improve was the built in security in ASP.NET. So with this release we took that time to create a new built in (and default for ASP.NET WebPages) security provider. I say provider because the new stuff is still built on the existing ASP.NET framework. So what do we call this new hotness that we have created? Well, none other than SimpleMembership. SimpleMembership is an umbrella term for both SimpleMembership and SimpleRoles. Part of simplifying membership involved fixing some common problems with ASP.NET Membership. Problems with ASP.NET Membership ASP.NET Membership was very obviously designed around a set of assumptions: Users and user information would most likely be stored in a full SQL Server database or in Active Directory User and profile information would be optimized around a set of common attributes (UserName, Password, IsApproved, CreationDate, Comment, Role membership...) and other user profile information would be accessed through a profile provider Some problems fall out of these assumptions. Requires Full SQL Server for default cases The default, and most fully featured providers ASP.NET Membership providers (SQL Membership Provider, SQL Role Provider, SQL Profile Provider) require full SQL Server. They depend on stored procedure support, and they rely on SQL Server cache dependencies, they depend on agents for clean up and maintenance. So the main SQL Server based providers don't work well on SQL Server CE, won't work out of the box on SQL Azure, etc. Note: Cory Fowler recently let me know about these Updated ASP.net scripts for use with Microsoft SQL Azure which do support membership, personalization, profile, and roles. But the fact that we need a support page with a set of separate SQL scripts underscores the underlying problem. Aha, you say! Jon's forgetting the Universal Providers, a.k.a. System.Web.Providers! Hold on a bit, we'll get to those... Custom Membership Providers have to work with a SQL-Server-centric API If you want to work with another database or other membership storage system, you need to to inherit from the provider base classes and override a bunch of methods which are tightly focused on storing a MembershipUser in a relational database. It can be done (and you can often find pretty good ones that have already been written), but it's a good amount of work and often leaves you with ugly code that has a bunch of System.NotImplementedException fun since there are a lot of methods that just don't apply. Designed around a specific view of users, roles and profiles The existing providers are focused on traditional membership - a user has a username and a password, some specific roles on the site (e.g. administrator, premium user), and may have some additional "nice to have" optional information that can be accessed via an API in your application. This doesn't fit well with some modern usage patterns: In OAuth and OpenID, the user doesn't have a password Often these kinds of scenarios map better to user claims or rights instead of monolithic user roles For many sites, profile or other non-traditional information is very important and needs to come from somewhere other than an API call that maps to a database blob What would work a lot better here is a system in which you were able to define your users, rights, and other attributes however you wanted and the membership system worked with your model - not the other way around. Requires specific schema, overflow in blob columns I've already mentioned this a few times, but it bears calling out separately - ASP.NET Membership focuses on SQL Server storage, and that storage is based on a very specific database schema. SimpleMembership as a better membership system As you might have guessed, SimpleMembership was designed to address the above problems. Works with your Schema As Matthew Osborn explains in his Using SimpleMembership With ASP.NET WebPages post, SimpleMembership is designed to integrate with your database schema: All SimpleMembership requires is that there are two columns on your users table so that we can hook up to it – an “ID” column and a “username” column. The important part here is that they can be named whatever you want. For instance username doesn't have to be an alias it could be an email column you just have to tell SimpleMembership to treat that as the “username” used to log in. Matthew's example shows using a very simple user table named Users (it could be named anything) with a UserID and Username column, then a bunch of other columns he wanted in his app. Then we point SimpleMemberhip at that table with a one-liner: WebSecurity.InitializeDatabaseFile("SecurityDemo.sdf", "Users", "UserID", "Username", true); No other tables are needed, the table can be named anything we want, and can have pretty much any schema we want as long as we've got an ID and something that we can map to a username. Broaden database support to the whole SQL Server family While SimpleMembership is not database agnostic, it works across the SQL Server family. It continues to support full SQL Server, but it also works with SQL Azure, SQL Server CE, SQL Server Express, and LocalDB. Everything's implemented as SQL calls rather than requiring stored procedures, views, agents, and change notifications. Note that SimpleMembership still requires some flavor of SQL Server - it won't work with MySQL, NoSQL databases, etc. You can take a look at the code in WebMatrix.WebData.dll using a tool like ILSpy if you'd like to see why - there places where SQL Server specific SQL statements are being executed, especially when creating and initializing tables. It seems like you might be able to work with another database if you created the tables separately, but I haven't tried it and it's not supported at this point. Note: I'm thinking it would be possible for SimpleMembership (or something compatible) to run Entity Framework so it would work with any database EF supports. That seems useful to me - thoughts? Note: SimpleMembership has the same database support - anything in the SQL Server family - that Universal Providers brings to the ASP.NET Membership system. Easy to with Entity Framework Code First The problem with with ASP.NET Membership's system for storing additional account information is that it's the gate keeper. That means you're stuck with its schema and accessing profile information through its API. SimpleMembership flips that around by allowing you to use any table as a user store. That means you're in control of the user profile information, and you can access it however you'd like - it's just data. Let's look at a practical based on the AccountModel.cs class in an ASP.NET MVC 4 Internet project. Here I'm adding a Birthday property to the UserProfile class. [Table("UserProfile")] public class UserProfile { [Key] [DatabaseGeneratedAttribute(DatabaseGeneratedOption.Identity)] public int UserId { get; set; } public string UserName { get; set; } public DateTime Birthday { get; set; } } Now if I want to access that information, I can just grab the account by username and read the value. var context = new UsersContext(); var username = User.Identity.Name; var user = context.UserProfiles.SingleOrDefault(u => u.UserName == username); var birthday = user.Birthday; So instead of thinking of SimpleMembership as a big membership API, think of it as something that handles membership based on your user database. In SimpleMembership, everything's keyed off a user row in a table you define rather than a bunch of entries in membership tables that were out of your control. How SimpleMembership integrates with ASP.NET Membership Okay, enough sales pitch (and hopefully background) on why things have changed. How does this affect you? Let's start with a diagram to show the relationship (note: I've simplified by removing a few classes to show the important relationships): So SimpleMembershipProvider is an implementaiton of an ExtendedMembershipProvider, which inherits from MembershipProvider and adds some other account / OAuth related things. Here's what ExtendedMembershipProvider adds to MembershipProvider: The important thing to take away here is that a SimpleMembershipProvider is a MembershipProvider, but a MembershipProvider is not a SimpleMembershipProvider. This distinction is important in practice: you cannot use an existing MembershipProvider (including the Universal Providers found in System.Web.Providers) with an API that requires a SimpleMembershipProvider, including any of the calls in WebMatrix.WebData.WebSecurity or Microsoft.Web.WebPages.OAuth.OAuthWebSecurity. However, that's as far as it goes. Membership Providers still work if you're accessing them through the standard Membership API, and all of the core stuff  - including the AuthorizeAttribute, role enforcement, etc. - will work just fine and without any change. Let's look at how that affects you in terms of the new templates. Membership in the ASP.NET MVC 4 project templates ASP.NET MVC 4 offers six Project Templates: Empty - Really empty, just the assemblies, folder structure and a tiny bit of basic configuration. Basic - Like Empty, but with a bit of UI preconfigured (css / images / bundling). Internet - This has both a Home and Account controller and associated views. The Account Controller supports registration and login via either local accounts and via OAuth / OpenID providers. Intranet - Like the Internet template, but it's preconfigured for Windows Authentication. Mobile - This is preconfigured using jQuery Mobile and is intended for mobile-only sites. Web API - This is preconfigured for a service backend built on ASP.NET Web API. Out of these templates, only one (the Internet template) uses SimpleMembership. ASP.NET MVC 4 Basic template The Basic template has configuration in place to use ASP.NET Membership with the Universal Providers. You can see that configuration in the ASP.NET MVC 4 Basic template's web.config: <profile defaultProvider="DefaultProfileProvider"> <providers> <add name="DefaultProfileProvider" type="System.Web.Providers.DefaultProfileProvider, System.Web.Providers, Version=1.0.0.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35" connectionStringName="DefaultConnection" applicationName="/" /> </providers> </profile> <membership defaultProvider="DefaultMembershipProvider"> <providers> <add name="DefaultMembershipProvider" type="System.Web.Providers.DefaultMembershipProvider, System.Web.Providers, Version=1.0.0.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35" connectionStringName="DefaultConnection" enablePasswordRetrieval="false" enablePasswordReset="true" requiresQuestionAndAnswer="false" requiresUniqueEmail="false" maxInvalidPasswordAttempts="5" minRequiredPasswordLength="6" minRequiredNonalphanumericCharacters="0" passwordAttemptWindow="10" applicationName="/" /> </providers> </membership> <roleManager defaultProvider="DefaultRoleProvider"> <providers> <add name="DefaultRoleProvider" type="System.Web.Providers.DefaultRoleProvider, System.Web.Providers, Version=1.0.0.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35" connectionStringName="DefaultConnection" applicationName="/" /> </providers> </roleManager> <sessionState mode="InProc" customProvider="DefaultSessionProvider"> <providers> <add name="DefaultSessionProvider" type="System.Web.Providers.DefaultSessionStateProvider, System.Web.Providers, Version=1.0.0.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35" connectionStringName="DefaultConnection" /> </providers> </sessionState> This means that it's business as usual for the Basic template as far as ASP.NET Membership works. ASP.NET MVC 4 Internet template The Internet template has a few things set up to bootstrap SimpleMembership: \Models\AccountModels.cs defines a basic user account and includes data annotations to define keys and such \Filters\InitializeSimpleMembershipAttribute.cs creates the membership database using the above model, then calls WebSecurity.InitializeDatabaseConnection which verifies that the underlying tables are in place and marks initialization as complete (for the application's lifetime) \Controllers\AccountController.cs makes heavy use of OAuthWebSecurity (for OAuth account registration / login / management) and WebSecurity. WebSecurity provides account management services for ASP.NET MVC (and Web Pages) WebSecurity can work with any ExtendedMembershipProvider. There's one in the box (SimpleMembershipProvider) but you can write your own. Since a standard MembershipProvider is not an ExtendedMembershipProvider, WebSecurity will throw exceptions if the default membership provider is a MembershipProvider rather than an ExtendedMembershipProvider. Practical example: Create a new ASP.NET MVC 4 application using the Internet application template Install the Microsoft ASP.NET Universal Providers for LocalDB NuGet package Run the application, click on Register, add a username and password, and click submit You'll get the following execption in AccountController.cs::Register: To call this method, the "Membership.Provider" property must be an instance of "ExtendedMembershipProvider". This occurs because the ASP.NET Universal Providers packages include a web.config transform that will update your web.config to add the Universal Provider configuration I showed in the Basic template example above. When WebSecurity tries to use the configured ASP.NET Membership Provider, it checks if it can be cast to an ExtendedMembershipProvider before doing anything else. So, what do you do? Options: If you want to use the new AccountController, you'll either need to use the SimpleMembershipProvider or another valid ExtendedMembershipProvider. This is pretty straightforward. If you want to use an existing ASP.NET Membership Provider in ASP.NET MVC 4, you can't use the new AccountController. You can do a few things: Replace  the AccountController.cs and AccountModels.cs in an ASP.NET MVC 4 Internet project with one from an ASP.NET MVC 3 application (you of course won't have OAuth support). Then, if you want, you can go through and remove other things that were built around SimpleMembership - the OAuth partial view, the NuGet packages (e.g. the DotNetOpenAuthAuth package, etc.) Use an ASP.NET MVC 4 Internet application template and add in a Universal Providers NuGet package. Then copy in the AccountController and AccountModel classes. Create an ASP.NET MVC 3 project and upgrade it to ASP.NET MVC 4 using the steps shown in the ASP.NET MVC 4 release notes. None of these are particularly elegant or simple. Maybe we (or just me?) can do something to make this simpler - perhaps a NuGet package. However, this should be an edge case - hopefully the cases where you'd need to create a new ASP.NET but use legacy ASP.NET Membership Providers should be pretty rare. Please let me (or, preferably the team) know if that's an incorrect assumption. Membership in the ASP.NET 4.5 project template ASP.NET 4.5 Web Forms took a different approach which builds off ASP.NET Membership. Instead of using the WebMatrix security assemblies, Web Forms uses Microsoft.AspNet.Membership.OpenAuth assembly. I'm no expert on this, but from a bit of time in ILSpy and Visual Studio's (very pretty) dependency graphs, this uses a Membership Adapter to save OAuth data into an EF managed database while still running on top of ASP.NET Membership. Note: There may be a way to use this in ASP.NET MVC 4, although it would probably take some plumbing work to hook it up. How does this fit in with Universal Providers (System.Web.Providers)? Just to summarize: Universal Providers are intended for cases where you have an existing ASP.NET Membership Provider and you want to use it with another SQL Server database backend (other than SQL Server). It doesn't require agents to handle expired session cleanup and other background tasks, it piggybacks these tasks on other calls. Universal Providers are not really, strictly speaking, universal - at least to my way of thinking. They only work with databases in the SQL Server family. Universal Providers do not work with Simple Membership. The Universal Providers packages include some web config transforms which you would normally want when you're using them. What about the Web Site Administration Tool? Visual Studio includes tooling to launch the Web Site Administration Tool (WSAT) to configure users and roles in your application. WSAT is built to work with ASP.NET Membership, and is not compatible with Simple Membership. There are two main options there: Use the WebSecurity and OAuthWebSecurity API to manage the users and roles Create a web admin using the above APIs Since SimpleMembership runs on top of your database, you can update your users as you would any other data - via EF or even in direct database edits (in development, of course)

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  • Default Search provider in Internet Explorer 8 Via GP?

    - by Bump
    Does anyone know how to change the default search provider in IE8 Via Group Policy? IE7 seemed to work okay but once I rolled out the IE8 browser update via WSUS, it defaults back to Bing search on all clients which is done Via group policy. I have found some people making custom adm templates to change this behavior on Google but I cannot get a strait forward answer.

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  • How can I change a search provider's URL in IE8?

    - by Traveling Tech Guy
    Now that Google finally allows searching over HTTPS, I switched all my browsers to use https://google.com by default (I documented my effort in my blog). The only browser I couldn't change the URL string in, is IE8. You can either add, remove, or change the priority of a search provider - as far as I've seen. Can anyone suggest a way to change the default search behavior in E8 to go to HTTPS? Thanks.

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  • In GLSL is it possible to offset vertices based on height map colour?

    - by Rob
    I am attempting to generate some terrain based upon a heightmap. I have generated a 32 x 32 grid and a corresponding height map - In my vertex shader I am trying to offset the position of the Y axis based upon the colour of the heightmap, white vertices being higher than black ones. //Vertex Shader Code #version 330 uniform mat4 modelMatrix; uniform mat4 viewMatrix; uniform mat4 projectionMatrix; uniform sampler2D heightmap; layout (location=0) in vec4 vertexPos; layout (location=1) in vec4 vertexColour; layout (location=3) in vec2 vertexTextureCoord; layout (location=4) in float offset; out vec4 fragCol; out vec4 fragPos; out vec2 fragTex; void main() { // Retreive the current pixel's colour vec4 hmColour = texture(heightmap,vertexTextureCoord); // Offset the y position by the value of current texel's colour value ? vec4 offset = vec4(vertexPos.x , vertexPos.y + hmColour.r, vertexPos.z , 1.0); // Final Position gl_Position = projectionMatrix * viewMatrix * modelMatrix * offset; // Data sent to Fragment Shader. fragCol = vertexColour; fragPos = vertexPos; fragTex = vertexTextureCoord; } However the code I have produced only creates a grid with none of the y vertices higher than any others. This is the C++ code that generates the grid and texture co-orientates which I believe to be correct as the texture is mapped to the grid, hence the white blob in the middle. The grid-lines are generated in the fragment shader, sorry for any confusion. I have tried multiplying the r value of hmColour by 1000 unfortunately that had no effect. The only other problem it could be is that the texture coordinate data is incorrect ? for (int z = 0; z < MAP_Z ; z++) { for(int x = 0; x < MAP_X ; x++) { //Generate Vertex Buffer vertexData[iVertex++] = float (x) * MAP_X; vertexData[iVertex++] = 0; vertexData[iVertex++] = -(float) (z) * MAP_Z; //Colour Buffer NOT NEEDED colourData[iColour++] = 255.0f; // R colourData[iColour++] = 1.0f; // G colourData[iColour++] = 0.0f; // B //Texture Buffer textureData[iTexture++] = (float ) x * (1.0f / MAP_X); textureData[iTexture++] = (float ) z * (1.0f / MAP_Z); } } The heightmap texture I am trying to use appears like so (without grid-lines). This is the corresponding fragment shader // Fragment Shader Code #version 330 uniform sampler2D hmTexture; layout (location=0) out vec4 fragColour; in vec2 fragTex; in vec4 pos; void main(void) { vec2 line = fragTex * 32; // Without Gridlines fragColour = texture(hmTexture,fragTex); // With grid lines // + mix(vec4(0.0, 0.0, 1.0, 0.0), vec4(1.0, 1.0, 1.0, 1.0), // smoothstep(0.05,fract(line.y), 0.99) * smoothstep(0.05,fract(line.x),0.99)); }

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  • Can't see why JavaMail doesn't work in a Spring MVC application on Tomcat

    - by Kartoch
    I have wrote a small web application using Spring MVC. It runs on tomcat and use the JavaMail library. At the present time I can't find why the mails are not sent. But I have no pertinent log messages in tomcat log files to find where is the problem. At the present time, my logging is configured in a log4j.properties file in the root of my CLASSPATH: log4j.rootLogger= DEBUG, CONSOLE log4j.appender.CONSOLE=org.apache.log4j.ConsoleAppender log4j.appender.CONSOLE.layout=org.apache.log4j.PatternLayout log4j.appender.CONSOLE.layout.ConversionPattern=%-4r [%t] %-5p %c %x - %m%n How can i see the java mail log message in debug mode ? I think it is related to JDK logging system (as I'm using Sun's JavaMail) but I don't know how to configure it. Edit: Well, one problem solves and another arises. I change my bean definition to include debug support for javamail: mail.debug=true But still no pertinent info in it: DEBUG: JavaMail version 1.4.1ea-SNAPSHOT DEBUG: not loading file: /usr/lib/jvm/java-6-sun-1.6.0.12/jre/lib/javamail.providers DEBUG: java.io.FileNotFoundException: /usr/lib/jvm/java-6-sun-1.6.0.12/jre/lib/javamail.providers (No such file or directory) DEBUG: !anyLoaded DEBUG: not loading resource: /META-INF/javamail.providers DEBUG: successfully loaded resource: /META-INF/javamail.default.providers DEBUG: Tables of loaded providers DEBUG: Providers Listed By Class Name:{com.sun.mail.smtp.SMTPSSLTransport=javax.mail.Provider[TRANSPORT,smtps,com.sun.mail.smtp.SMTPSSLTransport,Sun Microsystems, Inc], com.sun.mail.smtp.SMTPTransport=javax.mail.Provider[TRANSPORT,smtp,com.sun.mail.smtp.SMTPTransport,Sun Microsystems, Inc], com.sun.mail.imap.IMAPSSLStore=javax.mail.Provider[STORE,imaps,com.sun.mail.imap.IMAPSSLStore,Sun Microsystems, Inc], com.sun.mail.pop3.POP3SSLStore=javax.mail.Provider[STORE,pop3s,com.sun.mail.pop3.POP3SSLStore,Sun Microsystems, Inc], com.sun.mail.imap.IMAPStore=javax.mail.Provider[STORE,imap,com.sun.mail.imap.IMAPStore,Sun Microsystems, Inc], com.sun.mail.pop3.POP3Store=javax.mail.Provider[STORE,pop3,com.sun.mail.pop3.POP3Store,Sun Microsystems, Inc]} DEBUG: Providers Listed By Protocol: {imaps=javax.mail.Provider[STORE,imaps,com.sun.mail.imap.IMAPSSLStore,Sun Microsystems, Inc], imap=javax.mail.Provider[STORE,imap,com.sun.mail.imap.IMAPStore,Sun Microsystems, Inc], smtps=javax.mail.Provider[TRANSPORT,smtps,com.sun.mail.smtp.SMTPSSLTransport,Sun Microsystems, Inc], pop3=javax.mail.Provider[STORE,pop3,com.sun.mail.pop3.POP3Store,Sun Microsystems, Inc], pop3s=javax.mail.Provider[STORE,pop3s,com.sun.mail.pop3.POP3SSLStore,Sun Microsystems, Inc], smtp=javax.mail.Provider[TRANSPORT,smtp,com.sun.mail.smtp.SMTPTransport,Sun Microsystems, Inc]} DEBUG: successfully loaded resource: /META-INF/javamail.default.address.map DEBUG: !anyLoaded DEBUG: not loading resource: /META-INF/javamail.address.map DEBUG: not loading file: /usr/lib/jvm/java-6-sun-1.6.0.12/jre/lib/javamail.address.map DEBUG: java.io.FileNotFoundException: /usr/lib/jvm/java-6-sun-1.6.0.12/jre/lib/javamail.address.map (No such file or directory)

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  • Google maps API - info window height and panning

    - by Tim Fountain
    I'm using the Google maps API (v2) to display a country overlay over a world map. The data comes from a KML file, which contains coords for the polygons along with a HTML description for each country. This description is displayed in the 'info window' speech bubble when that country is clicked on. I had some trouble initially as the info windows were not expanding to the size of the HTML content they contained, so the longer ones would spill over the edges (this seems to be a common problem). I was able to work around this by resetting the info window to a specific height as follows: GEvent.addListener(map, "infowindowopen", function(iw) { iw = map.getInfoWindow(); iw.reset(iw.getPoint(), iw.getTabs(), new GSize(300, 295), null, null); }); Not ideal, but it works. However now, when the info windows are opened the top part of them is sometimes obscured by the edges of the map, as the map does not pan to a position where all of the content can be viewed. So my questions: Is there any way to get the info windows to automatically use a height appropriate to their content, to avoid having to fix to a set pixel height? If fixing the height is the only option, is there any way to get the map to pan to a more appropriate position when the info windows open? I know that the map class has a panTo() method, but I can't see a way to calculate what the correct coords would be. Here's my full init code: google.load("maps", "2.x"); // Call this function when the page has been loaded function initialize() { var map = new google.maps.Map2(document.getElementById("map"), {backgroundColor:'#99b3cc'}); map.addControl(new GSmallZoomControl()); map.setCenter(new google.maps.LatLng(29.01377076013671, -2.7866649627685547), 2); gae_countries = new GGeoXml("http://example.com/countries.kmz"); map.addOverlay(gae_countries); GEvent.addListener(map, "infowindowopen", function(iw) { iw = map.getInfoWindow(); iw.reset(iw.getPoint(), iw.getTabs(), new GSize(300, 295), null, null); }); } google.setOnLoadCallback(initialize);

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  • Why does std::map operator[] create an object if the key doesn't exist?

    - by n1ck
    Hi, I'm pretty sure I already saw this question somewhere (comp.lang.c++? Google doesn't seem to find it there either) but a quick search here doesn't seem to find it so here it is: Why does the std::map operator[] create an object if the key doesn't exist? I don't know but for me this seems counter-intuitive if you compare to most other operator[] (like std::vector) where if you use it you must be sure that the index exists. I'm wondering what's the rationale for implementing this behavior in std::map. Like I said wouldn't it be more intuitive to act more like an index in a vector and crash (well undefined behavior I guess) when accessed with an invalid key? Refining my question after seeing the answers: Ok so far I got a lot of answers saying basically it's cheap so why not or things similar. I totally agree with that but why not use a dedicated function for that (I think one of the comment said that in java there is no operator[] and the function is called put)? My point is why doesn't map operator[] work like a vector? If I use operator[] on an out of range index on a vector I wouldn't like it to insert an element even if it was cheap because that probably mean an error in my code. My point is why isn't it the same thing with map. I mean, for me, using operator[] on a map would mean: i know this key already exist (for whatever reason, i just inserted it, I have redundancy somewhere, whatever). I think it would be more intuitive that way. That said what are the advantage of doing the current behavior with operator[] (and only for that, I agree that a function with the current behavior should be there, just not operator[])? Maybe it give clearer code that way? I don't know. Another answer was that it already existed that way so why not keep it but then, probably when they (the ones before stl) choose to implement it that way they found it provided an advantage or something? So my question is basically: why choose to implement it that way, meaning a somewhat lack of consistency with other operator[]. What benefit do it give? Thanks

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  • StreamInsight 2.1, meet LINQ

    - by Roman Schindlauer
    Someone recently called LINQ “magic” in my hearing. I leapt to LINQ’s defense immediately. Turns out some people don’t realize “magic” is can be a pejorative term. I thought LINQ needed demystification. Here’s your best demystification resource: http://blogs.msdn.com/b/mattwar/archive/2008/11/18/linq-links.aspx. I won’t repeat much of what Matt Warren says in his excellent series, but will talk about some core ideas and how they affect the 2.1 release of StreamInsight. Let’s tell the story of a LINQ query. Compile time It begins with some code: IQueryable<Product> products = ...; var query = from p in products             where p.Name == "Widget"             select p.ProductID; foreach (int id in query) {     ... When the code is compiled, the C# compiler (among other things) de-sugars the query expression (see C# spec section 7.16): ... var query = products.Where(p => p.Name == "Widget").Select(p => p.ProductID); ... Overload resolution subsequently binds the Queryable.Where<Product> and Queryable.Select<Product, int> extension methods (see C# spec sections 7.5 and 7.6.5). After overload resolution, the compiler knows something interesting about the anonymous functions (lambda syntax) in the de-sugared code: they must be converted to expression trees, i.e.,“an object structure that represents the structure of the anonymous function itself” (see C# spec section 6.5). The conversion is equivalent to the following rewrite: ... var prm1 = Expression.Parameter(typeof(Product), "p"); var prm2 = Expression.Parameter(typeof(Product), "p"); var query = Queryable.Select<Product, int>(     Queryable.Where<Product>(         products,         Expression.Lambda<Func<Product, bool>>(Expression.Property(prm1, "Name"), prm1)),         Expression.Lambda<Func<Product, int>>(Expression.Property(prm2, "ProductID"), prm2)); ... If the “products” expression had type IEnumerable<Product>, the compiler would have chosen the Enumerable.Where and Enumerable.Select extension methods instead, in which case the anonymous functions would have been converted to delegates. At this point, we’ve reduced the LINQ query to familiar code that will compile in C# 2.0. (Note that I’m using C# snippets to illustrate transformations that occur in the compiler, not to suggest a viable compiler design!) Runtime When the above program is executed, the Queryable.Where method is invoked. It takes two arguments. The first is an IQueryable<> instance that exposes an Expression property and a Provider property. The second is an expression tree. The Queryable.Where method implementation looks something like this: public static IQueryable<T> Where<T>(this IQueryable<T> source, Expression<Func<T, bool>> predicate) {     return source.Provider.CreateQuery<T>(     Expression.Call(this method, source.Expression, Expression.Quote(predicate))); } Notice that the method is really just composing a new expression tree that calls itself with arguments derived from the source and predicate arguments. Also notice that the query object returned from the method is associated with the same provider as the source query. By invoking operator methods, we’re constructing an expression tree that describes a query. Interestingly, the compiler and operator methods are colluding to construct a query expression tree. The important takeaway is that expression trees are built in one of two ways: (1) by the compiler when it sees an anonymous function that needs to be converted to an expression tree, and; (2) by a query operator method that constructs a new queryable object with an expression tree rooted in a call to the operator method (self-referential). Next we hit the foreach block. At this point, the power of LINQ queries becomes apparent. The provider is able to determine how the query expression tree is evaluated! The code that began our story was intentionally vague about the definition of the “products” collection. Maybe it is a queryable in-memory collection of products: var products = new[]     { new Product { Name = "Widget", ProductID = 1 } }.AsQueryable(); The in-memory LINQ provider works by rewriting Queryable method calls to Enumerable method calls in the query expression tree. It then compiles the expression tree and evaluates it. It should be mentioned that the provider does not blindly rewrite all Queryable calls. It only rewrites a call when its arguments have been rewritten in a way that introduces a type mismatch, e.g. the first argument to Queryable.Where<Product> being rewritten as an expression of type IEnumerable<Product> from IQueryable<Product>. The type mismatch is triggered initially by a “leaf” expression like the one associated with the AsQueryable query: when the provider recognizes one of its own leaf expressions, it replaces the expression with the original IEnumerable<> constant expression. I like to think of this rewrite process as “type irritation” because the rewritten leaf expression is like a foreign body that triggers an immune response (further rewrites) in the tree. The technique ensures that only those portions of the expression tree constructed by a particular provider are rewritten by that provider: no type irritation, no rewrite. Let’s consider the behavior of an alternative LINQ provider. If “products” is a collection created by a LINQ to SQL provider: var products = new NorthwindDataContext().Products; the provider rewrites the expression tree as a SQL query that is then evaluated by your favorite RDBMS. The predicate may ultimately be evaluated using an index! In this example, the expression associated with the Products property is the “leaf” expression. StreamInsight 2.1 For the in-memory LINQ to Objects provider, a leaf is an in-memory collection. For LINQ to SQL, a leaf is a table or view. When defining a “process” in StreamInsight 2.1, what is a leaf? To StreamInsight a leaf is logic: an adapter, a sequence, or even a query targeting an entirely different LINQ provider! How do we represent the logic? Remember that a standing query may outlive the client that provisioned it. A reference to a sequence object in the client application is therefore not terribly useful. But if we instead represent the code constructing the sequence as an expression, we can host the sequence in the server: using (var server = Server.Connect(...)) {     var app = server.Applications["my application"];     var source = app.DefineObservable(() => Observable.Range(0, 10, Scheduler.NewThread));     var query = from i in source where i % 2 == 0 select i; } Example 1: defining a source and composing a query Let’s look in more detail at what’s happening in example 1. We first connect to the remote server and retrieve an existing app. Next, we define a simple Reactive sequence using the Observable.Range method. Notice that the call to the Range method is in the body of an anonymous function. This is important because it means the source sequence definition is in the form of an expression, rather than simply an opaque reference to an IObservable<int> object. The variation in Example 2 fails. Although it looks similar, the sequence is now a reference to an in-memory observable collection: var local = Observable.Range(0, 10, Scheduler.NewThread); var source = app.DefineObservable(() => local); // can’t serialize ‘local’! Example 2: error referencing unserializable local object The Define* methods support definitions of operator tree leaves that target the StreamInsight server. These methods all have the same basic structure. The definition argument is a lambda expression taking between 0 and 16 arguments and returning a source or sink. The method returns a proxy for the source or sink that can then be used for the usual style of LINQ query composition. The “define” methods exploit the compile-time C# feature that converts anonymous functions into translatable expression trees! Query composition exploits the runtime pattern that allows expression trees to be constructed by operators taking queryable and expression (Expression<>) arguments. The practical upshot: once you’ve Defined a source, you can compose LINQ queries in the familiar way using query expressions and operator combinators. Notably, queries can be composed using pull-sequences (LINQ to Objects IQueryable<> inputs), push sequences (Reactive IQbservable<> inputs), and temporal sequences (StreamInsight IQStreamable<> inputs). You can even construct processes that span these three domains using “bridge” method overloads (ToEnumerable, ToObservable and To*Streamable). Finally, the targeted rewrite via type irritation pattern is used to ensure that StreamInsight computations can leverage other LINQ providers as well. Consider the following example (this example depends on Interactive Extensions): var source = app.DefineEnumerable((int id) =>     EnumerableEx.Using(() =>         new NorthwindDataContext(), context =>             from p in context.Products             where p.ProductID == id             select p.ProductName)); Within the definition, StreamInsight has no reason to suspect that it ‘owns’ the Queryable.Where and Queryable.Select calls, and it can therefore defer to LINQ to SQL! Let’s use this source in the context of a StreamInsight process: var sink = app.DefineObserver(() => Observer.Create<string>(Console.WriteLine)); var query = from name in source(1).ToObservable()             where name == "Widget"             select name; using (query.Bind(sink).Run("process")) {     ... } When we run the binding, the source portion which filters on product ID and projects the product name is evaluated by SQL Server. Outside of the definition, responsibility for evaluation shifts to the StreamInsight server where we create a bridge to the Reactive Framework (using ToObservable) and evaluate an additional predicate. It’s incredibly easy to define computations that span multiple domains using these new features in StreamInsight 2.1! Regards, The StreamInsight Team

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