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  • chrome.tab.onactivated

    - by Leon Cunningham
    Can someone please show me how to use the chrome.tabs.onActivated. I would like to refresh the tab that is clicked/activated if the url equals: www.example.com. Or if this is the wrong method please tell me what to use. Can someone please show me how to use the chrome.tabs.onActivated. I would like to refresh the tab that is clicked/activated if the url equals: www.example.com. Or if this is the wrong method please tell me what to use.

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  • how to create 2 controllers with same actionresult 2 views but one implementation

    - by amalatsliit
    I got a controller in my mvc application like below. public class BaseController: Controller { protected void LogInfo() { logger.InfoFormat("[SessionID: {0}, RemoteIP: {1}]", Session.SessionID, Request.UserHostAddress); } } public class FirstController : BaseController { public ActionResult Index(string name) { LogInfo(); getQueryString(); if(IsValidRec()) { if(Errors())) { return View("Error"); } var viewname = getViewName(name); return view(viewname); } else return view("NotFound"); } } I need to create another controller(SecondController ) with same ActionResult method that FirstController has but without any implementation. Because I dont wont to repeat same code in 2 ActionResult methods. what is the best way to do that. I tried in following way but I m getting error when I initialize my protected method 'LogInfo()' public class SecondController : BaseController { public ActionResult Index(string name) { var firstcontroller = new FirstController(); return firstcontroller.Index(name); } }

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  • How can I convert my Stream (image data) back into a file

    - by James Hay
    I have a WCF restful service that I'm trying to upload an image to. I have a very basic metod that accepts a stream as it's only parameter and is defined in the contract as: [OperationContract] [WebInvoke(UriTemplate = "ReviewImage", BodyStyle = WebMessageBodyStyle.Bare, Method = "POST")] ReviewImage UploadImage(Stream data); I'm actually consuming this service from flash (which is fairly inconsequntial) which selects a file from the file system and uploads it through the service url. It all works seems to work, adding a breakpoint to the UploadImage method breaks as expected. If I wanted to save this file back to disk, is it just a case of reading this Stream object into a FileStream object that creates the file somewhere? A bit like the this? When i do actually do this the file can not be opened as an image. I'm sure i'm missing a key piece of knowledge here. Does my stream actually contain just the image bytes or does it contain more than that?

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  • DDD: MailService.SendNotificationToUser() or User.Notify()?

    - by cfs
    I seem to stumble on problem after problem giving my entities behavior. I have a system where a user gets a notification when someone comments his article. Right now it is via an e-mail. I'm struggeling how to implement this the DDD way. Option 1 User entity has a Notify method: User.Notify() The method uses C# built in classes to send an e-mail notification via e-mail The problem with having this in the domain is that it is technology spesific, and how a user is notified might change in the future. I feel this belongs to infrastructure, but how then can a user have behavior? Option 2 I create a Service: NotificationService.Notify(User) The Service uses C# built in classes to send an e-mail The pro is that the service could be an Application Service, and as far as I know an application service can use the infrastructure and call things like the System.Net.Mail and repositories for that sake. How would you implement this?

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  • Unable to recieve file contents on server during upload

    - by Khushal
    Hello, I have a JSP page in which I have a file input field from which I browse a csv file and then upload it on server. I am using method = "POST" and ENCTYPE='multipart/form-data' in the form in which this file input field is present. On the servlet side(in the application's servlet) I am making use of apache's commom file upload API-ServletFileUpload API. After getting the FileItem list from the method parseRequest(request) of this API I am unable to get the file name and its content by using the methods getName(), getString() of FileItem API. Needed to know what am I doing wrong or any modifications in my approach that will make my application to work. Any pointers regarding this will be helpful. Thanks in advance!!

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  • Serialize object from within

    - by Maximus
    I have the class testClass which has the method save. This method saves object to a database. But it needs to serialize object before saving. How can I serialize object from within the class to do that? class testClass { private $prop = 777; public function save() { $serializedObject = serialize(self); DB::insert('objects', array('id', 'object')) ->values(array(1, $serializedObject)) ->execute(); } } serialize(self) obviously doesn't work.

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  • Rails Scope for association of 0 size.

    - by MissingHandle
    I'm having trouble figuring out the scope method for all the Foos that have no Bars. That is: class Foo < ActiveRecord::Base has_may :bars end class Bar < ActiveRecord::Base belongs_to :foo end I'd like to write a scope method that returns me all the foos that have no bars. Something like: class Foo < ActiveRecord::Base has_may :bars scope :has_no_bars, includes(:bars).where("COUNT(foo.bars) = 0") end But I don't understand the appropriate syntax. Any help? Happy to use a MetaWhere solution if easier.

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  • Are instance initializers good or bad?

    - by berry120
    I personally quite like instance initializers - I use them to assign default values to things such as collections so when writing constructors I don't have to remember to assign them the same default values each time. It seems quite elegant to me - avoids annoying NPE's popping up and avoids duplicate code. A private method doesn't seem as nice because a) it can't assign values to final fields, b) it could be run elsewhere in code and c) the method still needs to be explicitly called at the start of each constructor. However, the flip side with others I have spoken to is that they're confusing, some people reading the code might not understand what they do or when they're called and thus they could cause more problems than they solve. Are proper use of these initializers something to be encouraged or avoided? Or is it an "each to their own" case?

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  • Java Web Application

    - by Mark R
    I am interested in creating a simple web application that will take in user input, convert it to an XML file and send the file to a database. Coding wise I feel I am okay, it is just the general setup and what implementation to use I am a bit unsure of. At the moment I have a JSP page containing a form, the user fills out the form and on submit a get method is sent to a servlet, in the servlet doGet() method the servlet is instantiating a java object and passing it the user inputted data. The java object then writes that data to an XML file and sends it to the database via REST. All I would be interested to know is if this the standard/optimal way of creating such a web application. Any and all feedback is appreciated. Thanks

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  • List in C# - passing multiple entries as a single object

    - by Karthick
    Hi, I have a method (C#) public void MethodName(List<Order> Order, int ID) I need to pass this to a main page, in which i know to pass integer value to ID, am not able to pass multiple items in a single list. The List order should have two number entries, (ie. Order.number1 and Order.number2) How should i pass a single list as a parameter to this method containing multiple entries of number1 and 2, so that i can loop thro' and find it. Thanks.

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  • Deleting files associated with model - django

    - by alexBrand
    I have the following code in one of my models class PostImage(models.Model): post = models.ForeignKey(Post, related_name="images") # @@@@ figure out a way to have image folders per user... image = models.ImageField(upload_to='images') image_infowindow = models.ImageField(upload_to='images') image_thumb = models.ImageField(upload_to='images') image_web = models.ImageField(upload_to='images') description = models.CharField(max_length=100) order = models.IntegerField(null=True) IMAGE_SIZES = { 'image_infowindow':(70,70), 'image_thumb':(100,100), 'image_web':(640,480), } def delete(self, *args, **kwargs): # delete files.. self.image.delete(save=False) self.image_thumb.delete(save=False) self.image_web.delete(save=False) self.image_infowindow.delete(save=False) super(PostImage, self).delete(*args, **kwargs) I am trying to delete the files when the delete() method is called on PostImage. However, the files are not being removed. As you can see, I am overriding the delete() method, and deleting each ImageField. For some reason however, the files are not being removed.

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  • Uploading video file to server from iPhone

    - by SshUser
    I know how to upload images to a server running PHP, but I am stuck on uploading video. I have used this advice to upload my video file. Posting method is all ok. What I get on the server is a file of 0 bytes. My code is below: - (void)imagePickerController:(UIImagePickerController *)picker didFinishPickingMediaWithInfo:(NSDictionary *)info { NSURL *videoURL = [info objectForKey:UIImagePickerControllerMediaURL]; NSData *videoData = [NSData dataWithContentsOfFile:[videoURL path]]; } This videoData is passed in my POST method. What should I do instead?

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  • Similar Sub-Classes

    - by praks5432
    Lets say I have a class A that is fairly simple like this - public class A{ private int randomField = 0; protected int key; protected double dmg; } Now I want to write a number of sub-classes that inherit the protected fields and only differ based on the initial values that are assigned to those fields - for example, if I wrote two subclasses B and C, the only difference between those two sub-classes would be that the values key and dmg would have different values. They would share a method, set, which would be exactly the same, in that it would affect the same variable. I find when I'm writing these sub-classes I'm repeating myself, as I just change the constructor to set different initial values to key and dmg, and simply copy and paste the set method. Is there a 'good' way to do this?

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  • I can't upload a file with CGIHTTPServer

    - by sdemingo
    Hi all, I'm using the CGIHTTPServer to implement a simple cgi server. I'm trying to upload a file by a form with the post method and the multipart/form-data enctype but I have problems when I recover the value of the fields in the cgi script. When the script catch the form fields, the value of the file is a MiniFieldStorage with two fields only (key and file name), and I can't recover the content of the file. As the API doc shows, this content is in value field of a StorageField but in the MiniFieldStorage this field isn't exits. ¿How can I recover a StorageField with the content of the file instead a MiniStorageField? ¿There are other method to upload a file using CGIHTTPServer? Thanks a lot

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  • Static referencing error

    - by maxflow
    public class HelloWorld { public static void main(String [] args) { char[] b = {'a', 'b', 'a', 'c'}; int p = 4; deleteRepeats(b, p); } public void deleteRepeats(char[] a, int size) { int currentElement; currentElement = 0; do { for (int i = currentElement; i < size-1; i++) { if (a[currentElement] == a[i+1]) a[i+1] = ' '; } currentElement++; } while (currentElement < size-1); } } I get the error: non-static method deleteRepeats(char[],int) cannot be referenced from a static context deleteRepeats(b,p); Can someone tell me what this means? I tried removing "static" from the main method, but I get the error: Exception in thread "main" java.lang.NoSuchMethodError: main. Thanks in advance

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  • Way to kill python thread from inside thread?

    - by user859434
    I have some python code that currently performs expensive computation by performing the computation in parallel through many threads. For a given time period, many threads are created and started on the fly that share the same code which is explicitly stated within the run method of the thread. My question is how do I stop/kill a thread at the end of its run method? (the run is only called once) I need to do this in order to create more threads for the next batch of computation. #Example class someThread(threading.Thread): def __init__(self): #some init code def run(self): #Explicitly Stated Code without constant loops #Something performed to stop/kill this thread

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  • Android camera to take multiple photos

    - by user2975407
    problem.java public class problem extends Activity { ImageView iv; @Override protected void onCreate(Bundle savedInstanceState) { // TODO Auto-generated method stub super.onCreate(savedInstanceState); setContentView(R.layout.problem); iv=(ImageView) findViewById(R.id.imageView1); Button b=(Button) findViewById(R.id.button1); b.setOnClickListener(new OnClickListener() { @Override public void onClick(View v) { Intent intent=new Intent(android.provider.MediaStore.ACTION_IMAGE_CAPTURE); startActivityForResult(intent, 0); } }); } @Override protected void onActivityResult(int requestCode, int resultCode, Intent data) { // TODO Auto-generated method stub super.onActivityResult(requestCode, resultCode, data); Bitmap bm=(Bitmap) data.getExtras().get("data"); iv.setImageBitmap(bm); } } From this code I can only take one photo and it displayed in the screen. **But I want to take more photos nearly 5 photos and display in the screen** Further I want to add these photos to MySQL database.please help me to do that.I am new to android

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  • Trying to serialize and unserialze a Binary search tree to a file

    - by ClearMist
    I am trying to find a way to use these methods to save and restore a binary search tree that contains names and phone numbers in each node. I am just very lost and how to go about doing this. 'public void save(String fileName) { // TODO : implement this method. // save bst to its original shape. } public void restore(String fileName) { // TODO : implement this method. // restore bst from a file, if file exists. // do nothing, otherwise. File fichier = new File(fileName); if (fichier.exists()) { } }'

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  • Deleting the first occurrence of a target in aList [closed]

    - by Bandz Jooz
    /** Replaces each occurrence of oldItem in aList with newItem */ public static void replace(List<Student> aList, Student oldItemStudent newItem) { int index = aList.indexOf(oldItem); while(index != -1){ aList.set(index, newItem); index = aList.indexOf(oldItem); } /** Deletes the first occurrence of target in aList */ public static void delete(List<Student> aList, Student target){ Object o = //stuck here, dont know how to set up boolean stuff } } I figured out how to do the first method by looking up Java documentation, however I can't figure out how to finish my code for the second method even though I looked up the documentation which states: boolean remove(Object o) Removes the first occurrence of the specified element from this list, if it is present.

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  • Module.new with class_eval

    - by dorelal
    This is a large commit. But I want you to concentrate on this change block. http://github.com/rails/rails/commit/d916c62cfc7c59ab6411407a05b946d3dd7535e9#L2L1304 Even without understanding the full context of the code I am not able to think of a scenario where I would use include Modue.new { class_eval <<-RUBY def foo puts 'foo' end RUBY } Then end result is that in the root context (self just before include Moduel.new) a method call foo has been added. If I take out the Module.new code and if I only leave class_eval in that case also I will have a method called foo in self. What am I missing.

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  • Regarding Notify()

    - by user1334074
    I was going through threads and I read that ..The notify() method is used to send a signal to one and only one of the threads that are waiting in that same object's waiting pool. The method notifyAll() works in the same way as notify(), only it sends the signal to all of the threads waiting on the object.... Now my query is that if Lets say I have 5 threads and one main thread , so initially the main thread starts and then five other threads start , Now I want to send notification to third thread only , How could it be possible with the use of notify(), since here I am sending notification to third thread only , please advise.

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  • How to learn programming language (syntax rules, etc.) and remember easily? [closed]

    - by user239522
    I'm new to programming, and I always have a so call difficulty, that is, I always tend to forget the thing (syntax, rules, name, definition or anyting) of a programming language I've learnt. And I personally do feel that the way I learn it is wrong. Here is my method. Everyday I will spend approximately 1 or 2 hours on a programming e-book. I just follow the syllabus and teaching inside the books, of course I have try to code myself, alter the code inside the book, and did the exercises available. But everytime right after I finish a chapter and advanced myself to third or fourth chapter, I will forgot something I learnt in the first chapter. Is it the method I use wrong? Does learning through reading and coding not enough? Do I need to everytime make a small note (mind map for example) of things I've learnt by hand writing? Or do I sometime need to try coding using a pencil and a book, but not a computer?

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  • Scripting with the Sun ZFS Storage 7000 Appliance

    - by Geoff Ongley
    The Sun ZFS Storage 7000 appliance has a user friendly and easy to understand graphical web based interface we call the "BUI" or "Browser User Interface".This interface is very useful for many tasks, but in some cases a script (or workflow) may be more appropriate, such as:Repetitive tasksTasks which work on (or obtain information about) a large number of shares or usersTasks which are triggered by an alert threshold (workflows)Tasks where you want a only very basic input, but a consistent output (workflows)The appliance scripting language is based on ECMAscript 3 (close to javascript). I'm not going to cover ECMAscript 3 in great depth (I'm far from an expert here), but I would like to show you some neat things you can do with the appliance, to get you started based on what I have found from my own playing around.I'm making the assumption you have some sort of programming background, and understand variables, arrays, functions to some extent - but of course if something is not clear, please let me know so I can fix it up or clarify it.Variable Declarations and ArraysVariablesECMAScript is a dynamically and weakly typed language. If you don't know what that means, google is your friend - but at a high level it means we can just declare variables with no specific type and on the fly.For example, I can declare a variable and use it straight away in the middle of my code, for example:projects=list();Which makes projects an array of values that are returned from the list(); function (which is usable in most contexts). With this kind of variable, I can do things like:projects.length (this property on array tells you how many objects are in it, good for for loops etc). Alternatively, I could say:projects=3;and now projects is just a simple number.Should we declare variables like this so loosely? In my opinion, the answer is no - I feel it is a better practice to declare variables you are going to use, before you use them - and given them an initial value. You can do so as follows:var myVariable=0;To demonstrate the ability to just randomly assign and change the type of variables, you can create a simple script at the cli as follows (bold for input):fishy10:> script("." to run)> run("cd /");("." to run)> run ("shares");("." to run)> var projects;("." to run)> projects=list();("." to run)> printf("Number of projects is: %d\n",projects.length);("." to run)> projects=152;("." to run)> printf("Value of the projects variable as an integer is now: %d\n",projects);("." to run)> .Number of projects is: 7Value of the projects variable as an integer is now: 152You can also confirm this behaviour by checking the typeof variable we are dealing with:fishy10:> script("." to run)> run("cd /");("." to run)> run ("shares");("." to run)> var projects;("." to run)> projects=list();("." to run)> printf("var projects is of type %s\n",typeof(projects));("." to run)> projects=152;("." to run)> printf("var projects is of type %s\n",typeof(projects));("." to run)> .var projects is of type objectvar projects is of type numberArraysSo you likely noticed that we have already touched on arrays, as the list(); (in the shares context) stored an array into the 'projects' variable.But what if you want to declare your own array? Easy! This is very similar to Java and other languages, we just instantiate a brand new "Array" object using the keyword new:var myArray = new Array();will create an array called "myArray".A quick example:fishy10:> script("." to run)> testArray = new Array();("." to run)> testArray[0]="This";("." to run)> testArray[1]="is";("." to run)> testArray[2]="just";("." to run)> testArray[3]="a";("." to run)> testArray[4]="test";("." to run)> for (i=0; i < testArray.length; i++)("." to run)> {("." to run)>    printf("Array element %d is %s\n",i,testArray[i]);("." to run)> }("." to run)> .Array element 0 is ThisArray element 1 is isArray element 2 is justArray element 3 is aArray element 4 is testWorking With LoopsFor LoopFor loops are very similar to those you will see in C, java and several other languages. One of the key differences here is, as you were made aware earlier, we can be a bit more sloppy with our variable declarations.The general way you would likely use a for loop is as follows:for (variable; test-case; modifier for variable){}For example, you may wish to declare a variable i as 0; and a MAX_ITERATIONS variable to determine how many times this loop should repeat:var i=0;var MAX_ITERATIONS=10;And then, use this variable to be tested against some case existing (has i reached MAX_ITERATIONS? - if not, increment i using i++);for (i=0; i < MAX_ITERATIONS; i++){ // some work to do}So lets run something like this on the appliance:fishy10:> script("." to run)> var i=0;("." to run)> var MAX_ITERATIONS=10;("." to run)> for (i=0; i < MAX_ITERATIONS; i++)("." to run)> {("." to run)>    printf("The number is %d\n",i);("." to run)> }("." to run)> .The number is 0The number is 1The number is 2The number is 3The number is 4The number is 5The number is 6The number is 7The number is 8The number is 9While LoopWhile loops again are very similar to other languages, we loop "while" a condition is met. For example:fishy10:> script("." to run)> var isTen=false;("." to run)> var counter=0;("." to run)> while(isTen==false)("." to run)> {("." to run)>    if (counter==10) ("." to run)>    { ("." to run)>            isTen=true;   ("." to run)>    } ("." to run)>    printf("Counter is %d\n",counter);("." to run)>    counter++;    ("." to run)> }("." to run)> printf("Loop has ended and Counter is %d\n",counter);("." to run)> .Counter is 0Counter is 1Counter is 2Counter is 3Counter is 4Counter is 5Counter is 6Counter is 7Counter is 8Counter is 9Counter is 10Loop has ended and Counter is 11So what do we notice here? Something has actually gone wrong - counter will technically be 11 once the loop completes... Why is this?Well, if we have a loop like this, where the 'while' condition that will end the loop may be set based on some other condition(s) existing (such as the counter has reached 10) - we must ensure that we  terminate this iteration of the loop when the condition is met - otherwise the rest of the code will be followed which may not be desirable. In other words, like in other languages, we will only ever check the loop condition once we are ready to perform the next iteration, so any other code after we set "isTen" to be true, will still be executed as we can see it was above.We can avoid this by adding a break into our loop once we know we have set the condition - this will stop the rest of the logic being processed in this iteration (and as such, counter will not be incremented). So lets try that again:fishy10:> script("." to run)> var isTen=false;("." to run)> var counter=0;("." to run)> while(isTen==false)("." to run)> {("." to run)>    if (counter==10) ("." to run)>    { ("." to run)>            isTen=true;   ("." to run)>            break;("." to run)>    } ("." to run)>    printf("Counter is %d\n",counter);("." to run)>    counter++;    ("." to run)> }("." to run)> printf("Loop has ended and Counter is %d\n", counter);("." to run)> .Counter is 0Counter is 1Counter is 2Counter is 3Counter is 4Counter is 5Counter is 6Counter is 7Counter is 8Counter is 9Loop has ended and Counter is 10Much better!Methods to Obtain and Manipulate DataGet MethodThe get method allows you to get simple properties from an object, for example a quota from a user. The syntax is fairly simple:var myVariable=get('property');An example of where you may wish to use this, is when you are getting a bunch of information about a user (such as quota information when in a shares context):var users=list();for(k=0; k < users.length; k++){     user=users[k];     run('select ' + user);     var username=get('name');     var usage=get('usage');     var quota=get('quota');...Which you can then use to your advantage - to print or manipulate infomation (you could change a user's information with a set method, based on the information returned from the get method). The set method is explained next.Set MethodThe set method can be used in a simple manner, similar to get. The syntax for set is:set('property','value'); // where value is a string, if it was a number, you don't need quotesFor example, we could set the quota on a share as follows (first observing the initial value):fishy10:shares default/test-geoff> script("." to run)> var currentQuota=get('quota');("." to run)> printf("Current Quota is: %s\n",currentQuota);("." to run)> set('quota','30G');("." to run)> run('commit');("." to run)> currentQuota=get('quota');("." to run)> printf("Current Quota is: %s\n",currentQuota);("." to run)> .Current Quota is: 0Current Quota is: 32212254720This shows us using both the get and set methods as can be used in scripts, of course when only setting an individual share, the above is overkill - it would be much easier to set it manually at the cli using 'set quota=3G' and then 'commit'.List MethodThe list method can be very powerful, especially in more complex scripts which iterate over large amounts of data and manipulate it if so desired. The general way you will use list is as follows:var myVar=list();Which will make "myVar" an array, containing all the objects in the relevant context (this could be a list of users, shares, projects, etc). You can then gather or manipulate data very easily.We could list all the shares and mountpoints in a given project for example:fishy10:shares another-project> script("." to run)> var shares=list();("." to run)> for (i=0; i < shares.length; i++)("." to run)> {("." to run)>    run('select ' + shares[i]);("." to run)>    var mountpoint=get('mountpoint');("." to run)>    printf("Share %s discovered, has mountpoint %s\n",shares[i],mountpoint);("." to run)>    run('done');("." to run)> }("." to run)> .Share and-another discovered, has mountpoint /export/another-project/and-anotherShare another-share discovered, has mountpoint /export/another-project/another-shareShare bob discovered, has mountpoint /export/another-projectShare more-shares-for-all discovered, has mountpoint /export/another-project/more-shares-for-allShare yep discovered, has mountpoint /export/another-project/yepWriting More Complex and Re-Usable CodeFunctionsThe best way to be able to write more complex code is to use functions to split up repeatable or reusable sections of your code. This also makes your more complex code easier to read and understand for other programmers.We write functions as follows:function functionName(variable1,variable2,...,variableN){}For example, we could have a function that takes a project name as input, and lists shares for that project (assuming we're already in the 'project' context - context is important!):function getShares(proj){        run('select ' + proj);        shares=list();        printf("Project: %s\n", proj);        for(j=0; j < shares.length; j++)        {                printf("Discovered share: %s\n",shares[i]);        }        run('done'); // exit selected project}Commenting your CodeLike any other language, a large part of making it readable and understandable is to comment it. You can use the same comment style as in C and Java amongst other languages.In other words, sngle line comments use://at the beginning of the comment.Multi line comments use:/*at the beginning, and:*/ at the end.For example, here we will use both:fishy10:> script("." to run)> // This is a test comment("." to run)> printf("doing some work...\n");("." to run)> /* This is a multi-line("." to run)> comment which I will span across("." to run)> three lines in total */("." to run)> printf("doing some more work...\n");("." to run)> .doing some work...doing some more work...Your comments do not have to be on their own, they can begin (particularly with single line comments this is handy) at the end of a statement, for examplevar projects=list(); // The variable projects is an array containing all projects on the system.Try and Catch StatementsYou may be used to using try and catch statements in other languages, and they can (and should) be utilised in your code to catch expected or unexpected error conditions, that you do NOT wish to stop your code from executing (if you do not catch these errors, your script will exit!):try{  // do some work}catch(err) // Catch any error that could occur{ // do something here under the error condition}For example, you may wish to only execute some code if a context can be reached. If you can't perform certain actions under certain circumstances, that may be perfectly acceptable.For example if you want to test a condition that only makes sense when looking at a SMB/NFS share, but does not make sense when you hit an iscsi or FC LUN, you don't want to stop all processing of other shares you may not have covered yet.For example we may wish to obtain quota information on all shares for all users on a share (but this makes no sense for a LUN):function getShareQuota(shar) // Get quota for each user of this share{        run('select ' + shar);        printf("  SHARE: %s\n", shar);        try        {                run('users');                printf("    %20s        %11s    %11s    %3s\n","Username","Usage(G)","Quota(G)","Quota(%)");                printf("    %20s        %11s    %11s    %4s\n","--------","--------","--------","----");                                users=list();                for(k=0; k < users.length; k++)                {                        user=users[k];                        getUserQuota(user);                }                run('done'); // exit user context        }        catch(err)        {                printf("    SKIPPING %s - This is NOT a NFS or CIFs share, not looking for users\n", shar);        }        run('done'); // done with this share}Running Scripts Remotely over SSHAs you have likely noticed, writing and running scripts for all but the simplest jobs directly on the appliance is not going to be a lot of fun.There's a couple of choices on what you can do here:Create scripts on a remote system and run them over sshCreate scripts, wrapping them in workflow code, so they are stored on the appliance and can be triggered under certain circumstances (like a threshold being reached)We'll cover the first one here, and then cover workflows later on (as these are for the most part just scripts with some wrapper information around them).Creating a SSH Public/Private SSH Key PairLog on to your handy Solaris box (You wouldn't be using any other OS, right? :P) and use ssh-keygen to create a pair of ssh keys. I'm storing this separate to my normal key:[geoff@lightning ~] ssh-keygen -t rsa -b 1024Generating public/private rsa key pair.Enter file in which to save the key (/export/home/geoff/.ssh/id_rsa): /export/home/geoff/.ssh/nas_key_rsaEnter passphrase (empty for no passphrase): Enter same passphrase again: Your identification has been saved in /export/home/geoff/.ssh/nas_key_rsa.Your public key has been saved in /export/home/geoff/.ssh/nas_key_rsa.pub.The key fingerprint is:7f:3d:53:f0:2a:5e:8b:2d:94:2a:55:77:66:5c:9b:14 geoff@lightningInstalling the Public Key on the ApplianceOn your Solaris host, observe the public key:[geoff@lightning ~] cat .ssh/nas_key_rsa.pub ssh-rsa AAAAB3NzaC1yc2EAAAABIwAAAIEAvYfK3RIaAYmMHBOvyhKM41NaSmcgUMC3igPN5gUKJQvSnYmjuWG6CBr1CkF5UcDji7v19jG3qAD5lAMFn+L0CxgRr8TNaAU+hA4/tpAGkjm+dKYSyJgEdMIURweyyfUFXoerweR8AWW5xlovGKEWZTAfvJX9Zqvh8oMQ5UJLUUc= geoff@lightningNow, copy and paste everything after "ssh-rsa" and before "user@hostname" - in this case, geoff@lightning. That is, this bit:AAAAB3NzaC1yc2EAAAABIwAAAIEAvYfK3RIaAYmMHBOvyhKM41NaSmcgUMC3igPN5gUKJQvSnYmjuWG6CBr1CkF5UcDji7v19jG3qAD5lAMFn+L0CxgRr8TNaAU+hA4/tpAGkjm+dKYSyJgEdMIURweyyfUFXoerweR8AWW5xlovGKEWZTAfvJX9Zqvh8oMQ5UJLUUc=Logon to your appliance and get into the preferences -> keys area for this user (root):[geoff@lightning ~] ssh [email protected]: Last login: Mon Dec  6 17:13:28 2010 from 192.168.0.2fishy10:> configuration usersfishy10:configuration users> select rootfishy10:configuration users root> preferences fishy10:configuration users root preferences> keysOR do it all in one hit:fishy10:> configuration users select root preferences keysNow, we create a new public key that will be accepted for this user and set the type to RSA:fishy10:configuration users root preferences keys> createfishy10:configuration users root preferences key (uncommitted)> set type=RSASet the key itself using the string copied previously (between ssh-rsa and user@host), and set the key ensuring you put double quotes around it (eg. set key="<key>"):fishy10:configuration users root preferences key (uncommitted)> set key="AAAAB3NzaC1yc2EAAAABIwAAAIEAvYfK3RIaAYmMHBOvyhKM41NaSmcgUMC3igPN5gUKJQvSnYmjuWG6CBr1CkF5UcDji7v19jG3qAD5lAMFn+L0CxgRr8TNaAU+hA4/tpAGkjm+dKYSyJgEdMIURweyyfUFXoerweR8AWW5xlovGKEWZTAfvJX9Zqvh8oMQ5UJLUUc="Now set the comment for this key (do not use spaces):fishy10:configuration users root preferences key (uncommitted)> set comment="LightningRSAKey" Commit the new key:fishy10:configuration users root preferences key (uncommitted)> commitVerify the key is there:fishy10:configuration users root preferences keys> lsKeys:NAME     MODIFIED              TYPE   COMMENT                                  key-000  2010-10-25 20:56:42   RSA    cycloneRSAKey                           key-001  2010-12-6 17:44:53    RSA    LightningRSAKey                         As you can see, we now have my new key, and a previous key I have created on this appliance.Running your Script over SSH from a Remote SystemHere I have created a basic test script, and saved it as test.ecma3:[geoff@lightning ~] cat test.ecma3 script// This is a test script, By Geoff Ongley 2010.printf("Testing script remotely over ssh\n");.Now, we can run this script remotely with our keyless login:[geoff@lightning ~] ssh -i .ssh/nas_key_rsa root@fishy10 < test.ecma3Pseudo-terminal will not be allocated because stdin is not a terminal.Testing script remotely over sshPutting it Together - An Example Completed Quota Gathering ScriptSo now we have a lot of the basics to creating a script, let us do something useful, like, find out how much every user is using, on every share on the system (you will recognise some of the code from my previous examples): script/************************************** Quick and Dirty Quota Check script ** Written By Geoff Ongley            ** 25 October 2010                    **************************************/function getUserQuota(usr){        run('select ' + usr);        var username=get('name');        var usage=get('usage');        var quota=get('quota');        var usage_g=usage / 1073741824; // convert bytes to gigabytes        var quota_g=quota / 1073741824; // as above        var quota_percent=0        if (quota > 0)        {                quota_percent=(usage / quota)*(100/1);        }        printf("    %20s        %8.2f           %8.2f           %d%%\n",username,usage_g,quota_g,quota_percent);        run('done'); // done with this selected user}function getShareQuota(shar){        //printf("DEBUG: selecting share %s\n", shar);        run('select ' + shar);        printf("  SHARE: %s\n", shar);        try        {                run('users');                printf("    %20s        %11s    %11s    %3s\n","Username","Usage(G)","Quota(G)","Quota(%)");                printf("    %20s        %11s    %11s    %4s\n","--------","--------","--------","--------");                                users=list();                for(k=0; k < users.length; k++)                {                        user=users[k];                        getUserQuota(user);                }                run('done'); // exit user context        }        catch(err)        {                printf("    SKIPPING %s - This is NOT a NFS or CIFs share, not looking for users\n", shar);        }        run('done'); // done with this share}function getShares(proj){        //printf("DEBUG: selecting project %s\n",proj);        run('select ' + proj);        shares=list();        printf("Project: %s\n", proj);        for(j=0; j < shares.length; j++)        {                share=shares[j];                getShareQuota(share);        }        run('done'); // exit selected project}function getProjects(){        run('cd /');        run('shares');        projects=list();                for (i=0; i < projects.length; i++)        {                var project=projects[i];                getShares(project);        }        run('done'); // exit context for all projects}getProjects();.Which can be run as follows, and will print information like this:[geoff@lightning ~/FISHWORKS_SCRIPTS] ssh -i ~/.ssh/nas_key_rsa root@fishy10 < get_quota_utilisation.ecma3Pseudo-terminal will not be allocated because stdin is not a terminal.Project: another-project  SHARE: and-another                Username           Usage(G)       Quota(G)    Quota(%)                --------           --------       --------    --------                  nobody            0.00            0.00        0%                 geoffro            0.05            0.00        0%                   Billy            0.10            0.00        0%                    root            0.00            0.00        0%            testing-user            0.05            0.00        0%  SHARE: another-share                Username           Usage(G)       Quota(G)    Quota(%)                --------           --------       --------    --------                    root            0.00            0.00        0%                  nobody            0.00            0.00        0%                 geoffro            0.05            0.49        9%            testing-user            0.05            0.02        249%                   Billy            0.10            0.29        33%  SHARE: bob                Username           Usage(G)       Quota(G)    Quota(%)                --------           --------       --------    --------                  nobody            0.00            0.00        0%                    root            0.00            0.00        0%  SHARE: more-shares-for-all                Username           Usage(G)       Quota(G)    Quota(%)                --------           --------       --------    --------                   Billy            0.10            0.00        0%            testing-user            0.05            0.00        0%                  nobody            0.00            0.00        0%                    root            0.00            0.00        0%                 geoffro            0.05            0.00        0%  SHARE: yep                Username           Usage(G)       Quota(G)    Quota(%)                --------           --------       --------    --------                    root            0.00            0.00        0%                  nobody            0.00            0.00        0%                   Billy            0.10            0.01        999%            testing-user            0.05            0.49        9%                 geoffro            0.05            0.00        0%Project: default  SHARE: Test-LUN    SKIPPING Test-LUN - This is NOT a NFS or CIFs share, not looking for users  SHARE: test-geoff                Username           Usage(G)       Quota(G)    Quota(%)                --------           --------       --------    --------                 geoffro            0.05            0.00        0%                    root            3.18           10.00        31%                    uucp            0.00            0.00        0%                  nobody            0.59            0.49        119%^CKilled by signal 2.Creating a WorkflowWorkflows are scripts that we store on the appliance, and can have the script execute either on request (even from the BUI), or on an event such as a threshold being met.Workflow BasicsA workflow allows you to create a simple process that can be executed either via the BUI interface interactively, or by an alert being raised (for some threshold being reached, for example).The basics parameters you will have to set for your "workflow object" (notice you're creating a variable, that embodies ECMAScript) are as follows (parameters is optional):name: A name for this workflowdescription: A Description for the workflowparameters: A set of input parameters (useful when you need user input to execute the workflow)execute: The code, the script itself to execute, which will be function (parameters)With parameters, you can specify things like this (slightly modified sample taken from the System Administration Guide):          ...parameters:        variableParam1:         {                             label: 'Name of Share',                             type: 'String'                  },                  variableParam2                  {                             label: 'Share Size',                             type: 'size'                  },execute: ....};  Note the commas separating the sections of name, parameters, execute, and so on. This is important!Also - there is plenty of properties you can set on the parameters for your workflow, these are described in the Sun ZFS Storage System Administration Guide.Creating a Basic Workflow from a Basic ScriptTo make a basic script into a basic workflow, you need to wrap the following around your script to create a 'workflow' object:var workflow = {name: 'Get User Quotas',description: 'Displays Quota Utilisation for each user on each share',execute: function() {// (basic script goes here, minus the "script" at the beginning, and "." at the end)}};However, it appears (at least in my experience to date) that the workflow object may only be happy with one function in the execute parameter - either that or I'm doing something wrong. As far as I can tell, after execute: you should only have a basic one function context like so:execute: function(){}To deal with this, and to give an example similar to our script earlier, I have created another simple quota check, to show the same basic functionality, but in a workflow format:var workflow = {name: 'Get User Quotas',description: 'Displays Quota Utilisation for each user on each share',execute: function () {        run('cd /');        run('shares');        projects=list();                for (i=0; i < projects.length; i++)        {                run('select ' + projects[i]);                shares=list('filesystem');                printf("Project: %s\n", projects[i]);                for(j=0; j < shares.length; j++)                {                        run('select ' +shares[j]);                        try                        {                                run('users');                                printf("  SHARE: %s\n", shares[j]);                                printf("    %20s        %11s    %11s    %3s\n","Username","Usage(G)","Quota(G)","Quota(%)");                                printf("    %20s        %11s    %11s    %4s\n","--------","--------","--------","-------");                                users=list();                                for(k=0; k < users.length; k++)                                {                                        run('select ' + users[k]);                                        username=get('name');                                        usage=get('usage');                                        quota=get('quota');                                        usage_g=usage / 1073741824; // convert bytes to gigabytes                                        quota_g=quota / 1073741824; // as above                                        quota_percent=0                                        if (quota > 0)                                        {                                                quota_percent=(usage / quota)*(100/1);                                        }                                        printf("    %20s        %8.2f   %8.2f   %d%%\n",username,usage_g,quota_g,quota_percent);                                        run('done');                                }                                run('done'); // exit user context                        }                        catch(err)                        {                        //      printf("    %s is a LUN, Not looking for users\n", shares[j]);                        }                        run('done'); // exit selected share context                }                run('done'); // exit project context        }        }};SummaryThe Sun ZFS Storage 7000 Appliance offers lots of different and interesting features to Sun/Oracle customers, including the world renowned Analytics. Hopefully the above will help you to think of new creative things you could be doing by taking advantage of one of the other neat features, the internal scripting engine!Some references are below to help you continue learning more, I'll update this post as I do the same! Enjoy...More information on ECMAScript 3A complete reference to ECMAScript 3 which will help you learn more of the details you may be interested in, can be found here:http://www.ecma-international.org/publications/files/ECMA-ST-ARCH/ECMA-262,%203rd%20edition,%20December%201999.pdfMore Information on Administering the Sun ZFS Storage 7000The Sun ZFS Storage 7000 System Administration guide can be a useful reference point, and can be found here:http://wikis.sun.com/download/attachments/186238602/2010_Q3_2_ADMIN.pdf

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