Just code - Tamir Khason : WCF, Web

New year – new blog or how to migrate Community Server to any other engine, supports XML-RPC

Tamir Khason — Fri, 02 Jan 2009 02:33:04 GMT

Please update your bookmarks, because the new url of this blog is http://khason.net/ (you have not update RSS feeds, it will be done automatically). Why I did it? Why I decided to go to “stand-alone”… Well. there are some reasons. Generally, I do not want to explain all those here, but trust me, there are some. The main reason is, that there is no responsible person in charge for this blog platform in Microsoft Israel. This why, if your blog is popular and you have a respect to your blog visitors, you cannot host it here… Take a look into new comments notifications in my inbox. Would you answer your readers with such “small amount” of SPAM and capcha, that cannot be fixed already for three years in this platform? This how my inbox looks like for last three years. So now, you should not ask me, why I not answered your email or comments. Aren’t you? :)

Currently, all comments in this blog are disabled, so if you want to comment, please use new url of posts (this will appear shortly in the beginning of each post). Also, this post will not be syndicated in RSS.

So, this post is the last. I loved this platform, and loved people started it. But, unfortunately, it seemed, that bloggers community is not important enough for new platform managers.

Also, If you want to learn how to use C# and XML-RCP to migrate from CS2007, used in this platform, visit my new home :)

Have a great year and, as always, be good people. This post marked with all possible tags automatically. Sorry.

.NET 3.5 SP1 is RTM and available for download

Tamir Khason — Mon, 11 Aug 2008 15:12:48 GMT

[This blog was migrated. You will not be able to comment here.
The new URL of this post is http://khason.net/blog/net-35-sp1-is-rtm-and-available-for-download/]

For all those who asked, .NET 3.5 SP1 is final and available for download. What’s inside?

ASP.NET Dynamic data
Core improvements for CLR
A lot of performance improvements in WPF
ClickOnce enhancements
ADO.NET with Data Services and Entity Framework
LINQ2SQL and Data Provider for SQL Server 2008, that was released last week
WCF with easier DataContract serialization

Download it with Web Installation or as Full Package

For more information, please see Read Me and KB about .NET 3.5 SP1 RTM. If you faced with any issue, please provide us with feedback via MS Connect

How to consume WCF or Webservice from Vista Sidebar gadget by using Silverlight?

Tamir Khason — Tue, 24 Jun 2008 01:37:10 GMT

[This blog was migrated. You will not be able to comment here.
The new URL of this post is http://khason.net/blog/how-to-consume-wcf-or-webservice-from-vista-sidebar-gadget-by-using-silverlight/]

The challenge today is really simple. All we have to do is to write Silverlight Vista Sidebar Gadget, that consumes either WCF, ASMX or REST based service. Really simple, isn’t it? Let’s start

Build server side services

We should start from services. This is very straight forward mission. Here the logic I want to implement

public string Echo(string input)
    {
        return string.Format("ACK from {0}", input);
    }

Well, WCF? We should mark service and operation contracts. That’s all

[ServiceContract(Namespace = "")]
public class EchoService
{
    [OperationContract]
    public string Echo(string input)
    {
        return string.Format("ACK from WCF with {0}", input);
    }

}

This does not works. Why? Silverlight knows only consumes ASP.NET compatible (simplified) web services, thus we should add following attribute to the our class attributes collection

[ServiceContract(Namespace = "")]
[AspNetCompatibilityRequirements(RequirementsMode = AspNetCompatibilityRequirementsMode.Allowed)]
public class EchoService
{

Now, the service is discoverable and accessible by Silverlight. Great news. Now let’s put it into our shared host. Hmm, we got strange error: “Deploying WCF Services: This collection already contains an address with scheme http.” What the hell is it?

This is shared hosting problem. Your host provider uses virtual IP and host addresses and has number of different web services, sitting on the same shared host. How to solve it?

Simple, all you have to do is to specify your own service host factory. Here the example of classes to put into code behind

class SLHostFactory : ServiceHostFactory
{
    protected override ServiceHost CreateServiceHost(Type serviceType, Uri[] baseAddresses)
    {
        SLHost customServiceHost =
          new SLHost(serviceType, new Uri("[Your URL goes here]",UriKind.Absolute));
        return customServiceHost;
    }
}

class SLHost : ServiceHost
{
    public SLHost(Type serviceType, params Uri[] baseAddresses)
        : base(serviceType, baseAddresses)
    { }
    protected override void ApplyConfiguration()
    {
        base.ApplyConfiguration();
    }
}

And one attribute into your service tag

Factory="SLHostFactory"

Now it works. So what’s next? Build ASMX web service. This is even simpler

[WebMethod]
public string Echo(string input)
{
return string.Format("ACK from web service with {0}", input);
}

We done, now either WCF and Web services are accessible from your Silverlight application. So, add Service reference and consume it

Building client side

Inside code behind of your Silverlight project, you should define two proxies – one for Web Service and another for WCF service. Bother services implements the same interface, so it should not be a problem

ServerEcho.EchoServiceClient proxy;
WebServiceEcho.EchoWebServiceSoapClient wsProxy;
private void UserControl_Loaded(object sender, RoutedEventArgs e)
{
    proxy = new ServerEcho.EchoServiceClient();
    proxy.EchoCompleted += new EventHandler<ServerEcho.EchoCompletedEventArgs>(proxy_EchoCompleted);

    wsProxy = new SLGadget.WebServiceEcho.EchoWebServiceSoapClient();
    wsProxy.EchoCompleted += new EventHandler<SLGadget.WebServiceEcho.EchoCompletedEventArgs>(wsProxy_EchoCompleted);
}

Silverlight work only asynchronously, thus you should begin to understand, that synchronous programming is for pussies :). Consume it

private void WCF_Click(object sender, RoutedEventArgs e)
        {
            proxy.EchoAsync(txt.Text);
        }

        private void WS_Click(object sender, RoutedEventArgs e)
        {
            wsProxy.EchoAsync(txt.Text);
        }

And Update output

void wsProxy_EchoCompleted(object sender, SLGadget.WebServiceEcho.EchoCompletedEventArgs e)
        {
            txt.Text = e.Error == null ? e.Result : (e.Error.InnerException != null ? e.Error.InnerException.ToString() : e.Error.Message);
        }

        void proxy_EchoCompleted(object sender, ServerEcho.EchoCompletedEventArgs e)
        {
            txt.Text = e.Error == null ? e.Result : (e.Error.InnerException != null ? e.Error.InnerException.ToString() : e.Error.Message);
        }

Now let’s run it. What? Another error? Security? Access denied? Of cause you have no crossdomain.xml.

<?xml version="1.0"?>
<!DOCTYPE cross-domain-policy SYSTEM "http://www.macromedia.com/xml/dtds/cross-domain-policy.dtd">
<cross-domain-policy>
   <allow-access-from domain="*" />
</cross-domain-policy>

What? You have it and still getting the same error? Look into sniffer. You application is looking for other file, named clientaccesspolicy.xml. Why? According the documentation, you can use either… Hm, another bug with WCF consuming. Never mind, let’s put it too

<?xml version="1.0" encoding="utf-8"?>
<access-policy>
  <cross-domain-access>
    <policy>
      <allow-from http-request-headers="*">
        <domain uri="*"/>
      </allow-from>
      <grant-to>
        <resource path="/" include-subpaths="true"/>
      </grant-to>

    </policy>
  </cross-domain-access>
</access-policy>

Very well, now we are ready to run our application. It works! So, the only thing we should do is to pack it into MyGadget.gadget directory and put inside %userprofile%\appdata\local\microsoft\windows sidebar\gadgets together with gadget.xml manifest.

But… It stopped working… What’s the problem?

Very client side networking in Silverlight

The problem is, that SideBar executes it’s gadgets with local path, not with network path. Silverlight cannot use any network provider, when running locally. Why? Actually I do not know (maybe to prevent local applications development). so what to do?

Simple! Microsoft SideBar knows to run cross domain AJAX without any warnings and problems. So why not to use external XmlHttp from JavaScript for network access. Let’s do it

First we should initialize XMLHttpRequest object in JavaSctipt

var xObj;
        function getEchoWCF(text) {
            if(xObj == null) {
                xObj = new XMLHttpRequest();
                }
            else if(xObj) {
                xObj.abort();
            }

Then create SOAP request to WCF or WebService

var sURL = "[Path yo your service]";
            //Build SOAP
            var sReq = "<s:Envelope xmlns:s=\"http://schemas.xmlsoap.org/soap/envelope/\"><s:Body><Echo><input>"+text+"</input></Echo></s:Body></s:Envelope>";
            xObj.open("POST", sURL, true);
            xObj.setRequestHeader( "Content-Type", "text/xml; charset=utf-8" );
            xObj.setRequestHeader( "Cache-Control", "no-cache" );
…
xObj.send(sReq);

After the request created and send we should handle result. So we need an access from HTML page, hosting Silverlight object to Silverlight. Simple. “ScriptableMember - ScriptableType”, remember?

[ScriptableType]
public partial class Page : UserControl
{
…

[ScriptableMember]
public void UpdateResponse(string result)
{

Now return the result

xObj.onreadystatechange = function() {
            if (xObj.readyState === 4) {
                if (xObj.status && xObj.status === 200) {
                    var control = document.getElementById("silverlightControl");
                    control.Content.Page.UpdateResponse(xObj.responseText);
                }
            }

But this is not enough. We also should know to call Javascript from Silverlight… This is really simple

private void JS_Click(object sender, RoutedEventArgs e)
        {
            HtmlPage.Window.Invoke("getEchoWCF", txt.Text);
        }

We done. Now you can pack your Silverlight control, together with hosting HTML and Javascript into windows sidebar gadget and use it even with external network support.

Have a good day and be nice people.

Silverlight 2.0 for building Rich Internet Applications (local event)

Tamir Khason — Tue, 20 May 2008 19:23:00 GMT

[This blog was migrated. You will not be able to comment here.
The new URL of this post is http://khason.net/blog/silverlight-20-for-building-rich-internet-applications-local-event/]

If you are developing rich internet applications, web sites or just want to learn what’s new in Silverlight 2.0, you are invited to attend local (Israel) Microsoft Event 30-June 8:30 AM- 12:30 PM in ILDC (new Microsoft R&D offices in Herzliya).

I’ll speak about what is Silverlight 2.0 and what are differences between SL 1.0 and SL 2.0. How to build RIA with Silverlight 2.0. What is DeepZoom and some cool parts of this new internet technology. How to use DataBinding, LINQ and Microsoft Media Encoder. As small bonus for this part of the event, we’ll compare different technologies with Silverlight such as Flex, Flash 10, Thermo and SVG to make you understand differences, “pros and cons” of using each one of those technologies for specific and identifiable needs.

Then we’ll deep dive into DataBinding and learn about DataTemplates, Styles, Accessibility, Authoring and Usability (including differences between Silverlight and WPF approaches). We’ll also take a look into LINQ-to-SQL and SEO of Silverlight applications.

Third part of this event will be dedicated to networking and interoperability. We’ll speak about internet protocols such as ATOM, RSS, REST, JSON, XMLWS, etc and usage of those protocols by Silverlight applications. We’ll understand how WCF can assist us to make our live easier. We’ll also touch security issues of Silverlight deployment and networking such as Cross Domain Policy, progressive download and deploy-on-demand.

I can make you sure, that if ”you are in” new web technologies and want to start using (or if you already using) Silverlight 2.0 for development of your applications – come and see me. Will be fun!

Note: Only a limited number of places available, so do not wait for MS newsletter (by the end of this month). Book now and come to attend this event – it’s free! (there is parking lot in floor -2)

I want to attend “Silverlight 2.0 introduction for building rich internet applications” event (30-June 8:30 AM – 12:30 PM, ILDC Herzelia, 5, Gav-Yam str, floor L2 13,Shenkar str)

See you there…

UPD 29-Jun: Next session will take place at 23 July, 8:30 AM-12:30 PM. Register by visiting Microsoft events web application at https://msevents.microsoft.com/CUI/EventDetail.aspx?EventID=1032382418&culture=he-IL and sign up.