Damir Dobric Posts

Windows Azure DevCamp Frankfurt - June 2012

2012-05-23T09:07:41Z

Erleben Sie Windows Azure wie sie es noch nie gesehen haben, direkt von der Quelle. Auf dem Windows Azure DevCamp im Sheraton Airport Congress Center in Frankfurt, erfahren Sie alles was Sie über Windows Azure wissen müssen. Es werden sowohl hochrangige Experten der Microsoft Cooperation in Redmond als auch von Microsoft in Deutschland vor Ort sein. Bekommen Sie Informationen direkt aus der Produktgruppe von Sprechern wie Karandeep Anand (Principal Group Program Manager), Wenming Ye (Senior Technical Evangelist), Scott Klein (Technical Evangelist ). Aus Deutschland werden Heike Ritter (Technical Evangelist ), Dariusz Parys (Developer Evangelist ), Patrick Heyde (Technical Evangelist) und Martin Vollmer(Senior Evangelist) mit dabei sein. Auch wenn Sie Windows Azure bereits kennen, werden Sie sicher einiges neues erfahren. Mehr Details zur Agenda folgen in Kürze an diese Stelle.

Auf dem Windows Azure DevCamp erfahren Sie:

·         wie schnell es geht Websites auf Windows Azure bereit zu stellen

·         wie Sie existierenden Code und Anwendung auf Windows Azure migrieren,
           integrieren und erweitern

·         wie Sie flexible, mehrschichtige Anwendungen erstellen

·         wie Windows Azure Dienste wie Storage, SQL Azure und der Service Bus in Ihren
           Anwendungen genutzt werden können

·         wie Sie hoch-skalierbare und schnelle Anwendungen mit Hilfe von Cloud-Diensten entwerfen

·         wie Sie Web APIs zur Anbindung von mobilen Geräten entwickeln

·         wie Sie die neusten Tools und SDKs zur Cloud-Entwicklung verwenden

Achtung: Auf Grund der internationalen Sprecher wird ein großer Teil der Veranstaltung in englischer Sprache sein.

REGISTRIERUNG:
https://msevents.microsoft.com/CUI/EventDetail.aspx?EventID=1032512581&Culture=de-DE

Error while uploading blocks in Windows Azure blob storage

2012-05-19T11:21:37Z

When trying to upload multiple blocks in the blob storage, following error can occur:

HTTP/1.1 400 The value for one of the HTTP headers is not in the correct format.
Content-Length: 321
Content-Type: application/xml
Server: Windows-Azure-Blob/1.0 Microsoft-HTTPAPI/2.0
x-ms-request-id: 3bc0487c-edb7-4d36-8243-1f39ed692ea9
x-ms-version: 2011-08-18
Date: Sat, 19 May 2012 11:13:53 GMT

<?xml version="1.0" encoding="utf-8"?><Error><Code>InvalidHeaderValue</Code><Message>The value for one of the HTTP headers is not in the correct format.
RequestId:3bc0487c-edb7-4d36-8243-1f39ed692ea9
Time:2012-05-19T11:13:54.4935587Z</Message><HeaderName>Content-Length</HeaderName><HeaderValue>0</HeaderValue></Error>

The reason why this error is related to the length of the specified block identifier. By default all block identifiers must be of the same length. However all blocks can be of different length.

For example if you have 11 blocks then identifiers should be in following format: 01, 02,..10, 11.
Following is not allowed: 1,2,3,..,10,11. In this case blocks with id 10 and 11 will fail on upload, assuming that blocks 1,2,.. etc. have already been uploaded.

Windows Azure Web Role Session Affinity (Sticky Sessions)

2012-05-17T08:56:17Z

When working with sessions in Web Applications you have consider clustered environment. That means that there will be some Load Balancer in from of server which host your application. In this cases that means that every incoming request can be routed to the different machine.
Depending on Load Balancer configuration (if feature available) there is a way to force all incoming request from one client to the same machine. This is called Sessions Affinity or Sticky Sessions. This is mostly useful feature if your application implement local cache. In this case it is required that the client remains at the same server, because routing client request to the next machine would cause inconsistent sessions state.

Windows Azure Load Balancer does not provide Sticky Sessions. This is very important to know. However if you want to use caching use AppFabric distributed cashed. Interestingly, when working with Eclipse Sticky Sessions are provided in Windows Azure.

Note that this is not Windows Azure feature. It is implemented as a IIS module which is automatically deployed by eclipse when your application is deployed. tHIS http MODULE IS CALLED Application Request Routing (ARR). This module track clients and correlates them to the right server, where they have been server for the first time. If the Windows Azure Load Balancer routes request to the machine which in term of Sticky Sessions should not server the request, the module will figure that out and reroute the request internally to the right node. For more information about this take a look here.

University of Applied Sciences in Frankfurt: Agenda for 24. Mai 2012

2012-05-17T08:29:46Z

Introduction in Windows Azure Blob Storage and queues.

Presentation: http://developers.de/media/p/303396.aspx

University of Applied Sciences in Frankfurt: - Agenda for 14.Mai 2012

2012-05-12T16:46:09Z

Agenda:

Few slides from presentation:

Code Sample: http://developers.de/media/p/302606.aspx

Presentation: http://developers.de/media/p/303098.aspx

WinDays 2012 KeyNote Demo Step Through

2012-05-12T11:54:46Z

Few days ago I showed the Demo at WinDays 2012 keynote under the name “SharePoint Ralay”. The idea of the keynote was to show some important features which never have been shown or documented in the way as of very one common industry scenario. To keep things simple we didn’t go to deep into details of SharePoint and ServiceBus. We wanted to to build a demo which will show how to build few complex and enterprise relevant scenarios, but to be in the same time interesting for most developers in audience and even for journalists who have been attending the key note.
So I decided to target three common industrial issues which daenet has been asked to solve multiple times during 2011:

1. How to get (or put) SharePoint data out of enterprise without changing of infrastructure?
2. How to build dynamic WCF contract?
3. How to build Failover cluster in 48 Seconds?

1. How to get/put data out of SPS without changing of infrastructure?

Most SharePoint Developers live in their collaborative context which mostly does not require such scenarios. But when building SharePoint solutions you will figure out that SharePoint isn’t application platform in term how one solution or enterprise architect expect to be. Today, complex systems are systems which consist of usually distributed and hybrid hybrid applications.Distributed means they at least do not run in one process and hybrid means they can be build on top of different technologies.
So, imagine now one application which is build in .NET 4.5 which should run in SharePoint. To make it more simpler image a JAVA application which runs at different machine on different geographic location. Now put it in SharePoint and let talk to each other. Application Platform is the platform which enables to do such things. Any other application platform like SharePoint, CRM, BizTalk or anything else is a platform of their own definition with huge limitations. Because of that be careful, when you say platform. “One can be a boss in his village, but just some little peace in the global world”. The part of Microsoft which build such platforms is called Business Platform Division.

So, let’s get now some data out of SharePoint in context of distributed application scenario. First of all in the world of distributed thinking, you should never allow external parties get in touch with your platform directly. To illustrate this constraint, think on giving the public access to your database. You will probably never allow somebody to send you DB-commands which will be executed against your DB (SQL Injections etc..). If you do it it is wrong and please think change it.. By following the same rule you shouldn’t let anybody to dig in your SharePoint platform for the same reason. You even should not share the secret, that you platform is SPS.

The easiest way is to provide some kind of intermediary component which will abstract the business scenario over secret platform which is running in the background. The technology which does exactly this job is WCF. We will put WCF service between SPS and external party. At some point of time when you have lot of such services, you can start to talk about Middle-Ware. This is a fine solution, but there is a still one practical problem.

The service contract could look in our case as shown below:

[ServiceContract(Name = "EchoContract", Namespace = "http://samples.microsoft.com/ServiceModel/Relay/")]
public interface ISpsRelayService
{
[OperationContract]
List<MyEntity> Query(QueryEntity query);
}

You should define the QueryEntity which somehow describes what you want. SPS developer would like to to see here probably SPS- “ClientObjects”. Unfortinatelly they have never been designed for such scenarios. They can only be used by explicit helper libraries. Such libraries do not work out of SharePoint and their dependent entities are not serializable.
But never mind, define your entities like your business needs them (see service contract above).

The service implementation (see code below) will read the QueryEntity instance and build appropriate SPS-query (not shown in the demo below).
After all we will call SPS WebService hosted internally in our enterprise at http://yourhost:44445 and finally build response as collection of MyEntity instances.
This service decouples the SPS from external parties and provides very simple and business related contract as usual in the SOA world.
Following code snippet shows how to implement the service which gets documents from some SharePOint library and returns them as collection to the external party. In fact this is nothing very complicated (not yet)..

public List<MyEntitity> Query(QueryEntity query)
{
ClientContext clientContext = new ClientContext("http://yourhost:44445");

            Web oWebsite = clientContext.Web;
            var files = oWebsite.GetFolderByServerRelativeUrl("/Shared%20Documents").Files;
            clientContext.Load(files);
            clientContext.ExecuteQuery();

List<MyEntitity> items = new List<MyEntitity>();

            foreach (var doc in files)
            {
                dynamic o = new MyEntitity();
                o.Name = doc.Name;
                o.Something = DateTime.Now.Ticks;
                o.Version = doc.UIVersionLabel;

items.Add(o);
}

return items;
}

To make it available in the internet this service needs to have a public endpoint accessible by the external party. And exactly this is the change demand in infrastructure which is very, very often an organizational issue or even “No go”. First somebody hast to give you an public IP address, then you need to configure NAT and DNS for it, then Security, port mapping from probably 80 to 4445 etc., etc..
I want to build some kind of VPN between my WCF (talking to SPS) and external caller, but without changing any piece of infrastructure. The next picture shows this scenario. Windows Azure provides a platform service called “Service Bus”. This one provides a feature called relying. Relaying can connect two participants directly thorough firewall. Two participants are connected through Service Bus intermediary by using bidirectional TCP connection, which remains open after once is established.

Following code shows how to start-up the service which will listen on Service-Bus packets and relay SharePoint to external caller.

static void Main(string[] args)
{
ServicePointManager.ServerCertificateValidationCallback = validateServerCert;

           // create the service URI based on the service namespace which you will obtain when creating the
           // service bus namespace.
          Uri address = ServiceBusEnvironment.CreateServiceUri("https", serviceNamespaceDomain, "SpsRelayService/DocumentLibrary");

          // create the credential object for the endpoint
          TransportClientEndpointBehavior sharedSecretServiceBusCredential = new TransportClientEndpointBehavior();
          sharedSecretServiceBusCredential.TokenProvider = TokenProvider.CreateSharedSecretTokenProvider(issuerName, issuerSecret);

// create the service host reading the configuration
ServiceHost host = new ServiceHost(typeof(SpsRelayService), address);

          // create the ServiceRegistrySettings behavior for the endpoint
          IEndpointBehavior serviceRegistrySettings = new ServiceRegistrySettings()
{ DisplayName = "Sharepoint Relay Document Library Service", DiscoveryMode = DiscoveryType.Public };

          foreach (ServiceEndpoint endpoint in host.Description.Endpoints)
          {

               // add the Service Bus credentials to all endpoints specified in configuration
             endpoint.Behaviors.Add(sharedSecretServiceBusCredential);

             // Optionally you can add the URI in the registry.
             endpoint.Behaviors.Add(serviceRegistrySettings);
          }

// Open the service
host.Open();

Console.ForegroundColor = ConsoleColor.Cyan;

          Console.WriteLine("Service address: " + address);
          Console.WriteLine("Press [Enter] to exit");
          Console.ReadLine();

          // close the service
          host.Close();
      }

Similarly, external party will also establish the connection as shown in the next snippet:

static void Main(string[] args)
{
ServicePointManager.ServerCertificateValidationCallback = validateServerCert;

// create the service URI based on the service namespace
Uri address = ServiceBusEnvironment.CreateServiceUri("https", serviceNamespaceDomain, "SpsRelayService/DocumentLibrary");

           // create the credential object for the endpoint
           TransportClientEndpointBehavior sharedSecretServiceBusCredential = new TransportClientEndpointBehavior();
           sharedSecretServiceBusCredential.TokenProvider = TokenProvider.CreateSharedSecretTokenProvider(issuerName, issuerSecret);

// create the channel factory loading the configuration
ChannelFactory<ISpsRelayService> channelFactory = new ChannelFactory<ISpsRelayService>("RelayEndpoint", new EndpointAddress(address));

// apply the Service Bus credentials
channelFactory.Endpoint.Behaviors.Add(/*swtBehavior*/sharedSecretServiceBusCredential);

           // create and open the client channel
           ISpsRelayService channel = channelFactory.CreateChannel();

           ((ICommunicationObject)channel).Open();

           Console.WriteLine("Enter text to echo (or [Enter] to exit):");

           string input = Console.ReadLine();

           List<MyEntity> res = channel.Query(new QueryEntity(){…});

            ((ICommunicationObject)channel).Close();

           channelFactory.Close();
       }

If you ever worked with WCF there is not much more to say. The code shown above contains a bit sugar around standard WCF.Everything else is a matter of channel which is hidden behind RelayBinding. For more information about ports in use take a look here.
Following binding must be configured in both service and client.

After you start service and then client,the client will send the request to service through firewall. The service will get data out of SPS and relay it back to the client.

2. How to build dynamic WCF contract?

In the world of SOA you always should build a clear contract between two boundaries. That means contracts like following one are not well designed:

Message Operation(Message msg);

I have also seen in some projects following variant of the similar contract, which is semantically the same one as previous one:

string Operation(string msg);

By using such contract the client has no way to know how to serialize the message. Even after the service version is changed, there is no way to communicate this to anybody instead of verbal human communication which is time intensive and error prone. Compare it with “add service reference” to create the proxy. The client and service must in such cases implement code which serializes/deserializes respectively the message (string).
In other words, using service contracted this way is called “Anti-Pattern”, which should not be used in the SOA world.

Many developers think they can build SOA solution if they are just able to build WCF based service. This is a mistake. When you use WCF it doesn’t mean at all that you are by default SOAP capable. In our scenario I will use out this fact as my advantage. Connecting external party to our relay service is not SOA focused scenario. It is more about classical EAI and not SOA. Such kind of connecting system is known as interface with point-to-point connection. This is also not the best pattern in the world of SOA (I mean point2point interface). and it should b e avoided when building middle-wares. But this is another story.

In other words, If you are connecting two systems as point2poin it might be valid to apply SOA anti-pattern.This is in context of SOA an anti-pattern, but not an anti-pattern in universe of possible solutions. If you have two parties talking to each other then you can often change the contract between them without of too much organizational difficulties.If you are changing often the contract (in our case MyEntity and MyQuery) it is easier to make it dynamic. In this case you can build it once without need to change it in the future, because it is dynamic one. Following example shows how to use ExpandoObject to build dynamic WCF contract. If you don’t know what this is take a look on Alexandra’s and Rick’s posts.

ServiceContract(Name = "SpsRelayContract", Namespace = "http://daenet.deServiceModel/Relay/")]
public interface ISpsRelayService
{
[OperationContract]
List<ExpandoObject> Query(ExpandoObject expression);
}

The good thing on Expando-contract is that you can do something like this:

dynamic o = new ExpandoObject();
               o.Name = “bla bla”;
               o.Something = DateTime.Now.Ticks;
               o.Method= new SomeDelegate(someMethod);

You can set on this object whatever property you want (more or less). But note in a case of WCF the method instance as property wouldn’t make a sense, because that instance will not exist on some other process and some other machine. However all other properties can be set as you like. And WCF will serialize them automatically for you. In other words, if you have a new property you don’t have to change contract. You just set it like:

o.NewPropery = 17;

The consumer of this value just hast to know that is there (because,. remember, there is not clear contract, Add-Reference or SVCUTIL).

As a recap, note that ExpandoObject provides a dynamic contract. Build your Service on top of this entity and you will not have to change the contract when new properties are added in the business scenario, which service implements. Remember that this is not a SOA capable solution, but it is valid to build Point-To-Point scenarios when one party is connecting to another one.

3. How to build Failover cluster in 48 Seconds?

Last but not least I there is an issue which has been mostly forgotten in almost all our discussion when building relaying scenarios. I every project you will reach a point when the solution has to be deployed in the production. Then you will ask yourself how to build redundancy based on relying? This means, you want to provide a fail-over instance of you WCF relaying service which will be used when the first one is not reachable. The picture shown bellow illustrates this requirement.

To make this working you really do not have to change any peace of infrastructure. Just start the another instance of the service on another machine. That’s all. This will work by using both protocols TCP and HTTP. There are currently few undocumented differences in routing when using different protocols, nut in general both will provide you the stable and reliable fail-over mechanism.

Remark: If you are demoing this scenario with both WCF-instances on one machine, the basicHttpRelayBinding will not work with out-of-the-box configuration, because both instances will try to start listening for contract sharing at the same address. In a case of netTcpRelayBindig this will not happen. So, the latter one can be started multiple timas at one box.

Thanks to Tomislav Tipuric director of WinDays technical track who has visionary recognized the industry need for this scenario.

TechEd 2011 Presentations

2012-05-02T15:51:44Z

Just giving URL summary of all TechEd 2011 presentations related to sessions given by my Business Platform Division colleagues. It will be be interesting to compare them with session which will be presented in few weeks at TechEd 2012.

· A Lap around Windows Azure AppFabric

· Introduction to Windows Azure AppFabric Composite Applications

· Windows Azure AppFabric Service Bus: New Capabilities

· Workflow in Windows Azure AppFabric

· Building Highly Scalable and Available WCF Services with Windows Azure AppFabric

· Windows Communication Foundation Futures

How to improve WCF?

2012-04-29T22:10:00Z

All of you who think, that there are important features for next version of WCF, you are welcome. Here is the site for feature creation of WCF 5.0 (or whatever)http://aspnet.uservoice.com/forums/147206-wcf-web-services-

University of Applied Sciences in Frankfurt: Agenda for 07.Mai 2012

2012-04-29T21:59:02Z

Presentation: http://developers.de/media/p/303098.aspx

Cloud Computing at University of Applied Sciences in Frankfurt

2012-04-29T21:55:24Z

As already announced I will start at Mai 07th.2012 with regular semester lecture at University of Applied Sciences in Frankfurt am Main. The session will be focused on cloud computing based on Windows Azure. Fortunately the content will focus common industry technology which I usually present on conferences for developers. Of course it will be slightly adopted for students and their needs.

When?

Where?

To find the the building of University of applied sciences click on the picture below?

Agenda:

Following list contains topics which I will cover in 16 hours (8 sessions). Please not that content might be slightly changed. Unfortunately at the moment it is not possible to exactly define the content of each session. However the order of topics will be probably covered in the given order. That means we will start with not very complex topics and end with more sophisticated architecture patterns.

The need for Cloud Computing
How to start?
Cloud Computing Patterns
Cloud Services
Cloud Services
Windows Azure Platform
Windows Azure Storage
Windows Azure CDN
SQL Azure Database
Reporting & Data Sync
Windows Azure AppFabric
AppFabric Caching
Windows Azure Marketplace
Virtual Machine Role
Windows Azure Connect
Windows Azure Connect
Management Portal Demo
AppFabric Composition Model
Windows Azure Platform
Moving Apps to the Cloud
Windows Azure Web & Worker Roles
Admin Mode & Startup Tasks
Virtual Machine Role
Windows Azure Connect
Windows Azure Connect
Working with SQL Azure Databases
SQL Azure Data Sync
Monthly Service Level Agreement
Windows Azure Storage
Windows Azure
Windows Azure in a Slide
Roles and Instances
Windows Azure Service Architecture
Role Programming Model
Role Lifecycle
Worker Role Patterns
Web Role
Understanding Packaging and Config
Service Definition
Service Configuration
VM Size in Windows Azure
Networking in Windows Azure
Local Storage
Configuration Values
Handling Config Changes
Monitoring
Upgrading Your Application
Storage Account
Storage in the Development Fabric
The Storage Client API
Storage Security
Storage Abstractions
Blob Storage Concepts
Blob Details
Blob Containers
Enumerating Blobs
Pagination
Two Types of Blobs Under the Hood
Uploading a Block Blob
Page Blob – Random Read/Write
Shared Access Signatures
Ad Hoc Signatures
Policy Based Signatures
Content Delivery Network (CDN)
Windows Azure Drives
Windows Azure Drive Capabilities
Drive Details
How Windows Azure Drives Works
Cloud Drive Client Library Sample
Failover with Drives
Demo
Table Storage ConceptsTable Details
Entity Properties
No Fixed Schema
Querying
Purpose of the PartitionKey
Partitions and Partition Ranges
Demo
Queue Storage ConceptsLoosely Coupled Workflow with Queues
Queue Details
Queue’s Reliable Delivery
Build your database
Deploy your database
Synchronize your data
Scale out your data
Windows Azure AppFabric / Middleware
Platform Components
Caching Service
Caching
Latency Pyramid
Problem Scenario
Caching Scenario
Cloud missing features
Cache Demo
Windows Azure AppFabric
Service Bus
Connectivity
Remoting
Eventing
Tunneling
WCF Relay Protocol Support
Architecture Patterns
Operation styles
Failover
BrokeredMessage
Managing Queues
Managing Topics
Sending to topic
Receiving from Topic

Language

Note the lecture and all content is in English, because it focuses European Master students who study in Frankfurt.

How one lesion will look like?

I will cover sessions the same way as I do at conferences. Each lesion will be consisted of Power Point (15-max. 30 slides in 1,5h) part and many practical demos. All demos will be presented in C#. For this reason it would be nice to have a knowledge of this language and .NET. Fortunately demos will not be focused on sophisticated language features and they will not have a lot of code. This way every student should be able to understand the most important code parts. We will more focus on patterns and less on language features.
If you do not know any programming language, this curse might not be optimal one.

Who can attend?

If you are regular student in Frankfurt you can by definition visit the lecture. It is your one and you already know that. If you are anybody else you will have to register for the lecture. All other students are also welcome.

How can I register ?

If you are not a student you can register by purchasing the lecture. To do that you will have to pay 21 EUR fee to GFTW and additionally 119 EUR to daenet. You can enter the class-room by showing the both receipts (überweisungsschein/letter of referral) as approval for payment. Note, members of User Group Frankfurt have an discount. Their fee is 79 EUR.

21 EUR
Gesellschaft für technische Weiterbildung
Kontonummer 369 519
Frankfurter Sparkasse BLZ 500 502 01
Verwendungszweck : “Weiterbildung Cloud Computing – DD/AP”

119 EUR (79EUR for Members of UG_Frankfurt)
daenet GmbH
Frankfurter Sparkasse
Kto. 490741, BLZ 500 502 01
Verwendungszweck : “Weiterbildung Cloud Computing – DD/AP”

Click here to register

Can I get some certificate at the end?

Yes, all attendees will get confirmation participation issued by GFTW and Microsoft (two certificates). Currently I do not know how many lessons at lest you will have to visit. If you ask me then, I would suggest you to attend all lessons.

Last but not least

I’m glad to see you there:

-Damir

Agenda for WinDays 2012 Session: Solution Architectures for Cloud, None-Cloud and Hybrid Applications Part II

2012-04-22T16:34:04Z

WHEN: 25.04.2012. 17:15 - 18:00h
WHERE: Rovinj - HALL 4

In this session you will learn about new possibilities around number of Windows Azure Services which provide new possibilities for applications running On-Premise, in the cloud or both. This demo-powered session will focus on powerful solution architecture patterns around Relaying, Tunneling, brokering with Message Queue, Topics and more.
Note that this is not Windows Azure session only. It shows platform services and new possibilities which can be achieved.The session is designed for Windows and Windows Azure developers and architects, which need to build new kind of applications with new building blocks. Even more, we will also focus on development of applications which do not run in the cloud, but make usage of Windows Azure services.

Focus of session are advanced solution architectures of hybrid and/or distributed applications which run on-premise in the cloud or both.
The coding related content is level 300 and architecture related topics might be higher like 400.

On WinDays Portal:: http://www.windays.hr/hr/raspored/technology/

Follow: http://twitter.com/#!/ddobric

Agenda for WinDays 2012 Session: Solution Architectures for Cloud, None-Cloud and Hybrid Applications Part I

2012-04-21T17:57:50Z

WHEN: 25.04.2012. | 16:10 - 16:55h
WHERE: Rovinj - HALL 4

In this session you will start to talk about need for new platform service and cloud at all. The we will take a look on a number of new possibilities around Windows Azure Platform Services which provide new possibilities for applications running On-Premise, in the cloud or both.

This demo-powered session will focus on new solution architectures based on componets like Caching, Storage and Access Control. We will see how these services work and how they can be used as components of modern applications.

Focus of session are advanced solution architectures of hybrid distributed applications which run on-premise in the clod or both.

Follow or recommend content on my blog:
http://developers.de/blogs/damir_dobric/archive/2012/04/21/agenda-for-windays-2012-session-solution-architectures-for-cloud-none-cloud-and-hybrid-applications.aspx

On WinDays Portal:: http://www.windays.hr/hr/raspored/technology/

Follow: http://twitter.com/#!/ddobric

Agenda for WinDays 2012: Power of SignaR and WebSockets with WCF 4.5 and Windows 8

2012-04-17T19:07:10Z

WHEN: 24.04.2012. 16:10 - 16:55h
WHERE: HALL 8

In this session you will learn new communication features implemented on top of WCF, ASP.NET for HTML5 and none HTML5 browsers. Come to see how WebSockets and SignalR, provided on many not only Microsoft platforms, enable amazing possibilities to build new kind of applications.
Moreover, we will talk about new duplex-based communication styles and show how to connect different kind of applications to each other in the totally connected world.
This demo powered session will give you a deeper dive in new communication technologies related products like IIS8, Windows Server 8 and Windows 8.

On WinDays Portal:: http://www.windays.hr/hr/raspored/technology/

Follow: http://twitter.com/#!/ddobric

Microsoft released source code for ASP.NET MVC, Web API and Razor

2012-04-10T19:59:25Z

Microsoft has made the source code of ASP.NET MVC available at code plex.This is definitely for the first time that Microsoft allow external developers to submit patches and code contributions for Microsoft owned stack. This sounds strange, but Microsoft development team will review for potential inclusion in the products (promise of Scott Gu ). In my opinion, this is exactly the step which can improve innovative cycle of the community. Everybody can contribute and provide new features. But, there is a powerful instance which is responsible to take a care about the quality.

Is that the step forward to get a real Open Source company? It might be, but we should not forget, the Windows Division, which follows often different set of rules.

ASP.NET WebApi Failed to load 'System.Net.Http’ Exception

2012-04-10T09:31:13Z

We have an old project (WebApplication NET3.5) which hosts few SOAP WebServices and wanted to extend it to provide some REST services for mobile devices. To do that we installed the ASP WebApi by using the NuGet package provided here: http://www.nuget.org/packages/WebApi.All. Download and installation worked fine after the project build has been set to .NET 4.0.

Unfortunately after starting of application (‘F5’) and trying to navigate to any of REST operations (in MVC term ‘actions’) the request has failed with following error:

[FileLoadException: Could not load file or assembly 'System.Net.Http, Version=2.0.0.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35' or one of its dependencies. The located assembly's manifest definition does not match the assembly reference. (Exception from HRESULT: 0x80131040)]
   System.Lazy`1.get_Value() +12777347
   System.Web.Http.WebHost.HttpControllerHandler.BeginProcessRequest(HttpContextBase httpContextBase, AsyncCallback callback, Object state) +256
   System.Web.CallHandlerExecutionStep.System.Web.HttpApplication.IExecutionStep.Execute() +405
   System.Web.HttpApplication.ExecuteStep(IExecutionStep step, Boolean& completedSynchronously) +375

The reason for this error is a mismatched project reference to System.Net.Http assembly. The project file references to public key b03f5f7f11d50a3a.

<Reference Include="System.Net.Http, Version=2.0.0.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a, processorArchitecture=MSIL">
     <Private>True</Private>
     <HintPath>..\packages\System.Net.Http.2.0.20126.16343\lib\net40\System.Net.Http.dll</HintPath>
   </Reference>

However the installed version of System.Net.Http.Dll in NuGetPackage has new token 31bf3856ad364e35'

To workaround this open the project file and change the token as shown below:

<Reference Include="System.Net.Http, Version=2.0.0.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35' , processorArchitecture=MSIL">
<Private>True</Private>
<HintPath>..\packages\System.Net.Http.2.0.20126.16343\lib\net40\System.Net.Http.dll</HintPath>
</Reference>