Specifying behaviorConfiguration in code

Wed, 19 Jul 2006 20:53:10 Z

Is there a way to set the behaviorConfiguration for a ServiceHost (or Client for that matter) in code? All examples that I've seen show it being set in app.config. I need the ability to define the behavior in the app.config, but then create the ServiceHost and endpoint objects entirely in code, passing to them the name of the config entry to use.

I do something similar now for the bindings. I define the binding configurations in the app.config, but when I create the binding in code (for example wsHttpBinding), I use the overloaded constructor that allows me to pass in the string name of the entry in the app.config. I'd like to do the same thing for services and clients.

Any ideas.

Thanks.

Bruce Bukovics
Author of .NET 2.0 Interoperability Recipes
http://www.apress.com/book/bookDisplay.html?bID=10116

Specifying behaviorConfiguration in code

Wed, 19 Jul 2006 21:14:58 Z

You can use the ServiceBehavior attribute with the ConfigurationName parameter. Is that what you're looking for?

Thanks!

Scott

Specifying behaviorConfiguration in code

Thu, 20 Jul 2006 12:18:19 Z

No, based on the documentation, it sounds like that specifies a name for the service. I want to define several standard named behaviors (not services) in my app.config. Then at runtime, I want to create my services in code (a ServiceHost) and tell them to lookup their behavior from one of the named behaviors in my app.config. The WsHttpBinding (and others) allow me to do this using one of the overloaded constructors. I'm looking for the same kind of thing for a service.

Thanks.

Bruce

Specifying behaviorConfiguration in code

Tue, 17 Oct 2006 08:03:07 Z

The original answer is right (try it!). You can use ServiceBehaviorAttribute.ConfigurationName to specify which service to look up in the config file, for example to select among S1 and S2 below...

<service name="S1"> ...

<service name="S2"> ...

Specifying behaviorConfiguration in code

Wed, 15 Nov 2006 20:40:47 Z

I'm sorry if I'm not making my problem clear. No, the original answer is not correct based on my original question. Let me try to state this problem one more time.

I am creating all of my services (ServiceHost instances) in code. I have NO entries at all in my app.config for services, and need to keep it that way. I create my using reflection. However, I do wish to have serviceBehaviors declared in my app.config such as this:

<behaviors>
    <serviceBehaviors>
        <behavior name="defaultServiceBehavior">
            <serviceThrottling maxConcurrentCalls="32"          maxConcurrentSessions="20"/>
        </behavior>
    </serviceBehaviors>
</behaviors>

So the scenario is that I only define behaviors in the app.config, not individual services. I never want to see any <service> attributes in my app.config.

When I create my ServiceHost objects (in code), I need to find a way to specify a serviceBehavior configuration name (e.g. "defaultServiceBehavior"). This is similar in concept to what I can do right now when creating bindings (also in code). For example, WSHttpBinding has a constructor that accepts the name of a binding config entry. If I construct a new WSHttpBinding("myBindingConfig"), then it uses the binding config declared in my app.config like this:

        <bindings>
            <wsHttpBinding>
                <binding name="myBindingConfig" receiveTimeout="00:10:00">
                    <security mode="None" />
                </binding>
            </wsHttpBinding>
        </bindings>

I must be missing something because this can't possibly be this difficult. There's got to be a way to specifiy serviceBehaviors in the app.config and actually reference them when creating the ServiceHost objects in code.

Thanks.

Bruce

Specifying behaviorConfiguration in code

Fri, 17 Nov 2006 14:10:18 Z

Hi,

I’m wondering if there is an easy way to read the behaviors from the app.config file and inject them into a ServiceHost object.

I can try to create a dummy service and copy de behaviors between the dummy one and the real ones but I would prefer a better solution if it’s possible.

Thanks

Specifying behaviorConfiguration in code

Fri, 17 Nov 2006 16:01:21 Z

Tolo,

I am not completely sure what you trying to accomplish but configured behaviors and their association to a ServiceHost are supported in WCF.

This example below shows how a service binds to behaviors in configuration. The service references a named behavior configuration. The behaviors declared in the named configuration will properly be "injected" into the service host. Is that what you are trying to achieve?

<?xml version="1.0" encoding="utf-8" ?>
<configuration>
<system.serviceModel>
    <services>
      <service
          name="Microsoft.ServiceModel.Samples.CalculatorService"
          behaviorConfiguration="CalculatorServiceBehavior">

        <endpoint address=""
                  binding="wsHttpBinding"
                  contract="Microsoft.ServiceModel.Samples.ICalculatorConcurrency" />

      </service>
    </services>

<behaviors>
      <serviceBehaviors>
        <behavior name="CalculatorServiceBehavior">
          <serviceMetadata httpGetEnabled="True"/>
          <serviceDebug includeExceptionDetailInFaults="False" />
        </behavior>
      </serviceBehaviors>
    </behaviors>

</system.serviceModel>

</configuration>

Specifying behaviorConfiguration in code

Fri, 17 Nov 2006 17:16:59 Z

Hi,

I know that I can configure the behaviors and the services in the configuration file, but I don’t want to do that. I need to create the ServiceHost in my code, read the configuration file and then apply the defined behaviors. I’m looking for an easy way to do it ;-)

Thanks

Specifying behaviorConfiguration in code

Fri, 17 Nov 2006 17:25:53 Z

Where are the behaviors defined? In the configuration file?

What are you reading from the configuration file?

Specifying behaviorConfiguration in code

Sat, 18 Nov 2006 00:42:51 Z

I have merged another thread with a similar question.

Bruce, unfortunately I think it may be the case that we do not offer any convenient OM for what you want to do. Note that we know of scenarios for using <binding>s without using a <service>, but I don't think we feel we know a reason for wanting to use <behavior>s without a <service>. Can you describe your motivation for not putting the <service> stuff in your app.config?

See the another post in this thread by Tolo for one possible workaround; you can configure a "dummy" <service>, new up a dummy ServiceHost, and invoke it's ApplyConfiguration in order to force the dummy to load behaviors, and then copy the behaviors over from the dummy.

Specifying behaviorConfiguration in code

Sat, 18 Nov 2006 02:02:38 Z

Hi,

I have created a class to load the behaviors. I did not have time to fully test it, so be careful.

To use it you need to define a IBehaviorFactory for each Behavior class that you want to handle (see ServiceMetadataBehaviorFactory) and then register that class to associate it with its configuration element. For example:

BehaviorsLoader.RegisterBehaviorFactory(typeof(ServiceMetadataPublishingElement), new ServiceMetadataBehaviorFactory());

And to use it:

BehaviorsLoader.LoadBehavior(svh, behaviorName);

/// <summary>

/// Used to create the IServiceBehavior using the BehaviorExtensionElement information

/// </summary>

public interface IBehaviorFactory

{

IServiceBehavior Create(BehaviorExtensionElement element);

}

/// <summary>

/// Helper class to load behaviors into a sevicehost object

/// </summary>

public static class BehaviorsLoader

{

static Dictionary<Type, IBehaviorFactory> equivalences = new Dictionary<Type, IBehaviorFactory>();

/// <summary>

/// Associate the BehaviorExtensionElement elements with the right factorie

/// </summary>

/// <param name="elementType"></param>

/// <param name="factory"></param>

static public void RegisterBehaviorFactory(Type elementType, IBehaviorFactory factory)

{

equivalences[elementType] = factory;

}

/// <summary>

/// Load the behavior in a ServiceHost object

/// </summary>

/// <param name="host"></param>

/// <param name="behaviorName"></param>

static public void LoadBehavior(ServiceHost host, string behaviorName)

{

ServiceBehaviorElement behaviorElement = GetServiceBehaviorElement(behaviorName);

if (behaviorElement != null)

{

BehaviorExtensionElement element = behaviorElement[0];

IBehaviorFactory factory = ResolveElement(element.GetType());

if (factory != null)

{

IServiceBehavior obj = factory.Create(element);

if (obj!=null)

{

// Type registered?, remove it before add the new behavior

if (host.Description.Behaviors.Contains(obj.GetType()))

host.Description.Behaviors.Remove(obj.GetType());

host.Description.Behaviors.Add(obj);

}

/// <summary>

/// Locate the IBehaviorFactory associated to elementType

/// </summary>

/// <param name="elementType"></param>

/// <returns></returns>

static IBehaviorFactory ResolveElement(Type elementType)

{

IBehaviorFactory factory;

if(equivalences.TryGetValue(elementType, out factory))

return factory;

return null;

}

static ServiceBehaviorElement GetServiceBehaviorElement(string behaviorName)

{

ServiceBehaviorElement element = null;

if (!string.IsNullOrEmpty(behaviorName))

{

BehaviorsSection secBehavior = (BehaviorsSection)ConfigurationManager.GetSection("system.serviceModel/behaviors");

if (secBehavior.ServiceBehaviors.ContainsKey(behaviorName))

element = secBehavior.ServiceBehaviors[behaviorName];

}

return element;

}

/// <summary>

/// ServiceMetadataBehaviorFactory

/// </summary>

public class ServiceMetadataBehaviorFactory: IBehaviorFactory

{

#region IBehaviorFactory Members

public IServiceBehavior Create(BehaviorExtensionElement element)

{

ServiceMetadataPublishingElement metElement = element as ServiceMetadataPublishingElement;

if(metElement==null)

return null;

ServiceMetadataBehavior behavior = new ServiceMetadataBehavior();

behavior.HttpGetEnabled = metElement.HttpGetEnabled;

behavior.HttpGetUrl = metElement.HttpGetUrl;

return behavior;

}

#endregion

}

Specifying behaviorConfiguration in code

Mon, 20 Nov 2006 14:42:01 Z

It seems that Tolo and I are asking for exactly the same thing. We need a way to create ServiceHost instances in code but load the associated behaviors from entries in the App.config.

My reason for this need is due to the way we are declaring our services. We use custom attributes on our service interfaces to provide additional meta data about each service. We then use reflection at runtime to identify all services within each assembly and create ServiceHost instances based on the additional meta data that we've provided. On the client side I create proxies instead of ServiceHost objects. The service host as well as the client application only need to know the list of assemblies to load at runtime.

The one disadvantage to our approach is that we are now declaring much of the service configuration as compiled meta data with each service instead of placing it in an app.config. This does require a change to the source if you want to change an attribute of the service. However, this does improve the development experience. It makes the development of each service much easier since you simply need to add one additional attribute to the service. You don't have to add anything to the client or service host app.config. If you are developing a lot of independent services, that is important. And, it prevents someone from modifying the most important service attributes externally. For us, it is important that our applications work the same way every time, no matter where they are deployed. Defining the services internally as compiled metadata ensures that we always know exactly what bindings, endpoints and other important attributes are in use.

So that's the reason why I'm doing this. I'll take a look at Tolo's code and see if I can make use of it in my framework.

Thanks for your help.

Bruce Bukovics
.NET 2.0 Interoperability Recipes http://www.apress.com/book/bookDisplay.html?bID=10116
Pro WF: Windows Workflow in .NET 3.0 http://www.apress.com/book/bookDisplay.html?bID=10213

Specifying behaviorConfiguration in code

Fri, 17 Oct 2008 13:46:01 Z

I am trying to do the same thing and my friend came up with this code for me and it works great!

To use it put the WCFAppConfigUtility class somewhere in your Utility section and then to use it just call Add Behavior. Works like a charm.

private void AddBehavior(string behaviorConfiguration)
{
    Dictionary<Type, object> behaviors =
        WCFAppConfigUtility.GetServiceBehavior(behaviorConfiguration);
    foreach (Type bType in behaviors.Keys)
    {
        _host.Description.Behaviors.Remove(bType);
        _host.Description.Behaviors.Add((IServiceBehavior)behaviors[bType]);
    }
}

public static partial class WCFAppConfigUtility
{
    /// <summary>
    /// Gets a listing of the service behaviors that correspond to the <paramref name="name"/>
    /// inside of App.Config.
    /// </summary>
    /// <param name="name">The name.</param>
    /// <returns>A list of all behaviors tied to <paramref name="name"/> inside of App.Config.</returns>
    /// <exception cref="ApplicationException">Occurs when the <paramref name="name"/> is not located in the App.Config.</exception>
    public static Dictionary<Type, object> GetServiceBehavior(string name)
    {
        Dictionary<Type, object> behaviorList = new Dictionary<Type, object>();
        using (DisposableSemaphore sem = DisposableSemaphore.CreateSingle(UniqueName))
        {
            Configuration config = GetConfiguration();
            BehaviorsSection behaviorData = (BehaviorsSection)config.GetSection("system.serviceModel/behaviors");
            if (!behaviorData.ServiceBehaviors.ContainsKey(name))
                throw new ApplicationException(string.Format("Service Behavior {0} was not found.", name));
            ServiceBehaviorElement serviceElement = behaviorData.ServiceBehaviors[name];
            foreach (BehaviorExtensionElement behaviorPart in serviceElement)
            {
                behaviorList.Add(behaviorPart.BehaviorType, behaviorPart.CreateBehavior());
            }
        }
        return behaviorList;
    }
}

public static class System_ServiceModel_Configuration_BehaviorExtensionElement_Extension
{
    /// <summary>
    /// Creates a behavior extension based on the current configuration settings. This is
    /// accomplished by exposing the internal protected method BehaviorExtensionElement.CreateBehavior
    /// through Reflection.
    /// </summary>
    /// <param name="element">The element.</param>
    /// <returns>The behavior extension.</returns>
    public static object CreateBehavior(this BehaviorExtensionElement element)
    {
        return element.GetType().GetMethod("CreateBehavior",
            System.Reflection.BindingFlags.Instance |
            System.Reflection.BindingFlags.NonPublic).Invoke(
                element, new object[0] { });
    }
}