WCF Behavior

Common Tweaks

The maximum message size quota for incoming messages (65536) has been exceeded.- increase maxReceivedMessageSize!

Throttling: maxConcurrentCalls.

InstanceContextMode

PerCall is default (NB: goes on implementation, not interface)

[ServiceBehavior(InstanceContextMode = InstanceContextMode.PerCall)]
public class Service1 : IService

Sessions

If you use sessions, the contract must state for the client

[ServiceContract(SessionMode = SessionMode.Required)]
public interface IService

And then implement it

[ServiceBehavior(InstanceContextMode = InstanceContextMode.PerSession)]
public class Service1 : IService

If the client tries to use an open session after it expired, it gets a CommunicationObjectFaultedException. The default is 10 minutes - see ReliableSession.InactivityTimeout and Binding.ReceiveTimeout (you can set "infinite" but IIS will recycle you anyway). basicHttpBinding does not support sessions.

[OperationContract(IsInitiating = false, IsTerminating = true)]
Response Final(int number);

IsInitiating: (Default true)- create a session or use existing.
If set to false, cannot open a session.
IsTerminating: (Default false)- close a session (still need the proxy to Close)

Singleton

[ServiceBehavior(InstanceContextMode = InstanceContextMode.Single)]
public class Service1 : IService

It supports clients who uses sessions, but obviously everything must be thread-safe. You can create a self-hosted service passing in the singleton into the constructor.

Instance Behaviors

[OperationBehavior(ReleaseInstanceMode =
ReleaseInstanceMode.BeforeAndAfterCall)]
public void UpdateResource()

BeforeCall: creates new instance (disposes any existing instance)
AfterCall: disposed when finished
BerforeAndAfterCall: InstanceContextMode.PerCall (for one method while the others have sessions)

Concurrency

You can queue requests with Single concurrency (or Multiple to handle simultaneous calls)

[ServiceBehavior(ConcurrencyMode = ConcurrencyMode.Single)]
public class Service1 : IService

Reentrant is locked like Single, but can release locks which processing (inner WCF calls)

Duplex messaging

Because it does a callback, these must be ConcurrencyMode = ConcurrencyMode.Multiple or Reentrant (not single).

Transactions

See also contracts where you can specify [TransactionFlow(TransactionFlowOption.Mandatory)]

//requires transaction and will commit when finished
[OperationBehavior(TransactionScopeRequired = true)]
public void DoWork()

MSMQ transactions can't span both ends of the queue, but you can do batch transactions by adding an endpointBehavior with <transactedBatching maxBatchSize="100"/>.
On the service implementation add [ServiceBehavior(ReleaseServiceInstanceOnTransactionComplete = false)] so the instance keeps alive through the batch

Anonymous Behavior

In .Net 4.0+, you don't need a <service> configuration with endpoints at all- it can autogenerate for your contracts and schema (default for http is basicHttpBinding). Change the mappings (http default with <protocolMapping><add scheme="http" binding="wsHttpBinding" bindingConfiguration="MyBindingConfiguration"/>

Unnamed behavior elements (or name="") refer to the current service.

WCF Runtime Extensibility

You add an IEndpointBehavior which implements ApplyClient/ApplyDispatchBahvior or ApplyBindingParameters:
endpoint.Behaviors.Add(myIEndpointBehavior)

public class LoggingEndpointBehavior : IEndpointBehavior
{
    public void AddBindingParameters(ServiceEndpoint endpoint,
    BindingParameterCollection bindingParameters)
    { }
    public void ApplyClientBehavior(ServiceEndpoint endpoint, ClientRuntime clientRuntime)
    {
        //implements IClientMessageInspector
        var inspector = new MessageLogInspector();
        clientRuntime.MessageInspectors.Add(inspector);
    }
    public void ApplyDispatchBehavior(ServiceEndpoint endpoint, EndpointDispatcher endpointDispatcher)
    {
        //implements IDispatchMessageInspector
        var inspector = new MessageLogInspector();
        endpointDispatcher.DispatchRuntime.MessageInspectors.Add(inspector);
    }
    public void Validate(ServiceEndpoint endpoint)
    { }
}

IParameterInspector (BeforeCall/ AfterCall):
- Server: add in IEndpointBehavior.ApplyDispatchBehavior
- Client: add in IEndpointBehavior.ApplyClientBehavior
MessageInspectors-
on client, IClientMessageInspector (BeforeSendRequest, AfterReceiveReply),
on service, IDispatchClientInspector (AfterReceiveRequest, BeforeSendReply).
A serialized message body is a stream, so can be read only once (by ToString() or GetBody<T>())- so use a buffered copy
var buffer = request.CreateBufferedCopy(Int32.MaxValue)
var x = buffer.CreateMessage().GetBody<T>()

To modify it through a configuration file (in extensions/behaviorExtensions- the name can then be an element under endpointBehaviors/behavior/), derive from BehaviorExtensionElement (CreateBehavior())

static void