WCF Template auto-redirects

Just a post to consolidate the various information on the net regarding preventing WCF from redirecting upon a request passing or not passing a trailing slash when it differs from the UriTemplate declared on the service.

The bits needed....

First of a message inspector to check for the wcf redirect property and remove it from the Message.

	internal class 307MessageInspector :IDispatchMessageInspector
	{
	private const String RedirectPropertyName = "WebHttpRedirect";
	public object AfterReceiveRequest(ref Message request, IClientChannel channel, InstanceContext instanceContext)
	{
	// This explicitly removes WCF generated redirects caused by added/removed slash from uri templates.
	if (request.Properties.ContainsKey(RedirectPropertyName))
	{
	request.Properties.Remove(RedirectPropertyName);
	}
	return null;
	}
	public void BeforeSendReply(ref Message reply, object correlationState)
	{
	// Do nothing as we dont want to override anything in the pipeline.
	}
	}

view raw 307MessageInspector hosted with ❤ by GitHub

Next you need to implement a custom contract behavior to make sure its applied high enough up the pipeline to prevent WCF doing its usual redirect.

	internal class 307ContractBehavior : IContractBehavior
	{
	public void Validate(ContractDescription contractDescription, ServiceEndpoint endpoint)
	{
	// Not required
	}
	// Adds the 307MessageInspector to the contact to prevent 307 redirects on incorrect template match.
	public void ApplyDispatchBehavior(ContractDescription contractDescription, ServiceEndpoint endpoint, DispatchRuntime dispatchRuntime)
	{
	dispatchRuntime.MessageInspectors.Add(new 307MessageInspector());
	}
	public void ApplyClientBehavior(ContractDescription contractDescription, ServiceEndpoint endpoint, ClientRuntime clientRuntime)
	{
	// Not required
	}
	public void AddBindingParameters(ContractDescription contractDescription, ServiceEndpoint endpoint, BindingParameterCollection bindingParameters)
	{
	// Not required
	}
	}

view raw 307ContractBehavior hosted with ❤ by GitHub

Finally add it to your service host in the OnOpening override.

	protected override void OnOpening()
	{
	base.OnOpening();
	Log.Debug("Applying prevent 307 redirect behavior");
	endpoint.Contract.Behaviors.Add(new 307ContractBehavior());
	}

view raw 307SeviceHostSnippet hosted with ❤ by GitHub

And you should now find you no longer get redirected when passing an incorrect url to your WCF application.