WCF Service Throttle Behavior Extension Element

using System;
using System.Linq;
using System.ServiceModel.Description;
using System.ServiceModel.Dispatcher;
using System.Threading;

namespace Common.Diagnostics
{
    /// <summary>
    /// Behavior extension to throttle WCF client requests. See <see cref="ServiceThrottleBehaviorExtension"/> to configure
    /// </summary>
    public class ServiceThrottleBehavior : IClientMessageInspector, IEndpointBehavior
    {
        public int SleepMilliseconds { get; set; }

        public ServiceThrottleBehavior(int sleepMS)
        {
            this.SleepMilliseconds = sleepMS;
        }

        public object BeforeSendRequest(ref System.ServiceModel.Channels.Message request, System.ServiceModel.IClientChannel channel)
        {
            string requestAction = ParseAction(request.Headers.Action);
            if (this.SleepMilliseconds > 0)
            {
                System.Diagnostics.Debug.WriteLine("{0} sleeping {1:N0} ms", requestAction, this.SleepMilliseconds);
                Thread.Sleep(this.SleepMilliseconds);
            }
            return null;
        }

        public void AfterReceiveReply(ref System.ServiceModel.Channels.Message reply, object correlationState)
        {

        }
        /// <summary>
        /// Gets the WCF Server name and method from the reply action header
        /// </summary>
        string ParseAction(string actionHeader)
        {
            string actionMethod = actionHeader;
            Uri actionUri = null;
            if (Uri.TryCreate(actionHeader, UriKind.Absolute, out actionUri))
            {
                actionMethod = string.Join(".", actionUri.Segments
                                                        .Where(t => !t.Equals(actionUri.Scheme))
                                                        .Where(t => !t.Equals(actionUri.Host))
                                                        .Where(t => !t.Equals("/"))
                                                        .Select(t => t.Trim('/')).ToArray());

                if (string.IsNullOrEmpty(actionMethod))
                    actionMethod = actionHeader;
            }
            return actionMethod;
        }

        public void ApplyClientBehavior(ServiceEndpoint endpoint, ClientRuntime clientRuntime)
        {
            // Add this implementation to the inspectors.
            clientRuntime.MessageInspectors.Add(this);
        }

        #region Not implemented IEndpointBehavior methods
        public void AddBindingParameters(ServiceEndpoint endpoint, System.ServiceModel.Channels.BindingParameterCollection bindingParameters) { }

        public void ApplyDispatchBehavior(ServiceEndpoint endpoint, EndpointDispatcher endpointDispatcher) { }

        public void Validate(ServiceEndpoint endpoint) { }
        #endregion

    }

    /// <summary>
    /// Extension element used to throttle service requests, used in app.config
    /// </summary>
    /// <example>
    /// <![CDATA[
    /// <extensions>
    ///     <behaviorExtensions>
    ///         <add name="serviceThrottleBehavior" type="Common.Diagnostics.ServiceThrottleBehaviorExtension, Common, Version=1.0.0.0, Culture=neutral, PublicKeyToken=null" />
    ///     </behaviorExtensions>
    /// </extensions>
    /// /*
    /// <behaviors>
    ///     <endpointBehaviors>
    ///         <behavior name="YourServiceBehavior">
    ///             <serviceThrottleBehavior sleepMilliseconds="500"/>
    ///         </behavior>
    ///     </endpointBehaviors>
    /// </behaviors>
    /// */
    ///  ]]>
    /// </example>
    public class ServiceThrottleBehaviorExtension : BehaviorExtensionElement
    {
        protected override object CreateBehavior()
        {
            return new ServiceThrottleBehavior(this.SleepMilliseconds);
        }

        public override Type BehaviorType
        {
            get
            {
                return typeof(ServiceThrottleBehavior);
            }
        }

        [ConfigurationProperty("sleepMilliseconds", DefaultValue = 0, IsRequired = false)]
        public int SleepMilliseconds
        {
            get
            {
                var raw = base["sleepMilliseconds"];
                if (raw == null)
                    return 0;
                else
                {
                    int val = 0;
                    if (int.TryParse(raw.ToString(), out val))
                        return val;
                }
                return 0;
            }
            set { base["sleepMilliseconds"] = value; }
        }
    }
}