Added retry policy interface and default linear policy

Author: TCBroad

src/HangFire.Azure.ServiceBusQueue/HangFire.Azure.ServiceBusQueue.csproj

@@ -69,6 +69,8 @@
     <Reference Include="System.Xml" />
   </ItemGroup>
   <ItemGroup>
+    <Compile Include="IRetryPolicy.cs" />
+    <Compile Include="LinearRetryPolicy.cs" />
     <Compile Include="ServiceBusQueueFetchedJob.cs" />
     <Compile Include="Properties\AssemblyInfo.cs" />
     <Compile Include="ServiceBusQueueJobQueue.cs" />

src/HangFire.Azure.ServiceBusQueue/IRetryPolicy.cs

@@ -0,0 +1,9 @@
+using System;
+
+namespace Hangfire.Azure.ServiceBusQueue
+{
+    public interface IRetryPolicy
+    {
+        void Execute(Action action);
+    }
+}

src/HangFire.Azure.ServiceBusQueue/LinearRetryPolicy.cs

@@ -0,0 +1,40 @@
+using System;
+using System.Threading;
+
+namespace Hangfire.Azure.ServiceBusQueue
+{
+    public class LinearRetryPolicy : IRetryPolicy
+    {
+        public LinearRetryPolicy(int retryCount, TimeSpan retryDelay)
+        {
+            this.RetryDelay = retryDelay;
+            this.RetryCount = retryCount;
+        }
+
+        public TimeSpan RetryDelay { get; private set; }
+
+        public int RetryCount { get; private set; }
+
+        public void Execute(Action action)
+        {
+            for (var i = 0; i < this.RetryCount; i++)
+            {
+                try
+                {
+                    action();
+
+                    return;
+                }
+                catch (TimeoutException)
+                {
+                    if (i == this.RetryCount - 1)
+                    {
+                        throw;
+                    }
+
+                    Thread.Sleep(this.RetryDelay);
+                }
+            }
+        }
+    }
+}

src/HangFire.Azure.ServiceBusQueue/ServiceBusQueueJobQueue.cs

@@ -52,7 +52,6 @@ public IFetchedJob Dequeue(string[] queues, CancellationToken cancellationToken)
                     var errorMessage = string.Format(
                         "Queue {0} could not be found. Either create the queue manually, " +
                         "or grant the Manage permission and set ServiceBusQueueOptions.CheckAndCreateQueues to true",
-
                         clients[queueIndex].Path);
 
                     throw new UnauthorizedAccessException(errorMessage, ex);
@@ -75,9 +74,9 @@ public void Enqueue(IDbConnection connection, string queue, string jobId)
 
                 using (var message = new BrokeredMessage(jobId))
                 {
-                    client.Send(message);
+                    _manager.Options.RetryPolicy.Execute(() => client.Send(message));
                 }
             }
         }
     }
-}
+}

src/HangFire.Azure.ServiceBusQueue/ServiceBusQueueOptions.cs

@@ -9,6 +9,7 @@ public ServiceBusQueueOptions()
         {
             this.CheckAndCreateQueues = true;
             this.LoopReceiveTimeout = TimeSpan.FromMilliseconds(500);
+            this.RetryPolicy = new LinearRetryPolicy(3, TimeSpan.FromSeconds(1));
         }
 
         /// <summary>
@@ -50,6 +51,15 @@ public ServiceBusQueueOptions()
         /// <value>Defaults to <c>TimeSpan.FromMilliseconds(500)</c></value>
         public TimeSpan LoopReceiveTimeout { get; set; }
 
+        /// <summary>
+        /// Gets or sets the retry policy for enqueueing messages
+        /// </summary>
+        /// <remarks>
+        /// The default policy is a <see cref="LinearRetryPolicy" /> with <see cref="LinearRetryPolicy.RetryCount"/> of 3
+        /// and a <see cref="LinearRetryPolicy.RetryDelay"/> of 1 second.
+        /// </remarks>
+        public IRetryPolicy RetryPolicy { get; set; }
+
         internal string GetQueueName(string name)
         {
             if (QueuePrefix != null)