gistfile1.cs

using System;
using System.Data.Services.Client;
using System.Net;

public static class ExceptionRetriableExtension
{
   /// <summary>
   /// Retry on all exceptions except 2xx, 3xx, 4xx
   /// The 2xx is there for Table batch operations in which teh status code can be 202 even when 
   /// the call failed
   /// </summary>
   /// <param name="currentRetryCount"></param>
   /// <param name="lastException"></param>
   /// <param name="retryInterval"></param>
   /// <returns></returns>
   public static bool IsExceptionRetryable(this Exception lastException)
   {
       int statusCode = GetStatusCodeFromException(lastException);

       // Let us not retry if 2xx, 3xx, 4xx, 501 and 505 errors 
       if (statusCode == -1
           || (statusCode >= 200 && statusCode < 500)
           || statusCode == (int)HttpStatusCode.NotImplemented
           || statusCode == (int)HttpStatusCode.HttpVersionNotSupported)
       {
           return false;
       }

       return true;
   }

   /// <summary>
   /// Get the status code from exception. This can be sued for Table, Queue and Blob service
   /// </summary>
   /// <param name="e"></param>
   /// <returns></returns>
   private static int GetStatusCodeFromException(Exception e)
   {
       // Handle DataService request and client exceptions for Table service
       DataServiceRequestException dsre = e as DataServiceRequestException;
       if (dsre != null)
       {
           // Retrieve the status code:
           //  - if we have an operation response, then it is the status code of that operation response. 
           //     We can only have one response on failure and we can ignore the batch status
           //  - otherwise it is the batch status code 
           var response = dsre.Response;
           if (response != null)
           {
               return response.BatchStatusCode;
           }
       }

       DataServiceClientException dsce = e as DataServiceClientException;
       if (dsce != null)
       {
           return dsce.StatusCode;
       }

       WebException we = e as WebException;
       if (we != null)
       {
           HttpWebResponse response = we.Response as HttpWebResponse;

           // if we do not get a response, we will assume bad gateway. This is not completely true, but since it 
           // is better to retry on such errors, we make up an error code here
           return response != null ? (int)response.StatusCode : (int)HttpStatusCode.BadGateway;
       }

       // let us not retry on any other exceptions
       return -1;
   }
}