aspnetcore/test/DeploymentHelpers/Common/RetryHelper.cs

70 lines
2.3 KiB
C#

using System;
using System.Net;
using System.Net.Http;
using System.Threading;
using System.Threading.Tasks;
using Microsoft.Framework.Logging;
namespace DeploymentHelpers
{
public class RetryHelper
{
/// <summary>
/// Retries every 1 sec for 60 times by default.
/// </summary>
/// <param name="retryBlock"></param>
/// <param name="logger"></param>
/// <param name="cancellationToken"></param>
/// <param name="retryCount"></param>
public static async Task<HttpResponseMessage> RetryRequest(
Func<Task<HttpResponseMessage>> retryBlock,
ILogger logger,
CancellationToken cancellationToken = default(CancellationToken),
int retryCount = 60)
{
for (int retry = 0; retry < retryCount; retry++)
{
try
{
if (cancellationToken.IsCancellationRequested)
{
break;
}
logger.LogWarning("Retry count {retryCount}..", retry + 1);
var response = await retryBlock();
if (response.StatusCode == HttpStatusCode.ServiceUnavailable)
{
// Automatically retry on 503. May be application is still booting.
logger.LogWarning("Retrying a service unavailable error.");
continue;
}
return response; //Went through successfully
}
catch (AggregateException exception)
{
if (retry == retryCount - 1)
{
throw;
}
else
{
if (exception.InnerException is HttpRequestException
#if DNX451
|| exception.InnerException is System.Net.WebException
#endif
)
{
logger.LogWarning("Failed to complete the request : {0}.", exception.InnerException.Message);
Thread.Sleep(1 * 1000); //Wait for a while before retry.
}
}
}
}
return null;
}
}
}