private static void EndGetRequestStream <T>(IAsyncResult getRequestStreamResult)
{
ExecutionState <T> executionState = (ExecutionState <T>)getRequestStreamResult.AsyncState;
executionState.CurrentOperation = ExecutorOperation.EndGetRequestStream;
try
{
executionState.UpdateCompletedSynchronously(getRequestStreamResult.CompletedSynchronously);
executionState.ReqStream = executionState.Req.EndGetRequestStream(getRequestStreamResult);
executionState.CurrentOperation = ExecutorOperation.BeginUploadRequest;
Logger.LogInformational(executionState.OperationContext, SR.TraceUpload);
MultiBufferMemoryStream multiBufferMemoryStream = executionState.RestCMD.SendStream as MultiBufferMemoryStream;
if (multiBufferMemoryStream != null && !executionState.RestCMD.SendStreamLength.HasValue)
{
multiBufferMemoryStream.BeginFastCopyTo(executionState.ReqStream, executionState.OperationExpiryTime, EndFastCopyTo <T>, executionState);
}
else
{
// don't calculate md5 here as we should have already set this for auth purposes
executionState.RestCMD.SendStream.WriteToAsync(executionState.ReqStream, executionState.RestCMD.SendStreamLength, null /* maxLength */, false, executionState, null /* streamCopyState */, EndSendStreamCopy);
}
}
catch (Exception ex)
{
Logger.LogWarning(executionState.OperationContext, SR.TraceUploadError, ex.Message);
executionState.ExceptionRef = ExecutorBase.TranslateExceptionBasedOnParseError(ex, executionState.Cmd.CurrentResult, executionState.Resp, executionState.Cmd.ParseError);
Executor.EndOperation(executionState);
}
}
// Note for future maintainers:
// In EndOperation<T> above, this method is called and sync-Wait()'d on, with runPostProcess set to false.
// This means that, if 'runPostProcess' is ever false, this method must never hit an await point.
// This restriction is irrelevant in future versions of the library that only have an async executor.
private static async Task EndOperationAsync <T>(ExecutionState <T> executionState, bool runPostProcess)
{
Executor.FinishRequestAttempt(executionState);
try
{
// If an operation has been canceled of timed out this should overwrite any exception
Executor.CheckCancellation(executionState);
Executor.CheckTimeout(executionState, true);
// Success
if (executionState.ExceptionRef == null)
{
if (runPostProcess)
{
// Step 9 - This will not be called if an exception is raised during stream copying
await Executor.RunPostProcessAsync(executionState);
}
DisposeAndEnd <T>(executionState);
executionState.OnComplete();
return;
}
}
catch (Exception ex)
{
Logger.LogWarning(executionState.OperationContext, SR.TracePostProcessError, ex.Message);
executionState.ExceptionRef = ExecutorBase.TranslateExceptionBasedOnParseError(ex, executionState.Cmd.CurrentResult, executionState.Resp, executionState.Cmd.ParseError);
}
finally
{
try
{
if (executionState.ReqStream != null)
{
executionState.ReqStream.Dispose();
executionState.ReqStream = null;
}
if (executionState.Resp != null)
{
executionState.Resp.Close();
executionState.Resp = null;
}
}
catch (Exception)
{
// no op
}
}
ConsiderRetry <T>(executionState);
}
private static void EndFastCopyTo <T>(IAsyncResult fastCopyToResult)
{
ExecutionState <T> executionState = (ExecutionState <T>)fastCopyToResult.AsyncState;
try
{
executionState.UpdateCompletedSynchronously(fastCopyToResult.CompletedSynchronously);
MultiBufferMemoryStream multiBufferMemoryStream = (MultiBufferMemoryStream)executionState.RestCMD.SendStream;
multiBufferMemoryStream.EndFastCopyTo(fastCopyToResult);
Executor.EndSendStreamCopy(executionState);
}
catch (Exception ex)
{
Logger.LogWarning(executionState.OperationContext, SR.TraceUploadError, ex.Message);
executionState.ExceptionRef = ExecutorBase.TranslateExceptionBasedOnParseError(ex, executionState.Cmd.CurrentResult, executionState.Resp, executionState.Cmd.ParseError);
Executor.EndOperation(executionState);
}
}
private static void BeginGetResponse <T>(ExecutionState <T> executionState)
{
executionState.CurrentOperation = ExecutorOperation.BeginGetResponse;
Logger.LogInformational(executionState.OperationContext, SR.TraceGetResponse);
try
{
APMWithTimeout.RunWithTimeout(
executionState.Req.BeginGetResponse,
Executor.EndGetResponse <T>,
Executor.AbortRequest <T>,
executionState,
executionState.RemainingTimeout);
}
catch (Exception ex)
{
Logger.LogWarning(executionState.OperationContext, SR.TraceGetResponseError, ex.Message);
executionState.ExceptionRef = ExecutorBase.TranslateExceptionBasedOnParseError(ex, executionState.Cmd.CurrentResult, executionState.Resp, executionState.Cmd.ParseError);
Executor.EndOperation(executionState);
}
}
public static T ExecuteSync <T>(RESTCommand <T> cmd, IRetryPolicy policy, OperationContext operationContext)
{
// Note all code below will reference state, not params directly, this will allow common code with async executor
using (ExecutionState <T> executionState = new ExecutionState <T>(cmd, policy, operationContext))
{
bool shouldRetry = false;
TimeSpan delay = TimeSpan.Zero;
do
{
try
{
executionState.Init();
// 0. Begin Request
Executor.StartRequestAttempt(executionState);
// Steps 1-4
Executor.ProcessStartOfRequest(executionState, SR.TraceStartRequestSync);
Executor.CheckTimeout <T>(executionState, true);
}
catch (Exception ex)
{
Logger.LogError(executionState.OperationContext, SR.TraceInitRequestError, ex.Message);
// Store exception and throw here. All operations in this try would be non-retryable by default. At this point, the request is not even made.
// Therefore, we will not get extended error info. Hence ParseError doesn't matter here.
StorageException storageEx = ExecutorBase.TranslateExceptionBasedOnParseError(ex, executionState.Cmd.CurrentResult, executionState.Resp, executionState.Cmd.ParseError);
storageEx.IsRetryable = false;
executionState.ExceptionRef = storageEx;
throw executionState.ExceptionRef;
}
// Enter Retryable Section of execution
try
{
// 5. potentially upload data
if (cmd.SendStream != null)
{
executionState.CurrentOperation = ExecutorOperation.BeginGetRequestStream;
Logger.LogInformational(executionState.OperationContext, SR.TracePrepareUpload);
executionState.Req.Timeout = (int)executionState.RemainingTimeout.TotalMilliseconds;
executionState.ReqStream = executionState.Req.GetRequestStream();
executionState.CurrentOperation = ExecutorOperation.BeginUploadRequest;
Logger.LogInformational(executionState.OperationContext, SR.TraceUpload);
MultiBufferMemoryStream multiBufferMemoryStream = cmd.SendStream as MultiBufferMemoryStream;
try
{
if (multiBufferMemoryStream != null && !cmd.SendStreamLength.HasValue)
{
multiBufferMemoryStream.FastCopyTo(executionState.ReqStream, executionState.OperationExpiryTime);
}
else
{
// don't calculate md5 here as we should have already set this for auth purposes
executionState.RestCMD.SendStream.WriteToSync(executionState.ReqStream, cmd.SendStreamLength, null /* maxLength */, false, true, executionState, null /* streamCopyState */);
}
executionState.ReqStream.Flush();
executionState.ReqStream.Dispose();
executionState.ReqStream = null;
}
catch (Exception)
{
executionState.Req.Abort();
throw;
}
}
// 6. Get response
try
{
executionState.CurrentOperation = ExecutorOperation.BeginGetResponse;
Logger.LogInformational(executionState.OperationContext, SR.TraceGetResponse);
executionState.Req.Timeout = (int)executionState.RemainingTimeout.TotalMilliseconds;
executionState.Resp = (HttpWebResponse)executionState.Req.GetResponse();
executionState.CurrentOperation = ExecutorOperation.EndGetResponse;
}
catch (WebException ex)
{
Logger.LogWarning(executionState.OperationContext, SR.TraceGetResponseError, ex.Message);
executionState.Resp = (HttpWebResponse)ex.Response;
if (ex.Status == WebExceptionStatus.Timeout || executionState.ReqTimedOut)
{
throw new TimeoutException();
}
if (executionState.Resp == null)
{
throw;
}
else
{
executionState.ExceptionRef = ExecutorBase.TranslateExceptionBasedOnParseError(ex, executionState.Cmd.CurrentResult, executionState.Resp, executionState.Cmd.ParseError);
}
}
// Response
Logger.LogInformational(executionState.OperationContext, SR.TraceResponse, executionState.Cmd.CurrentResult.HttpStatusCode, executionState.Cmd.CurrentResult.ServiceRequestID, executionState.Cmd.CurrentResult.ContentMd5, executionState.Cmd.CurrentResult.Etag);
Executor.FireResponseReceived(executionState);
// 7. Do Response parsing (headers etc, no stream available here)
if (cmd.PreProcessResponse != null)
{
executionState.CurrentOperation = ExecutorOperation.PreProcess;
executionState.Result = cmd.PreProcessResponse(cmd, executionState.Resp, executionState.ExceptionRef, executionState.OperationContext);
// clear exception
executionState.ExceptionRef = null;
Logger.LogInformational(executionState.OperationContext, SR.TracePreProcessDone);
}
// 8. (Potentially reads stream from server)
executionState.CurrentOperation = ExecutorOperation.GetResponseStream;
cmd.ResponseStream = executionState.Resp.GetResponseStream();
if (!cmd.RetrieveResponseStream)
{
cmd.DestinationStream = Stream.Null;
}
if (cmd.DestinationStream != null)
{
if (cmd.StreamCopyState == null)
{
cmd.StreamCopyState = new StreamDescriptor();
}
try
{
executionState.CurrentOperation = ExecutorOperation.BeginDownloadResponse;
Logger.LogInformational(executionState.OperationContext, SR.TraceDownload);
cmd.ResponseStream.WriteToSync(cmd.DestinationStream, null /* copyLength */, null /* maxLength */, cmd.CalculateMd5ForResponseStream, false, executionState, cmd.StreamCopyState);
}
finally
{
cmd.ResponseStream.Dispose();
cmd.ResponseStream = null;
}
}
// Step 9 - This will not be called if an exception is raised during stream copying
Executor.ProcessEndOfRequest(executionState);
Executor.FinishRequestAttempt(executionState);
return(executionState.Result);
}
catch (Exception e)
{
Logger.LogWarning(executionState.OperationContext, SR.TraceGenericError, e.Message);
Executor.FinishRequestAttempt(executionState);
StorageException translatedException = ExecutorBase.TranslateExceptionBasedOnParseError(e, executionState.Cmd.CurrentResult, executionState.Resp, executionState.Cmd.ParseError);
executionState.ExceptionRef = translatedException;
Logger.LogInformational(executionState.OperationContext, SR.TraceRetryCheck, executionState.RetryCount, executionState.Cmd.CurrentResult.HttpStatusCode, translatedException.IsRetryable ? "yes" : "no", translatedException.Message);
shouldRetry = false;
if (translatedException.IsRetryable && (executionState.RetryPolicy != null))
{
executionState.CurrentLocation = Executor.GetNextLocation(executionState.CurrentLocation, cmd.LocationMode);
Logger.LogInformational(executionState.OperationContext, SR.TraceNextLocation, executionState.CurrentLocation);
IExtendedRetryPolicy extendedRetryPolicy = executionState.RetryPolicy as IExtendedRetryPolicy;
if (extendedRetryPolicy != null)
{
RetryContext retryContext = new RetryContext(
executionState.RetryCount++,
cmd.CurrentResult,
executionState.CurrentLocation,
cmd.LocationMode);
RetryInfo retryInfo = extendedRetryPolicy.Evaluate(retryContext, executionState.OperationContext);
if (retryInfo != null)
{
Logger.LogInformational(executionState.OperationContext, SR.TraceRetryInfo, retryInfo.TargetLocation, retryInfo.UpdatedLocationMode);
shouldRetry = true;
executionState.CurrentLocation = retryInfo.TargetLocation;
cmd.LocationMode = retryInfo.UpdatedLocationMode;
delay = retryInfo.RetryInterval;
}
}
else
{
shouldRetry = executionState.RetryPolicy.ShouldRetry(
executionState.RetryCount++,
cmd.CurrentResult.HttpStatusCode,
executionState.ExceptionRef,
out delay,
executionState.OperationContext);
}
if ((delay < TimeSpan.Zero) || (delay > Constants.MaximumRetryBackoff))
{
delay = Constants.MaximumRetryBackoff;
}
}
}
finally
{
if (executionState.Resp != null)
{
executionState.Resp.Close();
executionState.Resp = null;
}
}
if (!shouldRetry || (executionState.OperationExpiryTime.HasValue && (DateTime.Now + delay).CompareTo(executionState.OperationExpiryTime.Value) > 0))
{
Logger.LogError(executionState.OperationContext, shouldRetry ? SR.TraceRetryDecisionTimeout : SR.TraceRetryDecisionPolicy, executionState.ExceptionRef.Message);
throw executionState.ExceptionRef;
}
else
{
if (executionState.Cmd.RecoveryAction != null)
{
// I.E. Rewind stream etc.
executionState.Cmd.RecoveryAction(executionState.Cmd, executionState.ExceptionRef, executionState.OperationContext);
}
if (delay > TimeSpan.Zero)
{
Logger.LogInformational(executionState.OperationContext, SR.TraceRetryDelay, (int)delay.TotalMilliseconds);
Thread.Sleep(delay);
}
Logger.LogInformational(executionState.OperationContext, SR.TraceRetry);
}
Executor.FireRetrying(executionState);
}while (shouldRetry);
}
// should never get here, either return, or throw;
throw new NotImplementedException(SR.InternalStorageError);
}
private static void EndOperation <T>(ExecutionState <T> executionState)
{
Executor.FinishRequestAttempt(executionState);
try
{
// If an operation has been canceled of timed out this should overwrite any exception
Executor.CheckCancellation(executionState);
Executor.CheckTimeout(executionState, true);
// Success
if (executionState.ExceptionRef == null)
{
// Step 9 - This will not be called if an exception is raised during stream copying
Executor.ProcessEndOfRequest(executionState);
executionState.OnComplete();
return;
}
}
catch (Exception ex)
{
Logger.LogWarning(executionState.OperationContext, SR.TracePostProcessError, ex.Message);
executionState.ExceptionRef = ExecutorBase.TranslateExceptionBasedOnParseError(ex, executionState.Cmd.CurrentResult, executionState.Resp, executionState.Cmd.ParseError);
}
finally
{
try
{
if (executionState.ReqStream != null)
{
executionState.ReqStream.Dispose();
executionState.ReqStream = null;
}
if (executionState.Resp != null)
{
executionState.Resp.Close();
executionState.Resp = null;
}
}
catch (Exception)
{
// no op
}
}
// Handle Retry
try
{
StorageException translatedException = TranslateExceptionBasedOnParseError(executionState.ExceptionRef, executionState.Cmd.CurrentResult, executionState.Resp, executionState.Cmd.ParseError);
executionState.ExceptionRef = translatedException;
Logger.LogInformational(executionState.OperationContext, SR.TraceRetryCheck, executionState.RetryCount, executionState.Cmd.CurrentResult.HttpStatusCode, translatedException.IsRetryable ? "yes" : "no", translatedException.Message);
bool shouldRetry = false;
TimeSpan delay = TimeSpan.Zero;
if (translatedException.IsRetryable && (executionState.RetryPolicy != null))
{
executionState.CurrentLocation = Executor.GetNextLocation(executionState.CurrentLocation, executionState.RestCMD.LocationMode);
Logger.LogInformational(executionState.OperationContext, SR.TraceNextLocation, executionState.CurrentLocation);
IExtendedRetryPolicy extendedRetryPolicy = executionState.RetryPolicy as IExtendedRetryPolicy;
if (extendedRetryPolicy != null)
{
RetryContext retryContext = new RetryContext(
executionState.RetryCount++,
executionState.Cmd.CurrentResult,
executionState.CurrentLocation,
executionState.RestCMD.LocationMode);
RetryInfo retryInfo = extendedRetryPolicy.Evaluate(retryContext, executionState.OperationContext);
if (retryInfo != null)
{
Logger.LogInformational(executionState.OperationContext, SR.TraceRetryInfo, retryInfo.TargetLocation, retryInfo.UpdatedLocationMode);
shouldRetry = true;
executionState.CurrentLocation = retryInfo.TargetLocation;
executionState.RestCMD.LocationMode = retryInfo.UpdatedLocationMode;
delay = retryInfo.RetryInterval;
}
}
else
{
shouldRetry = executionState.RetryPolicy.ShouldRetry(
executionState.RetryCount++,
executionState.Cmd.CurrentResult.HttpStatusCode,
executionState.ExceptionRef,
out delay,
executionState.OperationContext);
}
if ((delay < TimeSpan.Zero) || (delay > Constants.MaximumRetryBackoff))
{
delay = Constants.MaximumRetryBackoff;
}
}
if (!shouldRetry || (executionState.OperationExpiryTime.HasValue && (DateTime.Now + delay).CompareTo(executionState.OperationExpiryTime.Value) > 0))
{
Logger.LogError(executionState.OperationContext, shouldRetry ? SR.TraceRetryDecisionTimeout : SR.TraceRetryDecisionPolicy, executionState.ExceptionRef.Message);
// No Retry
executionState.OnComplete();
}
else
{
if (executionState.Cmd.RecoveryAction != null)
{
// I.E. Rewind stream etc.
executionState.Cmd.RecoveryAction(executionState.Cmd, executionState.ExceptionRef, executionState.OperationContext);
}
if (delay > TimeSpan.Zero)
{
Logger.LogInformational(executionState.OperationContext, SR.TraceRetryDelay, (int)delay.TotalMilliseconds);
executionState.UpdateCompletedSynchronously(false);
if (executionState.BackoffTimer == null)
{
executionState.BackoffTimer = new Timer(
Executor.RetryRequest <T>,
executionState,
(int)delay.TotalMilliseconds,
Timeout.Infinite);
}
else
{
executionState.BackoffTimer.Change((int)delay.TotalMilliseconds, Timeout.Infinite);
}
executionState.CancelDelegate = () =>
{
// Disabling the timer here, but there is still a scenario where the user calls cancel after
// the timer starts the next retry but before it sets the CancelDelegate back to null. However, even
// if that happens, next retry will start and then stop immediately because of the cancelled flag.
Timer backoffTimer = executionState.BackoffTimer;
if (backoffTimer != null)
{
executionState.BackoffTimer = null;
backoffTimer.Dispose();
}
Logger.LogWarning(executionState.OperationContext, SR.TraceAbortRetry);
Executor.CheckCancellation(executionState);
executionState.OnComplete();
};
}
else
{
// Start next request immediately
Executor.RetryRequest <T>(executionState);
}
}
}
catch (Exception ex)
{
// Catch all ( i.e. users retry policy throws etc.)
Logger.LogWarning(executionState.OperationContext, SR.TraceRetryError, ex.Message);
executionState.ExceptionRef = ExecutorBase.TranslateExceptionBasedOnParseError(ex, executionState.Cmd.CurrentResult, executionState.Resp, executionState.Cmd.ParseError);
executionState.OnComplete();
}
}
private static void EndGetResponse <T>(IAsyncResult getResponseResult)
{
ExecutionState <T> executionState = (ExecutionState <T>)getResponseResult.AsyncState;
executionState.CurrentOperation = ExecutorOperation.EndGetResponse;
try
{
executionState.UpdateCompletedSynchronously(getResponseResult.CompletedSynchronously);
try
{
executionState.Resp = executionState.Req.EndGetResponse(getResponseResult) as HttpWebResponse;
}
catch (WebException ex)
{
Logger.LogWarning(executionState.OperationContext, SR.TraceGetResponseError, ex.Message);
executionState.Resp = (HttpWebResponse)ex.Response;
if (ex.Status == WebExceptionStatus.Timeout || executionState.ReqTimedOut)
{
throw new TimeoutException();
}
if (executionState.Resp == null)
{
throw;
}
else
{
// Store this exception for now. It will be parsed/thrown after the stream is read in step 8
executionState.ExceptionRef = ex;
}
}
Logger.LogInformational(executionState.OperationContext, SR.TraceResponse, executionState.Cmd.CurrentResult.HttpStatusCode, executionState.Cmd.CurrentResult.ServiceRequestID, executionState.Cmd.CurrentResult.ContentMd5, executionState.Cmd.CurrentResult.Etag);
Executor.FireResponseReceived(executionState);
// 7. Do Response parsing (headers etc, no stream available here)
if (executionState.RestCMD.PreProcessResponse != null)
{
executionState.CurrentOperation = ExecutorOperation.PreProcess;
try
{
executionState.Result = executionState.RestCMD.PreProcessResponse(executionState.RestCMD, executionState.Resp, executionState.ExceptionRef, executionState.OperationContext);
// clear exception
executionState.ExceptionRef = null;
Logger.LogInformational(executionState.OperationContext, SR.TracePreProcessDone);
}
catch (Exception ex)
{
executionState.ExceptionRef = ex;
}
}
Executor.CheckCancellation(executionState);
executionState.CurrentOperation = ExecutorOperation.GetResponseStream;
executionState.RestCMD.ResponseStream = executionState.Resp.GetResponseStream();
// 8. (Potentially reads stream from server)
if (executionState.ExceptionRef != null)
{
executionState.CurrentOperation = ExecutorOperation.BeginDownloadResponse;
Logger.LogInformational(executionState.OperationContext, SR.TraceDownloadError);
executionState.RestCMD.ErrorStream = new MemoryStream();
executionState.RestCMD.ResponseStream.WriteToAsync(executionState.RestCMD.ErrorStream, null /* copyLength */, null /* maxLength */, false /* calculateMd5 */, executionState, new StreamDescriptor(), EndResponseStreamCopy);
}
else
{
if (!executionState.RestCMD.RetrieveResponseStream)
{
executionState.RestCMD.DestinationStream = Stream.Null;
}
if (executionState.RestCMD.DestinationStream != null)
{
if (executionState.RestCMD.StreamCopyState == null)
{
executionState.RestCMD.StreamCopyState = new StreamDescriptor();
}
executionState.CurrentOperation = ExecutorOperation.BeginDownloadResponse;
Logger.LogInformational(executionState.OperationContext, SR.TraceDownload);
executionState.RestCMD.ResponseStream.WriteToAsync(executionState.RestCMD.DestinationStream, null /* copyLength */, null /* maxLength */, executionState.RestCMD.CalculateMd5ForResponseStream, executionState, executionState.RestCMD.StreamCopyState, EndResponseStreamCopy);
}
else
{
// Dont want to copy stream, just want to consume it so end
Executor.EndOperation(executionState);
}
}
}
catch (Exception ex)
{
Logger.LogWarning(executionState.OperationContext, SR.TracePreProcessError, ex.Message);
executionState.ExceptionRef = ExecutorBase.TranslateExceptionBasedOnParseError(ex, executionState.Cmd.CurrentResult, executionState.Resp, executionState.Cmd.ParseError);
Executor.EndOperation(executionState);
}
}
public static async Task <T> ExecuteAsync <T>(RESTCommand <T> cmd, IRetryPolicy policy, OperationContext operationContext, CancellationToken token)
{
// Note all code below will reference state, not params directly, this will allow common code with async executor
using (ExecutionState <T> executionState = new ExecutionState <T>(cmd, policy, operationContext))
using (CancellationTokenSource timeoutTokenSource = CancellationTokenSource.CreateLinkedTokenSource(token))
{
bool shouldRetry = false;
TimeSpan delay = TimeSpan.Zero;
// Create a new client
HttpClient client = HttpClientFactory.Instance;
do
{
try
{
executionState.Init();
// 0. Begin Request
Executor.StartRequestAttempt(executionState);
// Steps 1-4: Build Content/SetHeaders/
Executor.ProcessStartOfRequest(executionState, SR.TraceStartRequestAsync, timeoutTokenSource);
Executor.CheckTimeout <T>(executionState, true);
}
catch (Exception ex)
{
Logger.LogError(executionState.OperationContext, SR.TraceInitRequestError, ex.Message);
// Store exception and throw here. All operations in this try would be non-retryable by default. At this point, the request is not even made.
// Therefore, we will not get extended error info. Hence ParseError doesn't matter here.
StorageException storageEx = await ExecutorBase.TranslateExceptionBasedOnParseErrorAsync(ex, executionState.Cmd.CurrentResult, executionState.Resp, executionState.Cmd.ParseErrorAsync, token).ConfigureAwait(false);
storageEx.IsRetryable = false;
executionState.ExceptionRef = storageEx;
throw executionState.ExceptionRef;
}
// Enter Retryable Section of execution
try
{
// Send Request
executionState.CurrentOperation = ExecutorOperation.BeginGetResponse;
Logger.LogInformational(executionState.OperationContext, SR.TraceGetResponse);
executionState.Resp = await client.SendAsync(executionState.Req, HttpCompletionOption.ResponseHeadersRead, timeoutTokenSource.Token).ConfigureAwait(false);
executionState.CurrentOperation = ExecutorOperation.EndGetResponse;
// Since HttpClient wont throw for non success, manually check and populate an exception
if (!executionState.Resp.IsSuccessStatusCode)
{
// At this point, don't try to read the stream to parse the error
executionState.ExceptionRef = await Exceptions.PopulateStorageExceptionFromHttpResponseMessage(executionState.Resp, executionState.Cmd.CurrentResult, token, executionState.Cmd.ParseErrorAsync).ConfigureAwait(false);
}
Logger.LogInformational(executionState.OperationContext, SR.TraceResponse, executionState.Cmd.CurrentResult.HttpStatusCode, executionState.Cmd.CurrentResult.ServiceRequestID, executionState.Cmd.CurrentResult.ContentMd5, executionState.Cmd.CurrentResult.Etag);
Executor.FireResponseReceived(executionState);
// 7. Do Response parsing (headers etc, no stream available here)
if (cmd.PreProcessResponse != null)
{
executionState.CurrentOperation = ExecutorOperation.PreProcess;
try
{
executionState.Result = cmd.PreProcessResponse(cmd, executionState.Resp, executionState.ExceptionRef, executionState.OperationContext);
// clear exception
executionState.ExceptionRef = null;
}
catch (Exception ex)
{
executionState.ExceptionRef = ex;
}
Logger.LogInformational(executionState.OperationContext, SR.TracePreProcessDone);
}
// 8. (Potentially reads stream from server)
executionState.CurrentOperation = ExecutorOperation.GetResponseStream;
cmd.ResponseStream = await executionState.Resp.Content.ReadAsStreamAsync().ConfigureAwait(false);
// The stream is now available in ResponseStream. Use the stream to parse out the response or error
if (executionState.ExceptionRef != null)
{
executionState.CurrentOperation = ExecutorOperation.BeginDownloadResponse;
Logger.LogInformational(executionState.OperationContext, SR.TraceDownloadError);
try
{
cmd.ErrorStream = new MemoryStream();
await cmd.ResponseStream.WriteToAsync(cmd.ErrorStream, default(IBufferManager), null /* copyLength */, null /* maxLength */, false, executionState, new StreamDescriptor(), timeoutTokenSource.Token).ConfigureAwait(false);
cmd.ErrorStream.Seek(0, SeekOrigin.Begin);
executionState.ExceptionRef = StorageException.TranslateExceptionWithPreBufferedStream(executionState.ExceptionRef, executionState.Cmd.CurrentResult, stream => executionState.Cmd.ParseError(stream, executionState.Resp, null), cmd.ErrorStream, executionState.Resp);
throw executionState.ExceptionRef;
}
finally
{
cmd.ResponseStream.Dispose();
cmd.ResponseStream = null;
cmd.ErrorStream.Dispose();
cmd.ErrorStream = null;
}
}
else
{
if (!cmd.RetrieveResponseStream)
{
cmd.DestinationStream = Stream.Null;
}
if (cmd.DestinationStream != null)
{
if (cmd.StreamCopyState == null)
{
cmd.StreamCopyState = new StreamDescriptor();
}
try
{
executionState.CurrentOperation = ExecutorOperation.BeginDownloadResponse;
Logger.LogInformational(executionState.OperationContext, SR.TraceDownload);
await cmd.ResponseStream.WriteToAsync(cmd.DestinationStream, default(IBufferManager), null /* copyLength */, null /* maxLength */, cmd.CalculateMd5ForResponseStream, executionState, cmd.StreamCopyState, timeoutTokenSource.Token).ConfigureAwait(false);
}
finally
{
cmd.ResponseStream.Dispose();
cmd.ResponseStream = null;
}
}
}
await Executor.ProcessEndOfRequestAsync(executionState, token).ConfigureAwait(false);
Executor.FinishRequestAttempt(executionState);
return(executionState.Result);
}
catch (Exception e)
{
Logger.LogWarning(executionState.OperationContext, SR.TraceGenericError, e.Message);
Executor.FinishRequestAttempt(executionState);
if (e is OperationCanceledException && (executionState.OperationExpiryTime.HasValue && DateTime.Now.CompareTo(executionState.OperationExpiryTime.Value) > 0))
{
e = new TimeoutException(SR.TimeoutExceptionMessage, e);
}
StorageException translatedException = await ExecutorBase.TranslateExceptionBasedOnParseErrorAsync(e, executionState.Cmd.CurrentResult, executionState.Resp, executionState.Cmd.ParseErrorAsync, token).ConfigureAwait(false);
executionState.ExceptionRef = translatedException;
Logger.LogInformational(executionState.OperationContext, SR.TraceRetryCheck, executionState.RetryCount, executionState.Cmd.CurrentResult.HttpStatusCode, translatedException.IsRetryable ? "yes" : "no", translatedException.Message);
shouldRetry = false;
if (translatedException.IsRetryable && (executionState.RetryPolicy != null))
{
executionState.CurrentLocation = Executor.GetNextLocation(executionState.CurrentLocation, cmd.LocationMode);
Logger.LogInformational(executionState.OperationContext, SR.TraceNextLocation, executionState.CurrentLocation);
IExtendedRetryPolicy extendedRetryPolicy = executionState.RetryPolicy as IExtendedRetryPolicy;
if (extendedRetryPolicy != null)
{
RetryContext retryContext = new RetryContext(
executionState.RetryCount++,
cmd.CurrentResult,
executionState.CurrentLocation,
cmd.LocationMode);
RetryInfo retryInfo = extendedRetryPolicy.Evaluate(retryContext, executionState.OperationContext);
if (retryInfo != null)
{
Logger.LogInformational(executionState.OperationContext, SR.TraceRetryInfo, retryInfo.TargetLocation, retryInfo.UpdatedLocationMode);
shouldRetry = true;
executionState.CurrentLocation = retryInfo.TargetLocation;
cmd.LocationMode = retryInfo.UpdatedLocationMode;
delay = retryInfo.RetryInterval;
}
}
else
{
shouldRetry = executionState.RetryPolicy.ShouldRetry(
executionState.RetryCount++,
cmd.CurrentResult.HttpStatusCode,
executionState.ExceptionRef,
out delay,
executionState.OperationContext);
}
if ((delay < TimeSpan.Zero) || (delay > Constants.MaximumRetryBackoff))
{
delay = Constants.MaximumRetryBackoff;
}
}
}
finally
{
if (executionState.Resp != null)
{
executionState.Resp.Dispose();
executionState.Resp = null;
}
}
// potentially backoff
if (!shouldRetry || (executionState.OperationExpiryTime.HasValue && (DateTime.Now + delay).CompareTo(executionState.OperationExpiryTime.Value) > 0))
{
Logger.LogError(executionState.OperationContext, shouldRetry ? SR.TraceRetryDecisionTimeout : SR.TraceRetryDecisionPolicy, executionState.ExceptionRef.Message);
throw executionState.ExceptionRef;
}
else
{
// I.E. Rewind stream etc.
cmd.RecoveryAction?.Invoke(cmd, executionState.Cmd.CurrentResult.Exception, executionState.OperationContext);
if (delay > TimeSpan.Zero)
{
await Task.Delay(delay, token).ConfigureAwait(false);
}
Logger.LogInformational(executionState.OperationContext, SR.TraceRetry);
}
Executor.FireRetrying(executionState);
}while (shouldRetry);
// should never get here
throw new NotImplementedException(SR.InternalStorageError);
}
}
public static void InitRequest <T, INTERMEDIATE_TYPE>(ExecutionState <T> executionState)
{
try
{
executionState.Init();
// 0. Begin Request
TableExecutor.StartRequestAttempt(executionState);
if (TableExecutor.CheckTimeout <T>(executionState, false))
{
TableExecutor.EndOperation <T, INTERMEDIATE_TYPE>(executionState);
return;
}
lock (executionState.CancellationLockerObject)
{
if (TableExecutor.CheckCancellation(executionState))
{
TableExecutor.EndOperation <T, INTERMEDIATE_TYPE>(executionState);
return;
}
TableCommand <T, INTERMEDIATE_TYPE> tableCommandRef = executionState.Cmd as TableCommand <T, INTERMEDIATE_TYPE>;
// Execute Call
Logger.LogInformational(executionState.OperationContext, SR.TraceStartRequestAsync, tableCommandRef.Context.BaseUri);
tableCommandRef.Begin(
(res) =>
{
executionState.UpdateCompletedSynchronously(res.CompletedSynchronously);
INTERMEDIATE_TYPE tResult = default(INTERMEDIATE_TYPE);
try
{
tResult = tableCommandRef.End(res);
executionState.Result = tableCommandRef.ParseResponse(tResult, executionState.Cmd.CurrentResult, tableCommandRef);
if (executionState.Req != null)
{
DataServiceResponse dataServiceResponse = tResult as DataServiceResponse;
QueryOperationResponse queryResponse = tResult as QueryOperationResponse;
if (dataServiceResponse != null)
{
if (dataServiceResponse.IsBatchResponse)
{
// Attempt to populate response headers
if (executionState.Req != null)
{
SetExecutionStateCommandResult(executionState, dataServiceResponse);
Logger.LogInformational(executionState.OperationContext, SR.TraceResponse, executionState.Cmd.CurrentResult.HttpStatusCode, executionState.Cmd.CurrentResult.ServiceRequestID, executionState.Cmd.CurrentResult.ContentMd5, executionState.Cmd.CurrentResult.Etag);
}
}
else
{
int index = 0;
foreach (OperationResponse operationResponse in dataServiceResponse)
{
// Attempt to populate response headers
if (executionState.Req != null)
{
SetStorageCmdRequestResults(executionState.Cmd.RequestResults.ElementAt(index), operationResponse);
Logger.LogInformational(executionState.OperationContext, SR.TraceResponse, executionState.Cmd.RequestResults.ElementAt(index).HttpStatusCode, executionState.Cmd.RequestResults.ElementAt(index).ServiceRequestID, executionState.Cmd.RequestResults.ElementAt(index).ContentMd5, executionState.Cmd.RequestResults.ElementAt(index).Etag);
index++;
}
}
}
}
else if (queryResponse != null)
{
// Attempt to populate response headers
if (executionState.Req != null)
{
SetStorageCmdRequestResults(executionState.Cmd.CurrentResult, queryResponse);
Logger.LogInformational(executionState.OperationContext, SR.TraceResponse, executionState.Cmd.CurrentResult.HttpStatusCode, executionState.Cmd.CurrentResult.ServiceRequestID, executionState.Cmd.CurrentResult.ContentMd5, executionState.Cmd.CurrentResult.Etag);
}
}
}
}
catch (Exception ex)
{
Logger.LogWarning(executionState.OperationContext, SR.TraceGenericError, ex.Message);
lock (executionState.CancellationLockerObject)
{
if (executionState.CancelRequested)
{
// Ignore DSC exception if request was canceled.
return;
}
}
// Store exception and invoke callback here. All operations in this try would be non-retryable by default
if (executionState.ExceptionRef == null || !(executionState.ExceptionRef is StorageException))
{
executionState.ExceptionRef = ExecutorBase.TranslateDataServiceExceptionBasedOnParseError(ex, executionState.Cmd.CurrentResult, executionState.Cmd.ParseDataServiceError);
}
try
{
executionState.Result = tableCommandRef.ParseResponse(tResult, executionState.Cmd.CurrentResult, tableCommandRef);
// clear exception
executionState.ExceptionRef = null;
}
catch (Exception parseEx)
{
Logger.LogWarning(executionState.OperationContext, SR.TraceGenericError, ex.Message);
executionState.ExceptionRef = parseEx;
}
}
finally
{
EndOperation <T, INTERMEDIATE_TYPE>(executionState);
}
},
null);
if (tableCommandRef.Context != null)
{
executionState.CancelDelegate = tableCommandRef.Context.InternalCancel;
}
}
}
catch (Exception ex)
{
Logger.LogWarning(executionState.OperationContext, SR.TraceGenericError, ex.Message);
// Store exception and invoke callback here. All operations in this try would be non-retryable by default
if (executionState.ExceptionRef == null || !(executionState.ExceptionRef is StorageException))
{
executionState.ExceptionRef = ExecutorBase.TranslateDataServiceExceptionBasedOnParseError(ex, executionState.Cmd.CurrentResult, executionState.Cmd.ParseDataServiceError);
}
executionState.OnComplete();
}
}
public static T ExecuteSync <T, INTERMEDIATE_TYPE>(TableCommand <T, INTERMEDIATE_TYPE> cmd, IRetryPolicy policy, OperationContext operationContext)
{
// Note all code below will reference state, not params directly, this will allow common code with async executor
ExecutionState <T> executionState = new ExecutionState <T>(cmd, policy, operationContext);
TableExecutor.AcquireContext(cmd.Context, executionState);
bool shouldRetry = false;
TimeSpan delay = TimeSpan.Zero;
try
{
// Enter Retryable Section of execution
do
{
executionState.Init();
// 0. Begin Request
TableExecutor.StartRequestAttempt(executionState);
TableExecutor.CheckTimeout <T>(executionState, true);
try
{
INTERMEDIATE_TYPE tempResult = default(INTERMEDIATE_TYPE);
try
{
Logger.LogInformational(executionState.OperationContext, SR.TraceStartRequestSync, cmd.Context.BaseUri);
tempResult = cmd.ExecuteFunc();
executionState.Result = cmd.ParseResponse(tempResult, executionState.Cmd.CurrentResult, cmd);
DataServiceResponse dataServiceResponse = tempResult as DataServiceResponse;
QueryOperationResponse queryResponse = tempResult as QueryOperationResponse;
if (dataServiceResponse != null)
{
if (dataServiceResponse.IsBatchResponse)
{
// Attempt to populate response headers
if (executionState.Req != null)
{
SetExecutionStateCommandResult(executionState, dataServiceResponse);
Logger.LogInformational(executionState.OperationContext, SR.TraceResponse, executionState.Cmd.CurrentResult.HttpStatusCode, executionState.Cmd.CurrentResult.ServiceRequestID, executionState.Cmd.CurrentResult.ContentMd5, executionState.Cmd.CurrentResult.Etag);
}
}
else
{
int index = 0;
foreach (OperationResponse operationResponse in dataServiceResponse)
{
// Attempt to populate response headers
if (executionState.Req != null)
{
SetStorageCmdRequestResults(executionState.Cmd.RequestResults.ElementAt(index), operationResponse);
Logger.LogInformational(executionState.OperationContext, SR.TraceResponse, executionState.Cmd.RequestResults.ElementAt(index).HttpStatusCode, executionState.Cmd.RequestResults.ElementAt(index).ServiceRequestID, executionState.Cmd.RequestResults.ElementAt(index).ContentMd5, executionState.Cmd.RequestResults.ElementAt(index).Etag);
index++;
}
}
}
}
else if (queryResponse != null)
{
// Attempt to populate response headers
if (executionState.Req != null)
{
SetStorageCmdRequestResults(executionState.Cmd.CurrentResult, queryResponse);
Logger.LogInformational(executionState.OperationContext, SR.TraceResponse, executionState.Cmd.CurrentResult.HttpStatusCode, executionState.Cmd.CurrentResult.ServiceRequestID, executionState.Cmd.CurrentResult.ContentMd5, executionState.Cmd.CurrentResult.Etag);
}
}
}
catch (Exception ex)
{
Logger.LogWarning(executionState.OperationContext, SR.TraceGenericError, ex.Message);
// Store exception and invoke callback here. All operations in this try would be non-retryable by default
if (executionState.ExceptionRef == null || !(executionState.ExceptionRef is StorageException))
{
executionState.ExceptionRef = ExecutorBase.TranslateDataServiceExceptionBasedOnParseError(ex, executionState.Cmd.CurrentResult, executionState.Cmd.ParseDataServiceError);
}
executionState.Result = cmd.ParseResponse(tempResult, executionState.Cmd.CurrentResult, cmd);
// clear exception
executionState.ExceptionRef = null;
}
TableExecutor.FinishRequestAttempt(executionState);
Logger.LogInformational(executionState.OperationContext, SR.TraceSuccess);
return(executionState.Result);
}
catch (Exception e)
{
TableExecutor.FinishRequestAttempt(executionState);
StorageException translatedException = ExecutorBase.TranslateDataServiceExceptionBasedOnParseError(e, executionState.Cmd.CurrentResult, executionState.Cmd.ParseDataServiceError);
executionState.ExceptionRef = translatedException;
Logger.LogInformational(executionState.OperationContext, SR.TraceRetryCheck, executionState.RetryCount, executionState.Cmd.CurrentResult.HttpStatusCode, translatedException.IsRetryable ? "yes" : "no", translatedException.Message);
shouldRetry = false;
if (translatedException.IsRetryable && (executionState.RetryPolicy != null))
{
shouldRetry = executionState.RetryPolicy.ShouldRetry(
executionState.RetryCount++,
executionState.Cmd.CurrentResult.HttpStatusCode,
executionState.ExceptionRef,
out delay,
executionState.OperationContext);
if ((delay < TimeSpan.Zero) || (delay > Constants.MaximumRetryBackoff))
{
delay = Constants.MaximumRetryBackoff;
}
}
}
if (!shouldRetry || (executionState.OperationExpiryTime.HasValue && (DateTime.Now + delay).CompareTo(executionState.OperationExpiryTime.Value) > 0))
{
Logger.LogError(executionState.OperationContext, shouldRetry ? SR.TraceRetryDecisionTimeout : SR.TraceRetryDecisionPolicy, executionState.ExceptionRef.Message);
throw executionState.ExceptionRef;
}
else
{
if (executionState.Cmd.RecoveryAction != null)
{
// I.E. Rewind stream etc.
executionState.Cmd.RecoveryAction(executionState.Cmd, executionState.ExceptionRef, executionState.OperationContext);
}
Logger.LogInformational(executionState.OperationContext, SR.TraceRetryDelay, (int)delay.TotalMilliseconds);
if (delay > TimeSpan.Zero)
{
Thread.Sleep(delay);
}
Logger.LogInformational(executionState.OperationContext, SR.TraceRetry);
}
}while (shouldRetry);
// should never get here, either return, or throw;
throw new NotImplementedException(SR.InternalStorageError);
}
finally
{
ReleaseContext(cmd.Context);
}
}
private static void EndOperation <T, INTERMEDIATE_TYPE>(ExecutionState <T> executionState)
{
TableExecutor.FinishRequestAttempt(executionState);
lock (executionState.CancellationLockerObject)
{
executionState.CancelDelegate = null;
TableExecutor.CheckCancellation(executionState);
// Handle Success
if (executionState.ExceptionRef == null)
{
Logger.LogInformational(executionState.OperationContext, SR.TraceSuccess);
executionState.OnComplete();
return;
}
}
// Handle Retry
try
{
StorageException translatedException = ExecutorBase.TranslateDataServiceExceptionBasedOnParseError(executionState.ExceptionRef, executionState.Cmd.CurrentResult, executionState.Cmd.ParseDataServiceError);
executionState.ExceptionRef = translatedException;
Logger.LogInformational(executionState.OperationContext, SR.TraceRetryCheck, executionState.RetryCount, executionState.Cmd.CurrentResult.HttpStatusCode, translatedException.IsRetryable ? "yes" : "no", translatedException.Message);
bool shouldRetry = false;
TimeSpan delay = TimeSpan.Zero;
if (translatedException.IsRetryable && (executionState.RetryPolicy != null))
{
shouldRetry = executionState.RetryPolicy.ShouldRetry(
executionState.RetryCount++,
executionState.Cmd.CurrentResult.HttpStatusCode,
executionState.ExceptionRef,
out delay,
executionState.OperationContext);
if ((delay < TimeSpan.Zero) || (delay > Constants.MaximumRetryBackoff))
{
delay = Constants.MaximumRetryBackoff;
}
}
if (!shouldRetry || (executionState.OperationExpiryTime.HasValue && (DateTime.Now + delay).CompareTo(executionState.OperationExpiryTime.Value) > 0))
{
Logger.LogError(executionState.OperationContext, shouldRetry ? SR.TraceRetryDecisionTimeout : SR.TraceRetryDecisionPolicy, executionState.ExceptionRef.Message);
// No Retry
executionState.OnComplete();
}
else
{
if (executionState.Cmd.RecoveryAction != null)
{
// I.E. Rewind stream etc.
executionState.Cmd.RecoveryAction(executionState.Cmd, executionState.ExceptionRef, executionState.OperationContext);
}
if (delay > TimeSpan.Zero)
{
Logger.LogInformational(executionState.OperationContext, SR.TraceRetryDelay, (int)delay.TotalMilliseconds);
executionState.UpdateCompletedSynchronously(false);
if (executionState.BackoffTimer == null)
{
executionState.BackoffTimer = new Timer(
TableExecutor.RetryRequest <T, INTERMEDIATE_TYPE>,
executionState,
(int)delay.TotalMilliseconds,
Timeout.Infinite);
}
else
{
executionState.BackoffTimer.Change((int)delay.TotalMilliseconds, Timeout.Infinite);
}
executionState.CancelDelegate = () =>
{
// Disabling the timer here, but there is still a scenario where the user calls cancel after
// the timer starts the next retry but before it sets the CancelDelegate back to null. However, even
// if that happens, next retry will start and then stop immediately because of the cancelled flag.
Timer backoffTimer = executionState.BackoffTimer;
if (backoffTimer != null)
{
executionState.BackoffTimer = null;
backoffTimer.Dispose();
}
Logger.LogWarning(executionState.OperationContext, SR.TraceAbortRetry);
TableExecutor.CheckCancellation(executionState);
executionState.OnComplete();
};
}
else
{
// Start Next Request Immediately
Logger.LogInformational(executionState.OperationContext, SR.TraceRetry);
InitRequest <T, INTERMEDIATE_TYPE>(executionState);
}
}
}
catch (Exception ex)
{
// Catch all ( i.e. users retry policy throws etc.)
Logger.LogWarning(executionState.OperationContext, SR.TraceRetryError, ex.Message);
executionState.ExceptionRef = ExecutorBase.TranslateExceptionBasedOnParseError(ex, executionState.Cmd.CurrentResult, executionState.Resp, executionState.Cmd.ParseError);
executionState.OnComplete();
}
}