/// <summary>
/// This method makes the actual web request and marshalls the response body or error returned from the service.
/// For some error response a retry will be attempted after an exponential pause.
/// </summary>
/// <typeparam name="X">The user facing request type.</typeparam>
/// <typeparam name="Y">The user facing response type.</typeparam>
/// <param name="request">The wrapper around the user facing request.</param>
/// <param name="signer">The type of signer to use for the request.</param>
/// <param name="unmarshaller">The object used to unmarshall the response body.</param>
/// <returns>The response object for the request</returns>
internal Y Invoke <X, Y>(IRequest <X> request, AbstractAWSSigner signer, IResponseUnmarshaller <Y, UnmarshallerContext> unmarshaller)
{
Type requestType = typeof(X);
string requestName = requestType.Name;
this.logger.DebugFormat("Starting request {0} at {1}", requestName, this.config.ServiceURL);
request.Endpoint = new Uri(this.config.ServiceURL);
signer.Sign(request, this.config, this.awsAccessKeyId, this.clearAwsSecretAccessKey, this.awsSecretAccessKey);
string queryString = AWSSDKUtils.GetParametersAsString(request.Parameters);
byte[] requestData = Encoding.UTF8.GetBytes(queryString);
this.logger.DebugFormat("Request body's content [{0}] with size {1}", queryString, requestData.Length);
int retries = 0;
while (true)
{
retries++;
try
{
HttpWebRequest webRequest = this.ConfigureWebRequest <X>(request, requestData);
try
{
Y result;
DateTime requestSent = DateTime.UtcNow;
using (HttpWebResponse httpResponse = webRequest.GetResponse() as HttpWebResponse)
{
DateTime responseReceived = DateTime.UtcNow;
this.logger.InfoFormat("Received response for {0} with status code {1} in {2} ms.", requestName, httpResponse.StatusCode, (responseReceived - requestSent).TotalMilliseconds);
XmlTextReader reader = new XmlTextReader(new StreamReader(httpResponse.GetResponseStream()));
UnmarshallerContext context = new UnmarshallerContext(reader);
result = unmarshaller.Unmarshall(context);
}
return(result);
}
catch (WebException we)
{
processWebException <X, Y>(requestName, we, webRequest, unmarshaller, request, retries);
}
}
catch (Exception e)
{
this.logger.Error(string.Format("Error configuring web request {0} to {1}.", requestName, request.Endpoint.ToString()), e);
throw;
}
}
}
private void processWebException <X, Y>(string requestName, WebException we, HttpWebRequest webRequest, IResponseUnmarshaller <Y, UnmarshallerContext> unmarshaller, IRequest <X> request, int retries)
{
HttpStatusCode statusCode;
AmazonServiceException errorResponseException = null;
using (HttpWebResponse httpErrorResponse = we.Response as HttpWebResponse)
{
if (httpErrorResponse == null)
{
// Abort the unsuccessful request
webRequest.Abort();
// If it is a keep alive error then attempt a retry
if (we != null && retries <= config.MaxErrorRetry && we.Status == WebExceptionStatus.KeepAliveFailure)
{
pauseExponentially(retries);
return;
}
throw new AmazonServiceException(we);
}
statusCode = httpErrorResponse.StatusCode;
XmlTextReader errorReader;
#if NOSTREAM
string responseBody = new StreamReader(httpErrorResponse.GetResponseStream()).ReadToEnd();;
errorReader = new XmlTextReader(new StringReader(responseBody));
#else
errorReader = new XmlTextReader(new StreamReader(httpErrorResponse.GetResponseStream()));
#endif
UnmarshallerContext errorContext = new UnmarshallerContext(errorReader);
errorResponseException = unmarshaller.UnmarshallException(errorContext, we, statusCode);
httpErrorResponse.Close();
webRequest.Abort();
if (isTemporaryRedirect(httpErrorResponse))
{
string redirectedLocation = httpErrorResponse.Headers["location"];
this.logger.InfoFormat("Request {0} is being redirected to {1}.", requestName, redirectedLocation);
request.Endpoint = new Uri(redirectedLocation);
return;
}
else if (ShouldRetry(statusCode, this.config, errorResponseException, retries))
{
this.logger.InfoFormat("Retry number {0} for request {1}.", retries, requestName);
pauseExponentially(retries);
return;
}
}
if (errorResponseException != null)
{
this.logger.Error(string.Format("Error making request {0}.", requestName), errorResponseException);
throw errorResponseException;
}
AmazonServiceException excep = new AmazonServiceException("Unable to make request", we, statusCode);
this.logger.Error(string.Format("Error making request {0}.", requestName), excep);
throw excep;
}
/// <summary>
/// This method makes the actual web request and marshalls the response body or error returned from the service.
/// For some error response a retry will be attempted after an exponential pause.
/// </summary>
/// <typeparam name="X">The user facing request type.</typeparam>
/// <typeparam name="Y">The user facing response type.</typeparam>
/// <param name="request">The wrapper around the user facing request.</param>
/// <param name="signer">The type of signer to use for the request.</param>
/// <param name="unmarshaller">The object used to unmarshall the response body.</param>
/// <returns>The response object for the request</returns>
internal Y Invoke <X, Y>(IRequest <X> request, AbstractAWSSigner signer, IResponseUnmarshaller <Y, UnmarshallerContext> unmarshaller) where X : AmazonWebServiceRequest
{
Type requestType = typeof(X);
string requestName = requestType.Name;
request.Endpoint = new Uri(this.config.ServiceURL);
request.Headers["User-Agent"] = this.config.UserAgent;
request.Headers["Content-Type"] = AWSSDKUtils.UrlEncodedContent;
ProcessRequestHandlers(request);
this.logger.DebugFormat("Starting request {0} at {1}", requestName, this.config.ServiceURL);
signer.Sign(request, this.config, this.awsAccessKeyId, this.clearAwsSecretAccessKey, this.awsSecretAccessKey);
string queryString = AWSSDKUtils.GetParametersAsString(request.Parameters);
byte[] requestData = Encoding.UTF8.GetBytes(queryString);
this.logger.DebugFormat("Request body's content [{0}] with size {1}", queryString, requestData.Length);
int retries = 0;
while (true)
{
retries++;
try
{
HttpWebRequest webRequest = this.ConfigureWebRequest <X>(request, requestData);
try
{
Y result;
DateTime requestSent = DateTime.UtcNow;
using (HttpWebResponse httpResponse = webRequest.GetResponse() as HttpWebResponse)
{
DateTime responseReceived = DateTime.UtcNow;
this.logger.InfoFormat("Received response for {0} with status code {1} in {2} ms.", requestName, httpResponse.StatusCode, (responseReceived - requestSent).TotalMilliseconds);
XmlTextReader reader;
// Using NOSTREAM is the less effcient way of dealing with the response body but it is helpful
// for debug purposes to see the entire xml body coming back from the server.
#if NOSTREAM
string responseBody = new StreamReader(httpResponse.GetResponseStream()).ReadToEnd();;
reader = new XmlTextReader(new StringReader(responseBody));
#else
reader = new XmlTextReader(new StreamReader(httpResponse.GetResponseStream()));
#endif
UnmarshallerContext context = new UnmarshallerContext(reader);
result = unmarshaller.Unmarshall(context);
}
return(result);
}
catch (WebException we)
{
processWebException <X, Y>(requestName, we, webRequest, unmarshaller, request, retries);
}
}
catch (IOException e)
{
if (this.isInnerExceptionThreadAbort(e))
{
throw;
}
this.logger.Error(string.Format("IOException making request {0} to {1}.", requestName, request.Endpoint.ToString()), e);
if (retries > this.config.MaxErrorRetry)
{
throw;
}
else
{
this.logger.Error(string.Format("IOException making request {0} to {1}. Attempting retry {2}.", requestName, request.Endpoint.ToString(), retries), e);
}
}
catch (Exception e)
{
this.logger.Error(string.Format("Error configuring web request {0} to {1}.", requestName, request.Endpoint.ToString()), e);
throw;
}
}
}
