public void StartListening(MethodInfo method, Type channel, CancellationToken cancellationToken)
{
cancellationToken.ThrowIfCancellationRequested();
HttpListener httpChannel = new HttpListener();
ChannelConfigurationInfo channelConfig = _configuration.Configure(httpChannel, channel, method, _baseURL);
//Keep the ChannelMethod open for new requests
while (true)
{
try
{
httpChannel.Start();
}
catch (HttpListenerException hle)
{
Console.WriteLine($"System.Net.HttpListenerException encountered on {channelConfig.MethodUrl} with reason :{hle.Message}");
return;
}
Console.WriteLine($"Listening on {channelConfig.MethodUrl}");
HttpListenerContext context = httpChannel.GetContext();
HttpListenerRequest request = context.Request;
HttpListenerResponse response = context.Response;
IChannelHeuristicContext heuristicsCtx = _services.Get <IChannelHeuristicContext>();
bool executedIfCached = ExecuteIfCached(channel, method, request, response, heuristicsCtx);
if (executedIfCached)
{
heuristicsCtx.Clear();
goto EndRequest;
}
LogChannel.Write(LogSeverity.Info, $"Request coming to {channelConfig.Endpoint.Name}");
LogChannel.Write(LogSeverity.Info, $"HttpMethod:{request.HttpMethod}");
bool authFailed = AuthenticationFailedIfRequired(context, request, response, channelConfig, out bool authenticated);
if (authFailed)
{
goto EndRequest;
}
//Check if the Http Method is correct
if (channelConfig.HttpMethod.ToString() != request.HttpMethod && channelConfig.HttpMethod != ChannelHttpMethod.Unknown)
{
_msgService.WrongHttpMethod(response, channelConfig.HttpMethod);
LogChannel.Write(LogSeverity.Error, "Wrong HttpMethod... Closing request");
goto EndRequest;
}
ChannelMethodInfo methodDescription = _channelMethodDescriptor.GetMethodDescription(method);
List <object> channelRequestBody = null;
ChannelMethodDeserializerFactory dsrFactory = null;
if (request.HttpMethod == "GET")
{
bool invoked = TryInvokeGetRequest(channel, method, request, response, dsrFactory, methodDescription, channelConfig, channelRequestBody, authenticated);
goto EndRequest;
}
//Enter only if Request Body is supplied with POST Method
if (request.HasEntityBody == true && request.HttpMethod == "POST")
{
StreamWriter writer = new StreamWriter(response.OutputStream);
try
{
dsrFactory = new ChannelMethodDeserializerFactory(request.InputStream);
channelRequestBody = dsrFactory.DeserializeFromBody(methodDescription, request.ContentType);
InitChannelMethodContext(channelConfig.Endpoint, request, response, authenticated, channelConfig.HttpMethod, channelRequestBody);
_requestActivator.PostActivate(channel, method, channelRequestBody, response);
}
catch (ChannelMethodContentTypeException cEx)
{
response.StatusCode = 400;
_msgService.ExceptionHandler(writer, cEx, response);
LogChannel.Write(LogSeverity.Error, cEx.Message);
}
catch (ChannelMethodParameterException pEx)
{
response.StatusCode = 400;
_msgService.ExceptionHandler(writer, pEx, response);
LogChannel.Write(LogSeverity.Error, pEx.Message);
}
catch (TargetParameterCountException tEx)
{
response.StatusCode = 400;
_msgService.ExceptionHandler(writer, tEx, response);
LogChannel.Write(LogSeverity.Error, tEx.Message);
}
catch (Exception ex)
{
response.StatusCode = 500;
_msgService.ExceptionHandler(writer, ex, response);
LogChannel.Write(LogSeverity.Fatal, ex.Message);
}
finally
{
_contextProvider.DestroyChannelMethodContext(channelConfig.Endpoint);
writer.Flush();
writer.Close();
}
}
EndRequest:
LogChannel.Write(LogSeverity.Debug, "Request finished...");
LogChannel.Write(LogSeverity.Debug, "Closing the response");
response.Close();
}
}
internal void TryInvokePostRequest(Type channel,
MethodInfo method,
HttpListenerRequest request,
HttpListenerResponse response,
List <object> channelRequestBody,
ChannelMethodInfo methodDescription,
ChannelConfigurationInfo channelConfig,
bool authenticated,
CacheExecutionResult cacheExecutionResult)
{
StreamWriter writer = new StreamWriter(response.OutputStream);
try
{
//Since request body will be processed in Heuristics if cache is enabled
//InputStream is flushed and data is already stored in Data.Parameters
//property of CacheExecutionResult
if (!cacheExecutionResult.DataProcessed)
{
_dsrFactory = new ChannelMethodDeserializerFactory(request.InputStream);
channelRequestBody = _dsrFactory.DeserializeFromBody(methodDescription, request.ContentType);
}
else
{
channelRequestBody = cacheExecutionResult.Data.Parameters;
}
InitChannelMethodContext(channelConfig.Endpoint, request, response, authenticated, channelConfig.HttpMethod, channelRequestBody);
_requestActivator.PostActivate(channel, method, channelRequestBody, response);
}
catch (ChannelMethodContentTypeException cEx)
{
response.StatusCode = 400;
_msgService.ExceptionHandler(writer, cEx, response);
LogChannel.Write(LogSeverity.Error, cEx.Message);
}
catch (ChannelMethodParameterException pEx)
{
response.StatusCode = 400;
_msgService.ExceptionHandler(writer, pEx, response);
LogChannel.Write(LogSeverity.Error, pEx.Message);
}
catch (TargetParameterCountException tEx)
{
response.StatusCode = 400;
_msgService.ExceptionHandler(writer, tEx, response);
LogChannel.Write(LogSeverity.Error, tEx.Message);
}
catch (Exception ex)
{
response.StatusCode = 500;
_msgService.ExceptionHandler(writer, ex, response);
LogChannel.Write(LogSeverity.Fatal, ex.Message);
}
finally
{
_contextProvider.DestroyChannelMethodContext(channelConfig.Endpoint);
writer.Flush();
writer.Close();
}
}
