void IInterceptor.Intercept(IInvocation invocation)
{
try
{
// Get the AsyncServiceMethodInfo of the method to call.
AsyncServiceMethodInfo asyncServiceMethodInfo = AsyncServiceMethodInfos.GetOrAdd(
invocation.Method,
AsyncServiceMethodInfoFactory.CreateFromMethodInfo);
// Get the (optional) parameter for the method call.
//object requestObject = invocation.Arguments.Length == 0 ? null : invocation.Arguments[0];
ParameterInfo[] parameters = invocation.Method.GetParameters();
if (parameters.Length != invocation.Arguments.Length)
{
throw new InvalidOperationException("Hm. The number of method parameters doesn't match the number of arguments...");
}
CallParam[] callParams = parameters
.Zip(invocation.Arguments, (param, arg) => new CallParam(param.Name, param.ParameterType, arg))
.ToArray();
// Call the service (as a task, i.e. the work is not performed right here but at the next await or GetResult statement).
Task <object> taskOfObject = _serverCaller.Call(asyncServiceMethodInfo, callParams);
// Get a convert method from Task<object> to Task<T> where T is the actual return type of this particular method.
MethodInfo specificConvertMethod = SpecificConvertTaskMethods.GetOrAdd(
asyncServiceMethodInfo.ReturnType,
GenericConvertTaskMethod.MakeGenericMethod(asyncServiceMethodInfo.ReturnType));
// Convert the Task<object> to Task<T>.
object taskOfT = specificConvertMethod.Invoke(null, new object[] { taskOfObject });
// Assign the resulting Task<T> as the return value.
invocation.ReturnValue = taskOfT;
}
catch (Exception exception)
{
// Crikey!
Debug.WriteLine($"Exception in {nameof(ServiceInterceptor)} calling {invocation.Method.Name} on the service {invocation.Method.DeclaringType}: \r\n{exception}");
Debugger.Break();
throw;
}
}
public async Task <object> Call(AsyncServiceMethodInfo asyncServiceMethodInfo, CallParam[] callParams)
{
try
{
// Get the URI for the HTTP server call.
ServerPath path = ServerPaths.GetServerPath(asyncServiceMethodInfo);
using (var httpClient = new HttpClient())
{
using (HttpContent content = HttpContentSupport.Create(callParams))
{
HttpResponseMessage response = await httpClient.PostAsync(_rootUri + path, content).ConfigureAwait(false);
if (!response.IsSuccessStatusCode)
{
throw new ServerCallException(asyncServiceMethodInfo, response.StatusCode);
}
using (Stream responseStream = await response.Content.ReadAsStreamAsync().ConfigureAwait(false))
{
if (responseStream == null)
{
throw new ServerCallException(asyncServiceMethodInfo, HttpStatusCode.NoContent);
}
using (var reader = new StreamReader(responseStream, Encoding.UTF8))
{
string responseJson = await reader.ReadToEndAsync().ConfigureAwait(false);
return(JsonConvert.DeserializeObject(responseJson, asyncServiceMethodInfo.ReturnType));
}
}
}
}
}
catch (Exception exception)
{
throw new ServerCallException(asyncServiceMethodInfo, "Exception during server method call", exception);
}
}
public ServiceMethod(object instance, MethodInfo methodInfo, AsyncServiceMethodInfo asyncServiceMethodInfo)
{
Instance = instance;
MethodInfo = methodInfo;
AsyncServiceMethodInfo = asyncServiceMethodInfo;
}
public ServerCallException(AsyncServiceMethodInfo serviceMethodInfo, HttpStatusCode statusCode)
{
ServiceMethodInfo = serviceMethodInfo;
StatusCode = statusCode;
}
public ServerCallException(AsyncServiceMethodInfo serviceMethodInfo, string message, Exception innerException)
: base(message, innerException)
{
ServiceMethodInfo = serviceMethodInfo;
}
