public MessageAssembler(MethodInfo operation)
{
Operation = operation;
Parameters = operation.GetParameters();
ValidateSignature();
(ResponseType, ResponseTypeIndex, HeaderResponseType, HeaderResponseTypeInput) = GetResponseType(operation.ReturnType);
(RequestType, RequestTypeInput, HeaderRequestType, HeaderRequestTypeInput) = GetRequestType();
ContextInput = GetContextInput();
OperationType = GetOperationType();
IsAsync = ReflectionTools.IsTask(Operation.ReturnType);
}
private MethodType GetOperationType()
{
var returnType = Operation.ReturnType;
if (ReflectionTools.IsTask(returnType))
{
var args = returnType.GenericTypeArguments;
returnType = args.Length == 0 ? returnType : args[0];
}
var responseIsStreaming = ReflectionTools.IsAsyncEnumerable(returnType) ||
(ReflectionTools.IsValueTuple(returnType) && returnType.GenericTypeArguments.Any(ReflectionTools.IsAsyncEnumerable));
var requestIsStreaming = Parameters.Select(i => i.ParameterType).Any(ReflectionTools.IsAsyncEnumerable);
if (responseIsStreaming)
{
return(requestIsStreaming ? MethodType.DuplexStreaming : MethodType.ServerStreaming);
}
return(requestIsStreaming ? MethodType.ClientStreaming : MethodType.Unary);
}
private static bool IsDataParameter(Type type)
{
return(!ReflectionTools.IsTask(type) &&
!IsContextParameter(type) &&
!ReflectionTools.IsStream(type));
}
private (Type ResponseType, int Index, Type?HeaderType, int[] HeaderIndexes) GetResponseType(Type returnType)
{
if (returnType == typeof(void))
{
return(typeof(Message), 0, null, Array.Empty <int>());
}
var responseType = returnType;
if (ReflectionTools.IsTask(returnType))
{
if (!returnType.IsGenericType)
{
return(typeof(Message), 0, null, Array.Empty <int>());
}
responseType = returnType.GenericTypeArguments[0];
}
if (ReflectionTools.IsValueTuple(responseType) && responseType.GenericTypeArguments.Any(ReflectionTools.IsAsyncEnumerable))
{
if (!ReflectionTools.IsTask(returnType))
{
ThrowInvalidSignature("Wrap return type with Task<> or ValueTask<>.");
}
var genericArguments = responseType.GenericTypeArguments;
if (genericArguments.Length == 1)
{
ThrowInvalidSignature("Unwrap return type from ValueTuple<>.");
}
var streamIndex = -1;
var headerIndexes = new List <int>();
var headerTypes = new List <Type>();
for (var i = 0; i < genericArguments.Length; i++)
{
var genericArgument = genericArguments[i];
if (ReflectionTools.IsAsyncEnumerable(genericArgument))
{
responseType = genericArgument.GenericTypeArguments[0];
if (streamIndex >= 0 || IsContextParameter(responseType) || !IsDataParameter(responseType))
{
ThrowInvalidSignature();
}
streamIndex = i;
}
else if (IsContextParameter(genericArgument) || !IsDataParameter(genericArgument))
{
ThrowInvalidSignature();
}
else
{
headerIndexes.Add(i);
headerTypes.Add(genericArgument);
}
}
return(
MessageBuilder.GetMessageType(responseType),
streamIndex,
MessageBuilder.GetMessageType(headerTypes.ToArray()),
headerIndexes.ToArray());
}
if (ReflectionTools.IsAsyncEnumerable(responseType))
{
responseType = responseType.GenericTypeArguments[0];
}
if (IsContextParameter(responseType) || !IsDataParameter(responseType))
{
ThrowInvalidSignature();
}
return(MessageBuilder.GetMessageType(responseType), 0, null, Array.Empty <int>());
}
public void IsTask(Type type, bool expected)
{
ReflectionTools.IsTask(type).ShouldBe(expected);
}
