public Task MapAsync(Func <IContainer> container, Type type, MethodInfo method, Routing.Route route)
{
container.ThrowIfNull("container");
type.ThrowIfNull("type");
method.ThrowIfNull("method");
route.ThrowIfNull("route");
route.RespondWithNoContent();
return(Task.Factory.Empty());
}
public Task MapAsync(Func <IContainer> container, Type type, MethodInfo method, Routing.Route route)
{
container.ThrowIfNull("container");
type.ThrowIfNull("type");
method.ThrowIfNull("method");
route.ThrowIfNull("route");
bool methodReturnTypeImplementsIResponse = method.ReturnType.ImplementsInterface <IResponse>();
bool methodReturnTypeIsTaskT = method.ReturnType.IsGenericType && method.ReturnType.GetGenericTypeDefinition() == typeof(Task <>);
bool methodReturnTypeIsVoid = method.ReturnType == typeof(void);
if (methodReturnTypeImplementsIResponse)
{
ParameterInfo[] parameterInfos = method.GetParameters();
ParameterExpression instanceParameterExpression = Expression.Parameter(typeof(object), "instance");
ParameterExpression parametersParameterExpression = Expression.Parameter(typeof(object[]), "parameters");
UnaryExpression unaryExpression =
Expression.Convert(
Expression.Call(
Expression.Convert(instanceParameterExpression, type),
method,
parameterInfos.Select((arg, index) => Expression.Convert(
Expression.ArrayIndex(parametersParameterExpression, Expression.Constant(index)),
arg.ParameterType))),
typeof(IResponse));
Func <object, object[], IResponse> @delegate = Expression.Lambda <Func <object, object[], IResponse> >(unaryExpression, instanceParameterExpression, parametersParameterExpression).Compile();
route.RespondWith(
async context =>
{
object instance;
try
{
instance = container().GetInstance(type);
}
catch (Exception exception)
{
throw new ApplicationException(String.Format("Unable to resolve instance of type {0}.", type.FullName), exception);
}
if (instance == null)
{
throw new ApplicationException(String.Format("Unable to resolve instance of type {0}.", type.FullName));
}
var parameterValueRetriever = new ParameterValueRetriever(_parameterMappers);
object[] parameterValues = (await parameterValueRetriever.GetParameterValuesAsync(context, type, method)).ToArray();
return(@delegate(instance, parameterValues));
},
method.ReturnType);
}
else if (methodReturnTypeIsTaskT)
{
ParameterInfo[] parameterInfos = method.GetParameters();
ParameterExpression instanceParameterExpression = Expression.Parameter(typeof(object), "instance");
ParameterExpression parametersParameterExpression = Expression.Parameter(typeof(object[]), "parameters");
Type methodGenericArgumentType = method.ReturnType.GetGenericArguments()[0];
MethodInfo upcastMethodInfo = typeof(TaskExtensions)
.GetMethod("Upcast", BindingFlags.Static | BindingFlags.Public)
.MakeGenericMethod(methodGenericArgumentType, typeof(IResponse));
UnaryExpression unaryExpression =
Expression.Convert(
Expression.Call(
upcastMethodInfo,
Expression.Call(
Expression.Convert(instanceParameterExpression, type),
method,
parameterInfos.Select((arg, index) => Expression.Convert(
Expression.ArrayIndex(parametersParameterExpression, Expression.Constant(index)),
arg.ParameterType)))),
upcastMethodInfo.ReturnType);
Func <object, object[], Task <IResponse> > @delegate = Expression.Lambda <Func <object, object[], Task <IResponse> > >(unaryExpression, instanceParameterExpression, parametersParameterExpression).Compile();
route.RespondWith(
async context =>
{
object instance;
try
{
instance = container().GetInstance(type);
}
catch (Exception exception)
{
throw new ApplicationException(String.Format("Unable to resolve instance of type {0}.", type.FullName), exception);
}
if (instance == null)
{
throw new ApplicationException(String.Format("Unable to resolve instance of type {0}.", type.FullName));
}
var parameterValueRetriever = new ParameterValueRetriever(_parameterMappers);
object[] parameterValues = (await parameterValueRetriever.GetParameterValuesAsync(context, type, method)).ToArray();
return(await @delegate(instance, parameterValues));
},
methodGenericArgumentType);
}
else if (methodReturnTypeIsVoid)
{
ParameterInfo[] parameterInfos = method.GetParameters();
ParameterExpression instanceParameterExpression = Expression.Parameter(typeof(object), "instance");
ParameterExpression parametersParameterExpression = Expression.Parameter(typeof(object[]), "parameters");
MethodCallExpression methodCallExpression =
Expression.Call(
Expression.Convert(instanceParameterExpression, type),
method,
parameterInfos.Select((arg, index) => Expression.Convert(
Expression.ArrayIndex(parametersParameterExpression, Expression.Constant(index)),
arg.ParameterType)));
Action <object, object[]> @delegate = Expression.Lambda <Action <object, object[]> >(methodCallExpression, instanceParameterExpression, parametersParameterExpression).Compile();
route.RespondWithNoContent(
async context =>
{
object instance;
try
{
instance = container().GetInstance(type);
}
catch (Exception exception)
{
throw new ApplicationException(String.Format("Unable to resolve instance of type {0}.", type.FullName), exception);
}
if (instance == null)
{
throw new ApplicationException(String.Format("Unable to resolve instance of type {0}.", type.FullName));
}
var parameterValueRetriever = new ParameterValueRetriever(_parameterMappers);
object[] parameterValues = (await parameterValueRetriever.GetParameterValuesAsync(context, type, method)).ToArray();
@delegate(instance, parameterValues);
});
}
else
{
throw new ApplicationException(String.Format("The return type of {0}.{1} must implement {2} or be a {3} whose generic type argument implements {2}.", type.FullName, method.Name, typeof(IResponse).Name, typeof(Task <>)));
}
return(Task.Factory.Empty());
}
