namespace AustinHarris.JsonRpc
{
using System;
using System.Collections;
using System.Collections.Generic;
using System.Linq;
using System.Reflection;
using Newtonsoft.Json;
using System.Threading.Tasks;
using System.Collections.Concurrent;
using Newtonsoft.Json.Linq;
using System.Threading;
public class Handler
{
#region Members
private static int _sessionHandlerMasterVersion = 1;
[ThreadStatic]
private static int _sessionHandlerLocalVersion = 0;
private static ConcurrentDictionary _sessionHandlersMaster;
[ThreadStatic]
private static Dictionary _sessionHandlersLocal;
private static volatile string _defaultSessionId;
#endregion
#region Constructors
static Handler()
{
//current = new Handler(Guid.NewGuid().ToString());
_defaultSessionId = Guid.NewGuid().ToString();
_sessionHandlersMaster = new ConcurrentDictionary();
_sessionHandlersMaster[_defaultSessionId] = new Handler(_defaultSessionId);
}
private Handler(string sessionId)
{
SessionId = sessionId;
this.MetaData = new SMD();
}
#endregion
#region Properties
///
/// Returns the SessionID of the default session
///
///
public static string DefaultSessionId() { return _defaultSessionId; }
///
/// Gets a specific session
///
/// The sessionId of the handler you want to retrieve.
///
public static Handler GetSessionHandler(string sessionId)
{
if (_sessionHandlerMasterVersion != _sessionHandlerLocalVersion)
{
_sessionHandlersLocal = new Dictionary(_sessionHandlersMaster);
_sessionHandlerLocalVersion = _sessionHandlerMasterVersion;
}
if (_sessionHandlersLocal.ContainsKey(sessionId))
{
return _sessionHandlersLocal[sessionId];
}
Interlocked.Increment(ref _sessionHandlerMasterVersion);
return _sessionHandlersMaster.GetOrAdd(sessionId, new Handler(sessionId));
}
///
/// gets the default session
///
/// The default Session Handler
public static Handler GetSessionHandler()
{
return GetSessionHandler(_defaultSessionId);
}
///
/// Removes and clears the Handler with the specific sessionID from the registry of Handlers
///
///
public static void DestroySession(string sessionId)
{
Handler h;
_sessionHandlersMaster.TryRemove(sessionId, out h);
Interlocked.Increment(ref _sessionHandlerMasterVersion);
h.MetaData.Services.Clear();
}
///
/// Removes and clears the current Handler from the registry of Handlers
///
public void Destroy()
{
DestroySession(SessionId);
}
///
/// Gets the default session handler
///
public static Handler DefaultHandler { get { return GetSessionHandler(_defaultSessionId); } }
///
/// The sessionID of this Handler
///
public string SessionId { get; private set; }
///
/// Provides access to a context specific to each JsonRpc method invocation.
/// Warning: Must be called from within the execution context of the jsonRpc Method to return the context
///
///
public static object RpcContext()
{
return __currentRpcContext;
}
[ThreadStatic]
static JsonRpcException __currentRpcException;
///
/// Allows you to set the exception used in in the JsonRpc response.
/// Warning: Must be called from the same thread as the jsonRpc method.
///
///
public static void RpcSetException(JsonRpcException exception)
{
__currentRpcException = exception;
}
public static JsonRpcException RpcGetAndRemoveRpcException()
{
var ex = __currentRpcException;
__currentRpcException = null ;
return ex;
}
private AustinHarris.JsonRpc.PreProcessHandler externalPreProcessingHandler;
private AustinHarris.JsonRpc.PostProcessHandler externalPostProcessingHandler;
private Func externalErrorHandler;
private Func parseErrorHandler;
#endregion
///
/// This metadata contains all the types and mappings of all the methods in this handler. Warning: Modifying this directly could cause your handler to no longer function.
///
public SMD MetaData { get; set; }
#region Public Methods
///
/// Allows you to register all the functions on a Pojo Type that have been attributed as [JsonRpcMethod] to the specified sessionId
///
/// The session to register against
/// The instance containing JsonRpcMethods to register
public static void RegisterInstance(string sessionID, object instance)
{
ServiceBinder.BindService(sessionID, instance);
}
///
/// Allows you to register any function, lambda, etc even when not attributed with JsonRpcMethod.
/// Requires you to specify all types and defaults
///
/// The method name that will map to the registered function
/// The parameter names and types that will be positionally bound to the function
/// Optional default values for parameters
/// A reference to the Function
public void RegisterFuction(string methodName, Dictionary parameterNameTypeMapping, Dictionary parameterNameDefaultValueMapping, Delegate implementation)
{
MetaData.AddService(methodName, parameterNameTypeMapping, parameterNameDefaultValueMapping, implementation);
}
public void UnRegisterFunction(string methodName)
{
MetaData.Services.Remove(methodName);
}
public void SetPreProcessHandler(AustinHarris.JsonRpc.PreProcessHandler handler)
{
externalPreProcessingHandler = handler;
}
public void SetPostProcessHandler(AustinHarris.JsonRpc.PostProcessHandler handler)
{
externalPostProcessingHandler = handler;
}
///
/// Invokes a method to handle a JsonRpc request.
///
/// JsonRpc Request to be processed
/// Optional context that will be available from within the jsonRpcMethod.
///
public JsonResponse Handle(JsonRequest Rpc, Object RpcContext = null)
{
AddRpcContext(RpcContext);
var preProcessingException = PreProcess(Rpc, RpcContext);
if (preProcessingException != null)
{
JsonResponse response = new JsonResponse()
{
Error = preProcessingException,
Id = Rpc.Id
};
//callback is called - if it is empty then nothing will be done
//return response always- if callback is empty or not
return PostProcess(Rpc, response, RpcContext);
}
SMDService metadata = null;
Delegate handle = null;
var haveMetadata = this.MetaData.Services.TryGetValue(Rpc.Method, out metadata);
if (haveMetadata)
{
handle = metadata.dele;
}
if (haveMetadata == false || metadata == null)
{
JsonResponse response = new JsonResponse()
{
Result = null,
Error = new JsonRpcException(-32601, "Method not found", "The method does not exist / is not available."),
Id = Rpc.Id
};
return PostProcess(Rpc, response, RpcContext);
}
bool isJObject = Rpc.Params is Newtonsoft.Json.Linq.JObject;
bool isJArray = Rpc.Params is Newtonsoft.Json.Linq.JArray;
object[] parameters = null;
bool expectsRefException = false;
var metaDataParamCount = metadata.parameters.Count(x => x != null);
var getCount = Rpc.Params as ICollection;
var loopCt = 0;
if (getCount != null)
{
loopCt = getCount.Count;
}
var paramCount = loopCt;
if (paramCount == metaDataParamCount - 1 && metadata.parameters[metaDataParamCount - 1].ObjectType.Name.Contains(typeof(JsonRpcException).Name))
{
paramCount++;
expectsRefException = true;
}
parameters = new object[paramCount];
if (isJArray)
{
var jarr = ((Newtonsoft.Json.Linq.JArray)Rpc.Params);
//var loopCt = jarr.Count;
//var pCount = loopCt;
//if (pCount == metaDataParamCount - 1 && metadata.parameters[metaDataParamCount].GetType() == typeof(JsonRpcException))
// pCount++;
//parameters = new object[pCount];
for (int i = 0; i < loopCt; i++)
{
parameters[i] = CleanUpParameter(jarr[i], metadata.parameters[i]);
}
}
else if (isJObject)
{
var jo = Rpc.Params as Newtonsoft.Json.Linq.JObject;
//var loopCt = jo.Count;
//var pCount = loopCt;
//if (pCount == metaDataParamCount - 1 && metadata.parameters[metaDataParamCount].GetType() == typeof(JsonRpcException))
// pCount++;
//parameters = new object[pCount];
var asDict = jo as IDictionary;
for (int i = 0; i < loopCt && i < metadata.parameters.Length; i++)
{
if (asDict.ContainsKey(metadata.parameters[i].Name) == false)
{
JsonResponse response = new JsonResponse()
{
Error = ProcessException(Rpc,
new JsonRpcException(-32602,
"Invalid params",
string.Format("Named parameter '{0}' was not present.",
metadata.parameters[i].Name)
)),
Id = Rpc.Id
};
return PostProcess(Rpc, response, RpcContext);
}
parameters[i] = CleanUpParameter(jo[metadata.parameters[i].Name], metadata.parameters[i]);
}
}
// Optional Parameter support
// check if we still miss parameters compared to metadata which may include optional parameters.
// if the rpc-call didn't supply a value for an optional parameter, we should be assinging the default value of it.
if (parameters.Length < metaDataParamCount && metadata.defaultValues.Length > 0) // rpc call didn't set values for all optional parameters, so we need to assign the default values for them.
{
var suppliedParamsCount = parameters.Length; // the index we should start storing default values of optional parameters.
var missingParamsCount = metaDataParamCount - parameters.Length; // the amount of optional parameters without a value set by rpc-call.
Array.Resize(ref parameters, parameters.Length + missingParamsCount); // resize the array to include all optional parameters.
for (int paramIndex = parameters.Length - 1, defaultIndex = metadata.defaultValues.Length - 1; // fill missing parameters from the back
paramIndex >= suppliedParamsCount && defaultIndex >= 0; // to don't overwrite supplied ones.
paramIndex--, defaultIndex--)
{
parameters[paramIndex] = metadata.defaultValues[defaultIndex].Value;
}
if (missingParamsCount > metadata.defaultValues.Length)
{
JsonResponse response = new JsonResponse
{
Error = ProcessException(Rpc,
new JsonRpcException(-32602,
"Invalid params",
string.Format(
"Number of default parameters {0} not sufficient to fill all missing parameters {1}",
metadata.defaultValues.Length, missingParamsCount)
)),
Id = Rpc.Id
};
return PostProcess(Rpc, response, RpcContext);
}
}
if (parameters.Length != metaDataParamCount)
{
JsonResponse response = new JsonResponse()
{
Error = ProcessException(Rpc,
new JsonRpcException(-32602,
"Invalid params",
string.Format("Expecting {0} parameters, and received {1}",
metadata.parameters.Length,
parameters.Length)
)),
Id = Rpc.Id
};
return PostProcess(Rpc, response, RpcContext);
}
try
{
var results = handle.DynamicInvoke(parameters);
var last = parameters.LastOrDefault();
var contextException = RpcGetAndRemoveRpcException();
if (contextException != null)
{
JsonResponse response = new JsonResponse() { Error = ProcessException(Rpc, contextException), Id = Rpc.Id };
return PostProcess(Rpc, response, RpcContext);
}
if (expectsRefException && last != null && last is JsonRpcException)
{
JsonResponse response = new JsonResponse() { Error = ProcessException(Rpc, last as JsonRpcException), Id = Rpc.Id };
return PostProcess(Rpc, response, RpcContext);
}
return PostProcess(Rpc, new JsonResponse() { Result = results }, RpcContext);
}
catch (Exception ex)
{
JsonResponse response;
if (ex is TargetParameterCountException)
{
response = new JsonResponse() { Error = ProcessException(Rpc, new JsonRpcException(-32602, "Invalid params", ex)) };
return PostProcess(Rpc, response, RpcContext);
}
// We really dont care about the TargetInvocationException, just pass on the inner exception
if (ex is JsonRpcException)
{
response = new JsonResponse() { Error = ProcessException(Rpc, ex as JsonRpcException) };
return PostProcess(Rpc, response, RpcContext);
}
if (ex.InnerException != null && ex.InnerException is JsonRpcException)
{
response = new JsonResponse() { Error = ProcessException(Rpc, ex.InnerException as JsonRpcException) };
return PostProcess(Rpc, response, RpcContext);
}
else if (ex.InnerException != null)
{
response = new JsonResponse() { Error = ProcessException(Rpc, new JsonRpcException(-32603, "Internal Error", ex.InnerException)) };
return PostProcess(Rpc, response, RpcContext);
}
response = new JsonResponse() { Error = ProcessException(Rpc, new JsonRpcException(-32603, "Internal Error", ex)) };
return PostProcess(Rpc, response, RpcContext);
}
finally
{
RemoveRpcContext();
}
}
#endregion
[ThreadStatic]
static object __currentRpcContext;
private void AddRpcContext(object RpcContext)
{
__currentRpcContext = RpcContext;
}
private void RemoveRpcContext()
{
__currentRpcContext = null;
}
private JsonRpcException ProcessException(JsonRequest req, JsonRpcException ex)
{
if (externalErrorHandler != null)
return externalErrorHandler(req, ex);
return ex;
}
internal JsonRpcException ProcessParseException(string req, JsonRpcException ex)
{
if (parseErrorHandler != null)
return parseErrorHandler(req, ex);
return ex;
}
internal void SetErrorHandler(Func handler)
{
externalErrorHandler = handler;
}
internal void SetParseErrorHandler(Func handler)
{
parseErrorHandler = handler;
}
private object CleanUpParameter(object p, SMDAdditionalParameters metaData)
{
var bob = p as JValue;
//if (bob != null && (bob.Value == null || bob.Value.GetType() == metaData.ObjectType))
if (bob != null && (bob.Value == null))
{
return bob.Value;
}
if (bob != null)
{
// Avoid calling DeserializeObject on types that JValue has an explicit converter for
// try to optimize for the most common types
if (metaData.ObjectType == typeof(string)) return (string)bob;
if (metaData.ObjectType == typeof(int)) return (int)bob;
if (metaData.ObjectType == typeof(double)) return (double)bob;
if (metaData.ObjectType == typeof(float)) return (float)bob;
//if (metaData.ObjectType == typeof(long)) return (long)bob;
//if (metaData.ObjectType == typeof(uint)) return (uint)bob;
//if (metaData.ObjectType == typeof(ulong)) return (ulong)bob;
//if (metaData.ObjectType == typeof(byte[])) return (byte[])bob;
//if (metaData.ObjectType == typeof(Guid)) return (Guid)bob;
if (metaData.ObjectType == typeof(decimal)) return (decimal)bob;
//if (metaData.ObjectType == typeof(TimeSpan)) return (TimeSpan)bob;
//if (metaData.ObjectType == typeof(short)) return (short)bob;
//if (metaData.ObjectType == typeof(ushort)) return (ushort)bob;
//if (metaData.ObjectType == typeof(char)) return (char)bob;
//if (metaData.ObjectType == typeof(DateTime)) return (DateTime)bob;
//if (metaData.ObjectType == typeof(bool)) return (bool)bob;
//if (metaData.ObjectType == typeof(DateTimeOffset)) return (DateTimeOffset)bob;
if (metaData.ObjectType.IsAssignableFrom(typeof(JValue)))
return bob;
try
{
return bob.ToObject(metaData.ObjectType);
}
catch (Exception ex)
{
// no need to throw here, they will
// get an invalid cast exception right after this.
}
}
else
{
try
{
if (p is string)
return JsonConvert.DeserializeObject((string)p, metaData.ObjectType);
return JsonConvert.DeserializeObject(p.ToString(), metaData.ObjectType);
}
catch (Exception ex)
{
// no need to throw here, they will
// get an invalid cast exception right after this.
}
}
return p;
}
private JsonRpcException PreProcess(JsonRequest request, object context)
{
if (externalPreProcessingHandler == null)
return null;
return externalPreProcessingHandler(request, context);
}
private JsonResponse PostProcess(JsonRequest request, JsonResponse response, object context)
{
if (externalPostProcessingHandler != null)
{
try
{
JsonRpcException exception = externalPostProcessingHandler(request, response, context);
if (exception != null)
{
response = new JsonResponse() { Error = exception };
}
}
catch (Exception ex)
{
response = new JsonResponse() { Error = ProcessException(request, new JsonRpcException(-32603, "Internal Error", ex)) };
}
}
return response;
}
}
}