public void TestRemoteMethodCallSerialization()
{
var call = new RemoteMethodCall();
call.ComponentName = "component";
call.CallId = Guid.NewGuid();
call.MethodName = "sampleMethod";
call.Parameters = new List<object> { 1, 2, 3 };
var xml = call.Serialize();
var roundtrip = new RemoteMethodCall();
Assert.IsTrue(roundtrip.Validate(xml));
roundtrip.Deserialize(xml);
Assert.IsNotNull(roundtrip);
Assert.AreEqual<Guid>(call.CallId, roundtrip.CallId);
Assert.AreEqual<string>(call.ComponentName, roundtrip.ComponentName);
Assert.AreEqual<string>(call.MethodName, roundtrip.MethodName);
Assert.AreEqual<int>(call.Parameters.Count(), roundtrip.Parameters.Count());
int count = call.Parameters.Count();
for (int i = 0; i < count; i++)
{
Assert.AreEqual<int>((int)call.Parameters.Skip(i).First(), (int)roundtrip.Parameters.Skip(i).First());
}
}
/// <summary>
/// Processes an incoming RemoteMethodResponse
/// </summary>
/// <param name="response">The RemoteMethodResponse that is to be processed</param>
protected virtual void processRemoteMethodResponse(RemoteMethodResponse response)
{
//get the RemoteMethodCall that triggered the response from the cache
RemoteMethodCall call = unrepliedCalls.ContainsKey(response.CallId) ? unrepliedCalls[response.CallId] : null;
//response is only processed, when the associated method call could be found
if (call != null)
{
//stop the connection from timing out as we just received a message
timeoutTimer.Stop();
//if call was synchronous => put the response value in the value cache and release wait handle
if (synchronousCalls_WaitHandles.ContainsKey(call.CallId))
{
synchonousCalls_ValueCache.Add(call.CallId, response.ResponseValue);
synchronousCalls_WaitHandles[call.CallId].Set();
}
//remove call from unreplied calls
unrepliedCalls.Remove(response.CallId);
//decrease the number of repsonses expected from the target client (connection will not time out when no responses are expected
if (call.ResponseExpected)
{
this.expectedResponseCount--;
}
//if there are still call taht are unreplied, restart the timeout-timer
if (unrepliedCalls.Any())
{
timeoutTimer.Start();
}
}
}
/// <summary>
/// Send a message to the target client
/// </summary>
/// <param name="msg">The message to process and send</param>
protected virtual void sendMessage(RpcMessage msg)
{
//if message is a RemoteMethodCall, it will be cached to be able to process response messages
if (msg is RemoteMethodCall)
{
RemoteMethodCall call = msg as RemoteMethodCall;
if (call.ResponseExpected)
{
unrepliedCalls.Add(call.CallId, call);
expectedResponseCount++;
timeoutTimer.Start();
}
}
//process the message using the MessageProcessor and pass the result to the ConnectionManager to send
try
{
this.WtlpClient.Send(msg.Serialize().ToString().GetBytesUTF8());
}
catch (WtlpException ex)
{
if (ex.Error == Result.Timeout)
{
throw new TimeoutException();
}
else
{
throw new RemoteErrorException();
}
}
}
public void TestRemoteMethodCallSerialization_MissingComponentNameElement()
{
var call = new RemoteMethodCall();
call.ComponentName = "component";
call.CallId = Guid.NewGuid();
call.MethodName = "sampleMethod";
call.Parameters = new List<object> { 1, 2, 3 };
var xml = call.Serialize();
xml.Element(XName.Get("ComponentName", xml.Name.NamespaceName)).Remove();
var roundtrip = new RemoteMethodCall();
Assert.IsFalse(roundtrip.Validate(xml));
}
protected object invokeRemoteMethod(string component, string name, object[] args, bool responseExpected)
{
var call = new RemoteMethodCall()
{
ComponentName = component, MethodName = name, Parameters = args.ToList <object>(), ResponseExpected = responseExpected
};
//send the RemoteMethodCall
sendMessage(call);
//if a response is expected, wait for the recipient to send a response
if (responseExpected)
{
//wait for the response using a EventWaitHandle
if (!synchronousCalls_WaitHandles.ContainsKey(call.CallId))
{
synchronousCalls_WaitHandles.Add(call.CallId, new EventWaitHandle(false, EventResetMode.ManualReset));
}
synchronousCalls_WaitHandles[call.CallId].WaitOne();
//get the returned value from the cache
object value = synchonousCalls_ValueCache[call.CallId];
//remove the value from value cache
synchonousCalls_ValueCache.Remove(call.CallId);
if (value is TimeoutException)
{
throw (value as TimeoutException);
}
else if (value is RemoteError)
{
throw new RemoteErrorException(value as RemoteError);
}
else
{
return(value);
}
}
else
{
return(null);
}
}
/// <summary>
/// Processes an incoming RemoteMethodCall
/// </summary>
/// <param name="call">The RemoteMethodCall that is to be processed</param>
/// <param name="component">The component that will handle the call</param>
protected virtual void processRemoteMethodCall(RemoteMethodCall call, IComponent component)
{
//get the call's result
CallResult callResult = getCallResult(call, component);
if (callResult is ErrorResult)
{
//result was error => send RemoteError
sendMessage(
new RemoteError((callResult as ErrorResult).ErrorCode)
{
CallId = call.CallId,
ComponentName = call.ComponentName
}
);
}
else if (callResult is ResponseResult)
{
//result was a response => send RemoteMethodResponse
RemoteMethodResponse response = new RemoteMethodResponse();
response.CallId = call.CallId;
response.ComponentName = call.ComponentName;
response.ResponseValue = (callResult as ResponseResult).ResponseValue;
sendMessage(response);
}
else if (callResult is VoidResult)
{
//result was VoidResult => do nothing
}
else
{
//should not happen, ResponseResult, ErrorResult and VoidResult are the only known subclasses of CallResult the
logger.Error("ProcessMessage() encountered an unknown type of CallResult");
}
//If a post-processing action has been specified in the call, invoke it now
if (callResult.PostProcessingAction != null)
{
callResult.PostProcessingAction.Invoke();
}
}
/// <summary>
/// Tries to retrive a <see cref="CallResult"/> from the specified component for the speicified RemoteMethodCall using Reflection
/// </summary>
/// <param name="call">The RemoteMethodCall that needs to be answered</param>
/// <param name="component">The component the RemoteMethodCall targeted</param>
/// <returns>Returns the <see cref="CallResult"/> for the specified RemoteMethodCall</returns>
protected virtual CallResult getCallResult(RemoteMethodCall call, IComponent component)
{
//search the component for a method taht can handle the call
Dictionary <string, MethodInfo> callHandlers = new Dictionary <string, MethodInfo>();
foreach (MethodInfo mi in component.GetType().GetMethods(BindingFlags.NonPublic | BindingFlags.Instance | BindingFlags.Public))
{
object[] attributes = mi.GetCustomAttributes(typeof(MethodCallHandlerAttribute), true);
foreach (MethodCallHandlerAttribute attr in attributes)
{
if (!callHandlers.ContainsKey(attr.MethodName))
{
callHandlers.Add(attr.MethodName, mi);
}
}
}
if (callHandlers.ContainsKey(call.MethodName))
{
var attributes = callHandlers[call.MethodName].GetCustomAttributes(typeof(TrustLevelAttribute), true);
//get the trust level from the method's TrustLevel attribute
TrustLevelAttribute trustLevel;
if (attributes.Any())
{
trustLevel = (TrustLevelAttribute)attributes.First();
}
else
{
//if no attribute could be found, fall back to the default (highest possible trustlevel)
trustLevel = TrustLevelAttribute.MAX;
}
//check if the sender is authorized to make that method call
if (trustLevel.RequiredTrustLevel > this.TrustLevel)
{
return(new ErrorResult(RemoteErrorCode.NotAuthorizedError));
}
else
{
//invoke the call handler method and return it's result
try
{
return((CallResult)callHandlers[call.MethodName].Invoke(component, call.Parameters.ToArray <object>()));
}
catch (Exception e)
{
if (e.GetType() == typeof(ArgumentException) || e.GetType() == typeof(TargetParameterCountException))
{
return(new ErrorResult(RemoteErrorCode.InvalidParametersError));
}
else
{
throw;
}
}
}
}
//Invoked method could not be found => return ErrorResult
else
{
return(new ErrorResult(RemoteErrorCode.MethodNotFoundError));
}
}
/// <summary>
/// Processes an incoming message (using the MessageProcessor for deserialization)
/// </summary>
/// <param name="message">The message to be processed</param>
private void processMessage(ParsingResult message)
{
//parse the message
XElement xmlMessage;
RpcMessage msg = null;
var body = message.Payload.ToStringUTF8();
try
{
//try to parse it as XML
xmlMessage = XElement.Parse(body);
switch (xmlMessage.Name.LocalName.ToLower())
{
case "remotemethodcall":
msg = new RemoteMethodCall();
break;
case "remotemethodresponse":
msg = new RemoteMethodResponse();
break;
case "remoteerror":
msg = new RemoteError();
break;
}
if (!msg.Validate(xmlMessage))
{
logger.Error("Message from {0} could not be validated", this.Target);
var error = new RemoteError(RemoteErrorCode.InvalidXmlError);
sendMessage(error);
return;
}
msg.Deserialize(xmlMessage);
}
//Catch XmlException and wrap it into a format exception (makes catching errors in the caller easier)
catch (XmlException)
{
logger.Error("Could not parse message received from {0}", this.Target);
RemoteError error = new RemoteError(RemoteErrorCode.InvalidXmlError);
sendMessage(error);
return;
}
//encryption is mandatory if TrustLevel is 2 or higher
//if message was not encrypted it will result in a RemoteError and the connection will be reset
if (this.TrustLevel >= 2 && !message.WasEncrypted && !(msg is RemoteMethodCall && (msg as RemoteMethodCall).MethodName == CoreMethods.SendResetNotice))
{
RemoteError error = new RemoteError(RemoteErrorCode.EncryptionError);
if (msg.CallId != Guid.Empty)
{
error.CallId = msg.CallId;
}
error.ComponentName = "Authentication";
//The RemoteError will not be encrypted
WtlpClient.EncryptMessages = false;
sendMessage(error);
ResetConnection();
return;
}
if (msg is RemoteMethodCall)
{
//get the component responsible for handling the message
string componentName = (msg as RpcMessage).ComponentName;
var component = GetServerComponent(componentName);
if (component == null)
{
//no component to handle the request was found => send a RemoteError as response and return
RemoteError error = new RemoteError(RemoteErrorCode.ComponentNotFoundError);
error.CallId = (msg as RemoteMethodCall).CallId;
sendMessage(error);
return;
}
var processingTask = new Task(delegate
{
processRemoteMethodCall(msg as RemoteMethodCall, component);
});
processingTask.Start();
var heartBeatTask = new Task(delegate
{
var coreComponent = new CoreClientComponent();
coreComponent.ClientConnection = this;
while (!processingTask.IsCompleted)
{
Thread.Sleep(25000);
if (!processingTask.IsCompleted)
{
coreComponent.HeartbeatAsync();
}
}
});
heartBeatTask.Start();
}
else if (msg is RemoteMethodResponse)
{
processRemoteMethodResponse(msg as RemoteMethodResponse);
}
else if (msg is RemoteError)
{
processRemoteError(msg as RemoteError);
}
else
{
logger.Error("ProcessMessage() encoutered an unknown type of Message");
sendMessage(new RemoteError(RemoteErrorCode.UnknownMessage));
}
}
/// <summary>
/// Processes an incoming message (using the MessageProcessor for deserialization)
/// </summary>
/// <param name="message">The message to be processed</param>
private void processMessage(ParsingResult message)
{
//parse the message
XElement xmlMessage;
RpcMessage msg = null;
var body = message.Payload.ToStringUTF8();
try
{
//try to parse it as XML
xmlMessage = XElement.Parse(body);
switch (xmlMessage.Name.LocalName.ToLower())
{
case "remotemethodcall":
msg = new RemoteMethodCall();
break;
case "remotemethodresponse":
msg = new RemoteMethodResponse();
break;
case "remoteerror":
msg = new RemoteError();
break;
}
if (!msg.Validate(xmlMessage))
{
logger.Error("Message from {0} could not be validated", this.Target);
var error = new RemoteError(RemoteErrorCode.InvalidXmlError);
sendMessage(error);
return;
}
msg.Deserialize(xmlMessage);
}
//Catch XmlException and wrap it into a format exception (makes catching errors in the caller easier)
catch (XmlException)
{
logger.Error("Could not parse message received from {0}", this.Target);
RemoteError error = new RemoteError(RemoteErrorCode.InvalidXmlError);
sendMessage(error);
return;
}
//encryption is mandatory if TrustLevel is 2 or higher
//if message was not encrypted it will result in a RemoteError and the connection will be reset
if (this.TrustLevel >= 2 && !message.WasEncrypted && !(msg is RemoteMethodCall && (msg as RemoteMethodCall).MethodName == CoreMethods.SendResetNotice))
{
RemoteError error = new RemoteError(RemoteErrorCode.EncryptionError);
if (msg.CallId != Guid.Empty)
error.CallId = msg.CallId;
error.ComponentName = "Authentication";
//The RemoteError will not be encrypted
WtlpClient.EncryptMessages = false;
sendMessage(error);
ResetConnection();
return;
}
if (msg is RemoteMethodCall)
{
//get the component responsible for handling the message
string componentName = (msg as RpcMessage).ComponentName;
var component = GetServerComponent(componentName);
if (component == null)
{
//no component to handle the request was found => send a RemoteError as response and return
RemoteError error = new RemoteError(RemoteErrorCode.ComponentNotFoundError);
error.CallId = (msg as RemoteMethodCall).CallId;
sendMessage(error);
return;
}
var processingTask = new Task(delegate
{
processRemoteMethodCall(msg as RemoteMethodCall, component);
});
processingTask.Start();
var heartBeatTask = new Task(delegate
{
var coreComponent = new CoreClientComponent();
coreComponent.ClientConnection = this;
while (!processingTask.IsCompleted)
{
Thread.Sleep(25000);
if (!processingTask.IsCompleted)
coreComponent.HeartbeatAsync();
}
});
heartBeatTask.Start();
}
else if (msg is RemoteMethodResponse)
{
processRemoteMethodResponse(msg as RemoteMethodResponse);
}
else if (msg is RemoteError)
{
processRemoteError(msg as RemoteError);
}
else
{
logger.Error("ProcessMessage() encoutered an unknown type of Message");
sendMessage(new RemoteError(RemoteErrorCode.UnknownMessage));
}
}
/// <summary>
/// Processes an incoming RemoteMethodCall
/// </summary>
/// <param name="call">The RemoteMethodCall that is to be processed</param>
/// <param name="component">The component that will handle the call</param>
protected virtual void processRemoteMethodCall(RemoteMethodCall call, IComponent component)
{
//get the call's result
CallResult callResult = getCallResult(call, component);
if (callResult is ErrorResult)
{
//result was error => send RemoteError
sendMessage(
new RemoteError((callResult as ErrorResult).ErrorCode)
{
CallId = call.CallId,
ComponentName = call.ComponentName
}
);
}
else if (callResult is ResponseResult)
{
//result was a response => send RemoteMethodResponse
RemoteMethodResponse response = new RemoteMethodResponse();
response.CallId = call.CallId;
response.ComponentName = call.ComponentName;
response.ResponseValue = (callResult as ResponseResult).ResponseValue;
sendMessage(response);
}
else if (callResult is VoidResult)
{
//result was VoidResult => do nothing
}
else
{
//should not happen, ResponseResult, ErrorResult and VoidResult are the only known subclasses of CallResult the
logger.Error("ProcessMessage() encountered an unknown type of CallResult");
}
//If a post-processing action has been specified in the call, invoke it now
if (callResult.PostProcessingAction != null)
{
callResult.PostProcessingAction.Invoke();
}
}
protected object invokeRemoteMethod(string component, string name, object[] args, bool responseExpected)
{
var call = new RemoteMethodCall() { ComponentName = component, MethodName = name, Parameters = args.ToList<object>(), ResponseExpected = responseExpected };
//send the RemoteMethodCall
sendMessage(call);
//if a response is expected, wait for the recipient to send a response
if (responseExpected)
{
//wait for the response using a EventWaitHandle
if (!synchronousCalls_WaitHandles.ContainsKey(call.CallId))
synchronousCalls_WaitHandles.Add(call.CallId, new EventWaitHandle(false, EventResetMode.ManualReset));
synchronousCalls_WaitHandles[call.CallId].WaitOne();
//get the returned value from the cache
object value = synchonousCalls_ValueCache[call.CallId];
//remove the value from value cache
synchonousCalls_ValueCache.Remove(call.CallId);
if (value is TimeoutException)
{
throw (value as TimeoutException);
}
else if (value is RemoteError)
{
throw new RemoteErrorException(value as RemoteError);
}
else
{
return value;
}
}
else
{
return null;
}
}
/// <summary>
/// Tries to retrive a <see cref="CallResult"/> from the specified component for the speicified RemoteMethodCall using Reflection
/// </summary>
/// <param name="call">The RemoteMethodCall that needs to be answered</param>
/// <param name="component">The component the RemoteMethodCall targeted</param>
/// <returns>Returns the <see cref="CallResult"/> for the specified RemoteMethodCall</returns>
protected virtual CallResult getCallResult(RemoteMethodCall call, IComponent component)
{
//search the component for a method taht can handle the call
Dictionary<string, MethodInfo> callHandlers = new Dictionary<string, MethodInfo>();
foreach (MethodInfo mi in component.GetType().GetMethods(BindingFlags.NonPublic | BindingFlags.Instance | BindingFlags.Public))
{
object[] attributes = mi.GetCustomAttributes(typeof(MethodCallHandlerAttribute), true);
foreach (MethodCallHandlerAttribute attr in attributes)
{
if (!callHandlers.ContainsKey(attr.MethodName))
{
callHandlers.Add(attr.MethodName, mi);
}
}
}
if (callHandlers.ContainsKey(call.MethodName))
{
var attributes = callHandlers[call.MethodName].GetCustomAttributes(typeof(TrustLevelAttribute), true);
//get the trust level from the method's TrustLevel attribute
TrustLevelAttribute trustLevel;
if (attributes.Any())
trustLevel = (TrustLevelAttribute)attributes.First();
else
//if no attribute could be found, fall back to the default (highest possible trustlevel)
trustLevel = TrustLevelAttribute.MAX;
//check if the sender is authorized to make that method call
if (trustLevel.RequiredTrustLevel > this.TrustLevel)
{
return new ErrorResult(RemoteErrorCode.NotAuthorizedError);
}
else
{
//invoke the call handler method and return it's result
try
{
return (CallResult)callHandlers[call.MethodName].Invoke(component, call.Parameters.ToArray<object>());
}
catch (Exception e)
{
if (e.GetType() == typeof(ArgumentException) || e.GetType() == typeof(TargetParameterCountException))
{
return new ErrorResult(RemoteErrorCode.InvalidParametersError);
}
else { throw; }
}
}
}
//Invoked method could not be found => return ErrorResult
else
{
return new ErrorResult(RemoteErrorCode.MethodNotFoundError);
}
}
public void TestRemoteMethodCallSerialization_NoParameters()
{
var call = new RemoteMethodCall();
call.ComponentName = "component";
call.CallId = Guid.NewGuid();
call.MethodName = "sampleMethod";
var xml = call.Serialize();
var roundtrip = new RemoteMethodCall();
Assert.IsTrue(roundtrip.Validate(xml));
roundtrip.Deserialize(xml);
Assert.IsNotNull(roundtrip);
Assert.AreEqual<Guid>(call.CallId, roundtrip.CallId);
Assert.AreEqual<string>(call.ComponentName, roundtrip.ComponentName);
Assert.AreEqual<string>(call.MethodName, roundtrip.MethodName);
}
