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MassTransit - Cannot override the Consume method from RoutingSlipResponseProxy

I'm trying to set up a RoutingSlipResponseProxy that will prevent a response from being sent if there is no RequestId. I am trying to do this by overriding the Consume method in my RoutingSlipResponseProxy, like so:
public class MigrateResponseProxy : RoutingSlipResponseProxy<IMigrationRequested, IMigrationComplete>
{
public new async Task Consume(ConsumeContext<RoutingSlipCompleted> context)
{
var isRequest = context.Message.Variables.ContainsKey("RequestId");
if (!isRequest)
return;
var request = context.Message.GetVariable<IMigrationRequested>("Request");
var requestId = context.Message.GetVariable<Guid>("RequestId");
Uri responseAddress = null;
if (context.Message.Variables.ContainsKey("ResponseAddress"))
responseAddress = context.Message.GetVariable<Uri>("ResponseAddress");
if (responseAddress == null)
throw new ArgumentException($"The response address could not be found for the faulted routing slip: {context.Message.TrackingNumber}");
var endpoint = await context.GetResponseEndpoint<IMigrationComplete>(responseAddress, requestId).ConfigureAwait(false);
var response = await CreateResponseMessage(context, request);
await endpoint.Send(response).ConfigureAwait(false);
}
... remaining code ...
}
This is basically the same code as the original method, except with a check for the RequestId at the beginning. However, when debugging through the code, it seems as though this overridden method is never getting called, and instead the parent method is getting called. Is there something I might be missing here? Any help would be appreciated.

The methods aren't virtual, so you won't be able to override them. In this case, you'd be better of copying the proxy code into your own project instead of using the implementation that's included with MassTransit.
You're welcome to submit a PR to make those methods virtual.

I want to pass a int "index" parameter to an method dialog and also ask user to input a string for specific value he is going to search

I am writing a chat bot that can ask a user for name and a requirement to search job with.
Name and Requirement will be stored in UserData and PrivateConversationData.
I am trying to send the requirement as an index, 1-5, to a method dialog and to specify a requirement like salary amount and then call an appropriate api. But the bot keep giving an error when passing the parameter. How can I fix the error? Is it the way my method receives it or I use the wrong way to call it?
I'm trying to combine the requirement and job stuff into one single to prevent [Community Edit: To prevent what?]
private async Task MessageReceivedAsync(IDialogContext context, IAwaitable<object> result)
{
if (string.IsNullOrEmpty(name))//ask for the name
{
//code for get name
}
else
{
context.PrivateConversationData.TryGetValue<int>("Index", out int index);
if (!Enumerable.Range(1, 5).Contains(index))
{
var getRequirement =
FormDialog.FromForm(Requirement.BuildForm,
FormOptions.PromptInStart);
context.Call(getRequirement, AfterGetRequirementAsync);//able to get requirement index as int 1~5. next going to ask what specific value
}
else
{
await context.PostAsync($"{name}:{index}: {activity.Text}");//testing: it is able to print the name and the index user choose
context.Wait(MessageReceivedAsync);
}
}
I am using context.Call(getRequirement, AfterGetRequirementAsync) to try to get both requirement and then ask for the specific value in AfterGetRequirementAsync.
private async Task AfterGetRequirementAsync(IDialogContext context, IAwaitable<Requirement> result)
{
//Requirement requirementindex = null;
var requirementindex = await result;
context.PrivateConversationData.SetValue<int>("Index", requirementindex.Index);
await context.PostAsync($"Result：{JsonConvert.SerializeObject(requirementindex)}");//for testing index after user's input about index
var jobs = await GetJobDialog.LoadJob(requirementindex.Index);//Im trying to pass the .Index
//await context.PostAsync($"Job Search Result : {Environment.NewLine}{JsonConvert.SerializeObject(jobs)}");//trying to print the list of result to user
context.Wait(MessageReceivedAsync);
}
In AfterGetRequirementAsync, it is able to get the requirementindex and I can store it in PrivateConversationData in MessageReceivedAsync as Index. But when I try to pass the requirementindex.Index to GetJobDialog.JobModel.LoadJob it give me error of [Community Edit: What's the error?]
public class GetJobDialog
{
public Task StartAsync(IDialogContext context)
{
context.Wait(LoadJob(context.UserData));
return Task.CompletedTask;
}
public static async Task<List<JobModel>> LoadJob(IDialog context, IAwaitable<JobResultModel> result, int index)//depends on the job searching index, using different method to search.
{//it should return list of jobs to user.
string url = "";
if (index == 1)//posting type
{ //code like index == 4 }
else if (index == 2)//level
{ //code like index == 4 }
else if (index == 3)//full time or part time
{ //code like index == 4 }
else if (index == 4)//salary from
{ //ask for internal or external and change the end= to match value
url = $"https://data.cityofnewyork.us/resource/kpav-sd4t.json?salary_range_from=40000";
}//the only thing different is after .json? the index = specific value
else if (index == 5)//salary to
{ //code like index == 4 }
else//if not getting any valid option, throw error message and ask for index again
{
}
using (HttpResponseMessage response = await ApiHelper.ApiHelper.ApiClient.GetAsync(url))
{
if (response.IsSuccessStatusCode)
{
JobResultModel job = await response.Content.ReadAsAsync<JobResultModel>();
return job.Results;
}
else
{
throw new Exception(response.ReasonPhrase);
}
}
}
}
I am also trying to get the user to input the specific amount in the GetJobDialog. That way, the user doesn't have to enter anything to trigger the chat bot again.
I'm just posting the API caller incase I have some mistake because I learn all these by myself and do not have a clear understanding of how C# and api work.
public static class ApiHelper
{
public static HttpClient ApiClient { get; set; }
public static void InitializeClient()
{
ApiClient = new HttpClient();
ApiClient.DefaultRequestHeaders.Accept.Clear();
ApiClient.DefaultRequestHeaders.Accept.Add(new MediaTypeWithQualityHeaderValue("application/json"));
}
}
I expect the chat bot be able to pass the index to LoadJob and ask for specific value before or after the call of LoadJob. Then response a list of job with different field to the user.

I see a few issues with your code that might be causing this. If you can link me to all of your code, I might be able to help debug. In the meantime, here's some things might be causing the problem:
You're using BotBuilder V3 Code. If you're writing a new bot, you should really be using Botframework V4. Here's a State Management Sample Bot that can help you get started. You really should switch to V4, especially if this is a newer bot. If you run into issues in the future, you'll receive better support.
It looks like you're saving Index to PrivateConversationData, but when you pass it LoadJob(), you're using UserData instead.
I'm not sure that you can pass information when using context.Wait(). None of the V3 Samples do that. I don't use V3 much, so I can't tell for sure. What you should instead do, is use something like context.PrivateConversationData.TryGetValue<int>("Index", out int index); to load the index instead of passing it.
It also looks like you didn't post the error message. If you can post that and all of your code, I can help debug further (if the above doesn't work).

Portable Class Library HttpClient

For one of my projects I want to develop a library that can be used in different platforms (Desktop, Mobile, Surface, etc). Hence have opted Porable Class Library.
I am developing a class for calling different API calls' using HttpClient. I am stuck with how to call the method, response and work around. This is my code :-
public static async Task<JObject> ExecuteGet(string uri)
{
using (HttpClient client = new HttpClient())
{
// TODO - Send HTTP requests
HttpRequestMessage reqMsg = new HttpRequestMessage(HttpMethod.Get, uri);
reqMsg.Headers.Add(apiIdTag, apiIdKey);
reqMsg.Headers.Add(apiSecretTag, ApiSecret);
reqMsg.Headers.Add("Content-Type", "text/json");
reqMsg.Headers.Add("Accept", "application/json");
//response = await client.SendAsync(reqMsg);
//return response;
//if (response.IsSuccessStatusCode)
//{
string content = await response.Content.ReadAsStringAsync();
return (JObject.Parse(content));
//}
}
}
// Perform AGENT LOGIN Process
public static bool agentStatus() {
bool loginSuccess = false;
try
{
API_Utility.ExecuteGet("http://api.mintchat.com/agent/autoonline").Wait();
// ACCESS Response, JObject ???
}
catch
{
}
finally
{
}
Like ExecuteGet, I will also create for ExecutePost. My query is from ExecuteGet, if (1) I pass JObject on parsing when IsSuccessStatusCode only, then how can I know about any other errors or messages to inform the user. (2) If I pass response, then how do I assign it here
response = API_Utility.ExecuteGet("http://api.mintchat.com/agent/autoonline").Wait();
that is giving error.
What would be the best approach to handle this situation ? And I got to call multiple API's, so different API will have different result sets.
Also, can you confirm that designing this way and adding PCL reference I will be able to access in multiple projects.
UPDATE :-
As mentioned in below 2 answers I have updated my code. As mentioned in the provided link I am calling the from the other project. This is my code :-
Portable Class Library :-
private static HttpRequestMessage getGetRequest(string url)
{
HttpRequestMessage reqMsg = new HttpRequestMessage(HttpMethod.Get, url);
reqMsg.Headers.Add(apiIdTag, apiIdKey);
reqMsg.Headers.Add(apiSecretTag, ApiSecret);
reqMsg.Headers.Add("Content-Type", "text/json");
reqMsg.Headers.Add("Accept", "application/json");
return reqMsg;
}
// Perform AGENT LOGIN Process
public static async Task<bool> agentStatus() {
bool loginSuccess = false;
HttpClient client = null;
HttpRequestMessage request = null;
try
{
client = new HttpClient();
request = getGetRequest("http://api.mintchat.com/agent/autoonline");
response = await client.SendAsync(request).ConfigureAwait(false);
if (response.IsSuccessStatusCode)
{
string content = await response.Content.ReadAsStringAsync().ConfigureAwait(false);
JObject o = JObject.Parse(content);
bool stat = bool.Parse(o["status"].ToString());
///[MainAppDataObject sharedAppDataObject].authLogin.chatStatus = str;
o = null;
}
loginSuccess = true;
}
catch
{
}
finally
{
request = null;
client = null;
response = null;
}
return loginSuccess;
}
From the other WPF project, in a btn click event I am calling this as follows :-
private async void btnSignin_Click(object sender, RoutedEventArgs e)
{
/// Other code goes here
// ..........
agent = doLogin(emailid, encPswd);
if (agent != null)
{
//agent.OnlineStatus = getAgentStatus();
// Compile Error at this line
bool stat = await MintWinLib.Helpers.API_Utility.agentStatus();
...
I get these 4 errors :-
Error 1 Predefined type 'System.Runtime.CompilerServices.IAsyncStateMachine' is not defined or imported D:\...\MiveChat\CSC
Error 2 The type 'System.Threading.Tasks.Task`1<T0>' is defined in an assembly that is not referenced. You must add a reference to assembly 'System.Threading.Tasks, Version=1.5.11.0, Culture=neutral, PublicKeyToken=b03f5f7f89d50a3a'. D:\...\Login Form.xaml.cs 97 21
Error 3 Cannot find all types required by the 'async' modifier. Are you targeting the wrong framework version, or missing a reference to an assembly? D:\...\Login Form.xaml.cs 97 33
Error 4 Cannot find all types required by the 'async' modifier. Are you targeting the wrong framework version, or missing a reference to an assembly? D:\...\Login Form.xaml.cs 47 28
I tried adding System.Threading.Tasks from the PCL library only, that gave 7 different errors. Where am I going wrong ? What to do to make this working ?
Please guide me on this. Have spend lots of hours figuring the best to develop a library accessible to desktop app & Win Phone app.
Any help is highly appreciative. Thanks.

If you call an async api when making the http calls, you should also expose that async endpoint to the user, and not block the request using Task.Wait.
Also, when creating a third party library, it is recommanded to use ConfigureAwait(false) to avoid deadlocks when the calling code tries to access the Result property or the Wait method. You should also follow guidelines and mark any async method with Async, so the method should be called ExecuteStatusAsync
public static Task<bool> AgentStatusAsync()
{
bool loginSuccess = false;
try
{
// awaiting the task will unwrap it and return the JObject
var jObject = await API_Utility.ExecuteGet("http://api.mintchat.com/agent/autoonline").ConfigureAwait(false);
}
catch
{
}
}
And inside ExecuteGet:
response = await client.SendAsync(reqMsg).ConfigureAwait(false);
string content = await response.Content.ReadAsStringAsync().ConfigureAwait(false);
In case IsSuccessStatusCode is false, you may throw an exception to the calling code to show something went wrong. To do that, you can use the HttpResponseMessage.EnsureSuccessStatusCode which throws an exception if the status code != 200 OK.
Personally, if ExecuteGet is a public API method i would definitely not expose it as a JObject but a strongly typed type.

If you want the result of the task, you need to use the Result property:
var obj = API_Utility.ExecuteGet("http://api.mintchat.com/agent/autoonline").Result;
However, it's usually not a good idea to wait synchronously for an async method to complete, because it can cause deadlocks. The better approach is to await the method:
var obj = await API_Utility.ExecuteGet("http://api.mintchat.com/agent/autoonline");
Note that you need to make the calling method async as well:
public static async Task<bool> agentStatus()
Sync and async code don't play together very well, so async tends to propagate across the whole code base.

Response.Redirect issue with Asp.net async

I'm new to asp.net 4.5 async and am running into the following with calling response.redirect within an async method. The issue is that the response just "hangs" Has anyone else experienced similar issues with attempting an redirect with async? This code will work in a brand new project, but, does not work with a new page in our existing code. I made sure to gut out everything I could out of our web.config and removed our master page. Hitting a brick wall...any ideas? Thanks!
protected void Page_Load(object sender, EventArgs e)
{
RegisterAsyncTask(new PageAsyncTask(PageLoadAsync));
}
private async Task PageLoadAsync()
{
var data = await GetData();
if (data == HttpStatusCode.OK)
Response.Redirect("http://www.google.com");
}
private async Task<HttpStatusCode> GetData()
{
using (var client = new HttpClient())
{
var response = await client.GetAsync("https://www.google.com");
return response.StatusCode;
}
}

This code will work in a brand new project, but, does not work with a new page in our existing code.
I assume your existing site has already been upgraded to .NET 4.5.
The first thing to check is that httpRuntime.targetFramework is set to 4.5. This is not set by default when you upgrade.
Edit from comments:
Another thing to check (just in case) is that Page.Async is set to true.
In this case, the solution was to call Response.Redirect("http://www.google.com", false), which explicitly passes false for the endResponse parameter. The default value of true is only for backwards-compatibility reasons as described here.

The hack I used is:
I used a static dictionary as var d= new Dictionary<string, bool>(); in the class where my API calling method is written.
I put the code line client.timeout = new System.TimeSpan(0,0,60); for API sending the request.
When API is timed out, it throws the TaskTimeoutException, in the TaskTimeoutExceptioncatch block write code as d.Add("timeout", true);
Now, I created the custom action filter and applied the following code:
public class MyCustomActionFilter : ActionFilterAttribute
{
public override void OnActionExecuted(ActionExecutedContext filterContext)
{
if(MyApiClass.d.ContainsKey("timeout") && d["timeout"])
{
throw new Exception();
}
}
}
I applied the [MyCustomActionFilter ] on the action.
When action is executed and enter the custom filter it throws Exception by checking the dictionary entry.
If timeout would have occurred then dictionary entry will be true, so, on the basis of that, we check the entry and throws the exception. Now, we have Application_Error() in Global.asax.cs that catches the exception.
In the Application_Error() we have written the code for redirect to the required page.
NOTE: In step 4 you can create your custom exception to provide more precise detail for logging.

API Design for Timeouts: TimeoutException or boolean return with out parameter?

The scenario is RPC over message queues - since the underlying mechanism is asynchronous, clients should specify how long they want to wait for a response before timing out. As the client, which of these two code snippets would you rather use?
Most importantly: as a user of the GetResponseTo() method, why would you prefer one over the other? How does your choice make your code more extensible, more readable, more testable, etc?
try
{
IEvent response = _eventMgr.GetResponseTo(myRequest, myTimeSpan);
// I have my response!
}
catch(TimeoutException te)
{
// I didn't get a response to 'myRequest' within 'myTimeSpan'
}
OR
IEvent myResponse = null;
if (_eventMgr.GetResponseTo(myRequest, myTimeSpan, out myResponse)
{
// I got a response!
}
else
{
// I didn't get a response... :(
}
For your information, here's the current implementation of GetResponseTo():
public IEvent GetResponseTo(IEvent request, TimeSpan timeout)
{
if (null == request) { throw new ArgumentNullException("request"); }
// create an interceptor for the request
IEventInterceptor interceptor = new EventInterceptor(request, timeout);
// tell the dispatcher to watch for a response to this request
_eventDispatcher.AddInterceptor(interceptor);
// send the request
_queueManager.SendRequest(request);
// block this thread while we wait for a response. If the timeout elapses,
// this will throw a TimeoutException
interceptor.WaitForResponse();
// return the intercepted response
return interceptor.Response;
}

Neither first nor second, I would like to use the Task Parallel Library, which is the recommended way of doing all things asynchronous beginning with .NET 4.5:
Task<IEvent> task = _eventMgr.GetResponseToAsync(myRequest);
if (task.Wait(myTimeSpan))
{
// I got a response!
}
else
{
// I didn't get a response... :(
}

You could look to use AutoResetEvent class this will handle the plumbing for second one.
Try to avoid your first code snippet as exceptions are expensive

Personally i would prefer the exception Version. If i specify some timeout my opinion is that this IS a exception then if i couldn't get a result within the specified timespan. I don't think event based notification is the best decision here. The following Logic depends on the result so it doesn't make Sense for me.
But if you want to provide asynchronous Methods too, the Task thing is a good idea like stated by dtb

Exceptions are heavy and messy, each API method call should be wrapped by try/catch/finally to hanle custom exception. This approach is not developer-friendly so I do not like it.
Considering that GetResponse() call itself is synchronous for API consumer - it is pretty normal to return a value of operation, but I would suggest introducing something more abstract and informative rather than simple bool state, so you can return any state provided by the underlying messaging system, this could be a custom error code, message, or even object. So since this is API - put interface as well:
enum OperationStatus
{
Unknown,
Timeout,
Ok
}
// pretty simple, only message and status code
interface IOperationResult<T>
{
OperationStatus Status { get; }
string Message { get; }
T Item { get; }
}
class GetResponseResult : IOperationResult<IEvent>
{
...
}
class EventManager
{
public IOperationResult<IEvent> GetResponseTo(
IRequest request,
TimeSpan timeInterval)
{
GetResponseResult result;
// wait for async request
// ...
if (timeout)
{
result = new GetResponseResult
{
Status = OperationStatus.Timeout,
Message = underlyingMessagingLib.ErrorMessage
};
}
else
{
result = new GetResponseResult
{
Status = OperationStatus.Ok,
Item = response
};
}
return result;
}
}

I have elected to use the out parameter.
I wanted to mark someone else as the answer, but I am not able to do so. I attempted to implement the TPL-based approach, but was unable to do so, based on the question/answer that I linked in my comments.
I do not want to muddy my event model by introducing even more concepts, as #sll suggests.
And even though #dasheddot prefers the exception Version, #sll has a good point that someone trying to send a bunch of requests and get a bunch of responses in a loop might have to deal with a lot of exceptions.
// potentially 10 exceptions? meh... let's not go down this road.
for(int i=0;i<10;i++)
{
try
{
IEvent response = _eventMgr.GetResponseTo(myRequest, myTimeSpan);
// I have my response!
}
catch(TimeoutException te)
{
// I didn't get a response to 'myRequest' within 'myTimeSpan'
}
}