We have a IIS 8 web server on which Web API is deployed. We have a front end application written in extJS. When the application accessed, it makes sever API calls to the server and many of these calls return success except one specific API call. Chrome says request status as cancelled (ERR_CONNECTION_RESET), and I am not able to figure out how to troubleshoot and fix this error. I have checked many places online but I could not get much help.
Please help.
Are you using Entity Framework Core? If so, you may have an object graph loop in your many-to-many relationships as EFCore does not support lazy loading at this time.
If so, you can configure your serializer to not follow graph loops.
In your Startup.cs file, replace the services.AddMvc() line with this:
services.AddMvc()
.AddJsonOptions(options => options.SerializerSettings.ReferenceLoopHandling = Newtonsoft.Json.ReferenceLoopHandling.Ignore);
Related
Using ASP.NET Core with the Identity framework.
I have a project running on Azure, with a SQL Server database, a web site and an API.
Suddenly, today when trying to login to the system (from the app that calls the API), it is stuck for around 15 seconds and then I get an error http 500.
I try to run the API function that authenticate the user from the local env. and was able to reproduce the bug.
The first line of the function is :
var user = await _userManager.FindByEmailAsync(model.Username);
This is the line the program is stuck till getting error message 500.
I don't even know how to approach this, I try to add a line that retrieves one of the user details, just to make sure the API can still talk to the database and it works fine.
How can check what is wrong with it? If I had the implementation of this function, maybe I can debug it.
Any suggestions?
I have a .net core service that needs to send a request via nservicebus.
I resolve IMessageSession with DI and send a request like this:
var response = await messageSession.Request<CreateDeviceResponse>(request);
In the logs I see that another service received this request and send a reply:
The problem that I never receive a response.
Client receive such errors:
I know that such an issue can occur if the client and server endpoint names are same, but I checked and I use different names
asp net mvc 4.7.2
First of all, the message isn't lost, but in the error queue.
I suggest to follow the tutorial to understand how NServiceBus works and what you need to have in place where. The tutorials start here but an entire learning path starts here and it explains broader, including about general concepts and architecture.
Like #tchelidze mentions, you need to have an implementation of the IHandleMessages<CreateDeviceReponse> interface, like is outlined here in the tutorial. Also, it doesn't matter to which endpoint you send it to. EndpointA can send to both EndpointB and EndpointA. What you cannot do is have two endpoints with the same name. It's like having two computers with the same name called MachineA and then from MachineB try to access files on MachineA. Which of the two should MachineB connect to? There is something else called 'competing consumer pattern', but that's of later concerns ;-)
If you need more help, feel free to ask at https://discuss.particular.net/ where more NServiceBus community members are located, as well as engineers of NServiceBus itself.
For some reason, it helped to make a request inside a task:
Task.Run(async () => await messageSession.Request<CreateDeviceResponse>(request))
I still not understand what is the problem, but it works only with such implementation.
In .net core web API, it works even without Task.Run, so I believe it has something to do with the fact that I am making this request in asp net mvc 4.7.2
I'm using WebApi Core 2.2. The Microsoft OData Client is adding a new parent record plus a subrecord (Deal+DealFee) from a WPF application. I'm hosting in IIS on Windows 10.
When I call container.SaveChanges(), it successfully calls the service to add the parent Deal record, but then it does a SECOND POST operation to this url (this is generated by the MS odata client lib):
POST http://localhost/mysite/odata/Deals(14)/DealFees
(note this includes the ID 14 which was just generated when adding the Deal)
This is two separate POSTs from the MS odata client lib, not a "deep insert" apparently. However, this results in a 404 (NotFound), which I can observe in Fiddler. The following urls DO work perfectly:
/odata/Deals
/odata/Deals(14)
/odata/DealFees
It seems like either the WebApi Core 2.2 service is not handling the POST to /Deals(14)/DealFees path, OR /Deals(14)/DealFees isn't a valid odata Uri? Is this kind of path generally supported in OData?
I don't know. Can anyone shed some light on what's going on?
Deep insert is not supported in WebAPI OData as of now. To me, it seems like the client is updating the resource set and the resource set for the navigation with two separate post requests and the reason you are getting a 404 is that there is no action mapped to the second request URI in the service.
The service can support this either by introducing a PostToDealFeesFromDeals controller action with default OData routing convention or use attribute routing to map the action for such requests.
If the action already exists then it might be that the first request did not finish creating the new record and the second request was fired, hence 404.
So, I am creating an application which will be using flowable.
We can say that once my application starts, it's gonna start a particular process deployed on flowable, proceed ahead accordingly.
So, in a way there will be lot of talking between flowable and other application, but for now suppose I just want to call flowable applications from POSTMAN (outside FLOWABLE).
I have used 3 modules: flowable-idm, flowable-modeler, flowable-task in my application.
Everything works fine when I am starting my deployed process from UI of flowable task, problems come when I want to start the processInstance using REST endpoint.
In flowable-task application, there is already a REST endpoint to start the process deployed: http://localhost:8080/flowable-task/app/rest/process-instances.
Now, if I call this from Swagger of flowable-task application, it works fine.
But it doesn't work when I try to call it from another application or POSTMAN for now (once POSTMAN call works, I can make the same arrangement in code), where I'm doing a basic auth and providing what's required in body.
Also, there is no error or exception displayed on console, I believe that is because of something catching that error or exception and not displaying anything.
However, to overcome the problem of starting process from POSTMAN, I can use REST endpoint http://localhost:9999/flowable-task/process-api/runtime/process-instances, but this is just a workaround, in future if I create new endpoints I would have to figure out a way to call those endpoints.
I saw this post and I guess this guy was also trying to achieve something similar but for flowable-modeler.
It's been suggested to make changes in SecurityConfiguration.java of flowable-task-conf module for my case, but I haven't done such changes before so not exactly sure where to start and how to proceed.
So, my question is how to talk to flowable-applications from outside flowable applications.
Edit:
Forum post about getting exception when imported flowable-rest module in workspace
The flowable-task UI Application is an example application that exposes non public REST API for the UI. However, the application also exposes the full REST API of Flowable.
There is also the flowable-rest application that has the Swagger doc and exposes the full REST API without a UI.
You would want to communicate with those REST endpoints.
The endpoints are under the following contexts:
process-api for the Process Engine
cmmn-api for the CMMN Engine
dmn-api for the DMN Engine
idm-api for the IDM Engine
form-api for the Form Engine
content-api for the Content Engine
For your example you would need to use POST to /process-api/runtime/process-instances for Starting a Process Instance
I'm new to ASP.NET Web API and I'm struggling with a very strange problem.
I have some code which calls a RESTful service and it executes fine from a console project, but I can't get it to run from an MVC4 project running under .NET 4.0
The code to call the service is very simple:
internal string Test()
{
using (var client = new HttpClient())
{
client.BaseAddress = new Uri("https://testserver");
var task = client.GetAsync("/someUri")
var response = task.Result;
response.EnsureSuccessStatusCode();
return response.Content.ReadAsStringAsync().Result;
}
}
As mentioned, called from a console project it works as expected and I get a response in milliseconds, however if I call the method from an action in my MVC4 controller after a few seconds I get a message stating that:
"A connection attempt failed because the connected party did not properly respond after a period of time, or established connection failed because connected host has failed to repond".
Weirdly, when debugging the MVC4 version, the task status always shows as WaitingForActivation.
Running fiddler doesn't show any request being made from the MVC4 version, but again does for the Console version.
After a fairly serious bit of googling I can't find anyone else who seems to have had this problem, so I'm guessing that I've fundamentally misunderstood something, but at the moment I'm not sure what!
Updated 16:55 BST, 11/09/2012
To make things even weirder, I've just created a new MVC4 site and I can call the method without any problems! I'm now trying to compare the sites, however one was an existing site that was upgraded to MVC4 and the other is a new blank site, so spotting the relevant difference could be tricky.
Updated 16:44 BST, 14/09/2012
This is now looking like some infrastructure / networking issue.
I upgraded the project to VS2012 with .NET 4.5 so that I could use async/await to try the suggested implementations to avoid a deadlock. This didn't change anything so I went back to square 1.
I created a new solution with a new MVC4 project, a new services library and a unit test project to run the service library outside of MVC.
In the service library I created one method to call a public "what's my IP" service, and another to call a company service that's exposed publicly but only responds properly to company IP addresses.
For some background, I connect in to the company LAN via a VPN.
When disconnected from the VPN, in both unit tests and MVC, the IP service responds HTTP 200, the company service responds HTTP 404 as expected.
When connected to the VPN, unit tests both respond HTTP 200, MVC both timeout.
Next I ran MS Soap Tool locally and used that to proxy calls to the company services. All calls (whether from unit tests or MVC) show a request and response, but the unit test registers the response whilst the MVC controller does not.
My only other thought is that it could be something to do with the size of the reply? All the "successes" have very small replies other than the unit test calling the company service?
The Microsoft recommended way to upgrade an MVC3 to MVC4 site is to start with a completely new MVC4 site a migrate your views, controllers & code over. So I think that your upgrade steps may be part of your issue, since you were able to get it to work in the new MVC4 site you created. If you need to manually upgrade your existing site, I would follow the steps outlined in Upgrading ASP.NET MVC 3 Project to ASP.NET MVC 4