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Hi,
I am looking on how to implement a CallBack Handler to a Web API Controller. I basically need to process the response send back by my external client.
I basically want to call the WebAPI controller from my portal so that I can place/initiate a Request to my external client. Once this client does the required actions at their end, they will need to send a CallBack so that I can process the response.
Appreciate a feedback on the above.
Regards
SSP
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Hi @Soni Samuel Panackacheril ,
implement a CallBack Handler to a Web API Controller.
Do you want to define APIs with callbacks?You cam use the new Func<...>, Action<...>, or Expression<...> types instead of custom delegates, when defining APIs with callbacks.
Hi @Yihui Sun-MSFT ,
In your opinion, which would be a best approach Func<...>, Action<...>, or Expression<...>?
Appreciate if you can point to me to an example to have an idea.
Regards,
Hi @Soni Samuel Panackacheril ,
I'm sorry I seemed to have misunderstood your meaning before. The API you are talking about looks like Web API.
I want to confirm with you:according to your description, is your request process like this?
In this case (if you are using HttpClient to send requests), you do not need to use "callbacks". In other words, you can use async-await.**You can refer to **this link.
Hi @Yihui Sun-MSFT ,
Thanks for getting back. Yes you are correct we are using Web API (Client B) as the Service Layer. However the Call from A (Web Portal) to B is through client side ($.Ajax).
The External Client (C) is a public enitity which we are integrating with through their SDK i.e. Call from B to C is from the WebAPI through the external client's SDK. So we are not using HttpClient to send request between Client B & Client C.
So the whole idea is for the Client C to have a Callback to Client B (Web API) in order to provide with the Response once they are done.
Thanks.
Hi @Soni Samuel Panackacheril ,
I understand that B will return the result to A only after ensuring that C has completed its job.
However, you don't need to implement the callback because the SDK you are using should send a request to the C client and will get response when the C client complete its work. Here the SDK (some classes inside) behaves similar to the HttpClient.
Would you mind telling me what SDK you are using? I'd like to help you check its usage.
Note: If you only confirm the question, you can write a "comment" directly. If there is a solution, you can write an "answer".