逻辑应用程序 - 对 API 的 HTTP 连接器 POST 调用返回 202 和位置标头，但轮询返回 404

Question

We have implemented a Logic app to call do a POST call to a third-party API which returns a 202 with location header. The Logic app in the backend automatically polls using the location header resulting in GET request to the third-party provider hoping to receive a 200 response once the processing is complete. However, the GET requests are resulting in 404 errors.

We have tried disabling the check location headers but for some reason Logic apps still continues to send the GET requests and at a faster rate.

Is there any way to stop the GET request from Logic Apps or should this be the third-party provider's responsibility to handle the polling and not send 404's?

Answer 1

Yes, you can stop the GET request from your Logic Apps. Basically it totally depends on your workflow. If you are designing a stateful workflow then I would suggest that not to stop the GET request.

For stateful workflow all HTTP-based actions follow the standard asynchronous operation pattern as the default behavior. Where after an HTTP action calls or sends a request to an endpoint or API, the receiver immediately returns a "202 ACCEPTED" response. And the response can include a location header which the caller can use to poll or check the status for the asynchronous request until the receiver stops processing and returns a " 200 OK " success response or other non-202 response.

But if you are designing a stateless workflow , then caller doesn't have to wait for the request to finish processing and can continue to run the next action. In this case the receiver return the "202 ACCEPTED" response as-is, and proceed to the next step in the workflow execution. A stateless workflow won't poll the specified URI to check the status .

You can stop the GET request from your logic app by following any of the two approaches mentioned below.

1. Turn off Asynchronous Pattern setting.

   You can achieve this by going to the Logic App Designer, on the HTTP action's title bar, selecting the ellipses ( ... ) button and setting Asynchronous Pattern to Off if enabled.

2. Disable asynchronous pattern in HTTP action's JSON definition .

   In the HTTP action's underlying JSON definition, add the "DisableAsyncPattern" operation option to the action's definition so that the action follows the synchronous operation pattern. Check this document for more information.

Also check this Asynchronous request-response behavior document by Microsoft for more understanding.