The following article on Microsoft illustrates a good pattern for Asynchronous Request-Reply pattern over HTTP - https://docs.microsoft.com/en-us/azure/architecture/patterns/async-request-reply
Excerpts from the article:
- The client sends a request and receives an HTTP 202 (Accepted) response.
- The client sends an HTTP GET request to the status endpoint. The work is still pending, so this call also returns HTTP 202.
- At some point, the work is complete and the status endpoint returns 302 (Found) redirecting to the resource.
- The client fetches the resource at the specified URL.