ProcessingRequest.Builder creating a request with both headers and body

[yoav-sentinel]

Title: Create a ProcessingRequest that has both headers and body

Description:
I have an external processor service and in my tests I'm creating a ProcessingRequest to be sent to it, to test my external processing logic.

I'm now trying to create a ProcessingRequest entity with headers and body, while it seems the ProcessingRequest.Builder is using a disjoint case-based approach (requestCase_).

    private static ProcessingRequest addRequestBody(HttpHeaders headers, HttpBody body) {
        return ProcessingRequest.newBuilder()
                .setRequestHeaders(headers)
                .setRequestBody(body)
                .build();
    }

// Returned request:
// request_body {
//   body: "{\"key\": \"value\"}"
// }

Therefore, the setRequestHeaders returns a Builder just for headers (requestCase_ = 2), and then setRequestBody replaces the earlier with a new Builder just for body (requestCase_ = 4).

Am I missing something? Or it is not supported to create a request with more than one case?

[zuercher]

Per the proto definition only one of request_headers or request_body may be set (among other fields).

I've not used the ext_proc filter myself, but the docs suggest to me that as envoy receives request headers, request body, request trailers, response headers, response body, or response_trailers it checks the filter configuration's processing_mode and may send a matching ProcessingRequest to the external processor service. To process request headers and request body, your service will need to handle two separate ProcessingMessage instances.