Method executor

src/slave/http.cpp:730–891

Future<Response> Http::executor(
    const Request& request,
    const Option<Principal>& principal) const
{
  if (!slave->recoveryInfo.reconnect) {
    CHECK_EQ(slave->state, Slave::RECOVERING);
    return ServiceUnavailable("Agent has not finished recovery");
  }

  // TODO(anand): Add metrics for rejected requests.

  if (request.method != "POST") {
    return MethodNotAllowed({"POST"}, request.method);
  }

  v1::executor::Call v1Call;

  Option<string> contentType = request.headers.get("Content-Type");
  if (contentType.isNone()) {
    return BadRequest("Expecting 'Content-Type' to be present");
  }

  if (contentType.get() == APPLICATION_PROTOBUF) {
    if (!v1Call.ParseFromString(request.body)) {
      return BadRequest("Failed to parse body into Call protobuf");
    }
  } else if (contentType.get() == APPLICATION_JSON) {
    Try<JSON::Value> value = JSON::parse(request.body);
    if (value.isError()) {
      return BadRequest("Failed to parse body into JSON: " + value.error());
    }

    Try<v1::executor::Call> parse =
      ::protobuf::parse<v1::executor::Call>(value.get());

    if (parse.isError()) {
      return BadRequest("Failed to convert JSON into Call protobuf: " +
                        parse.error());
    }

    v1Call = parse.get();
  } else {
    return UnsupportedMediaType(
        string("Expecting 'Content-Type' of ") +
        APPLICATION_JSON + " or " + APPLICATION_PROTOBUF);
  }

  const executor::Call call = devolve(v1Call);

  Option<Error> error = common::validation::validateExecutorCall(call);

  if (error.isSome()) {
    return BadRequest("Failed to validate Executor::Call: " + error->message);
  }

  ContentType acceptType;

  if (call.type() == executor::Call::SUBSCRIBE) {