rpc/client: return request ID from send and add_request methods

User should know the request ID that was issued.

Change-Id: If1191f73b31ebe04f23a88a9ca31fa157474056b
Signed-off-by: Pawel Wodkowski <pawelx.wodkowski@intel.com>
Reviewed-on: https://review.gerrithub.io/c/spdk/spdk/+/449315
Reviewed-by: Karol Latecki <karol.latecki@intel.com>
Reviewed-by: Pawel Kaminski <pawelx.kaminski@intel.com>
Reviewed-by: Darek Stojaczyk <dariusz.stojaczyk@intel.com>
Reviewed-by: Shuhei Matsumoto <shuhei.matsumoto.xt@hitachi.com>
Tested-by: SPDK CI Jenkins <sys_sgci@intel.com>

scripts/rpc/client.py

@@ -86,6 +86,7 @@ class JSONRPCClient(object):
 
         self._logger.debug("append request:\n%s\n", json.dumps(req))
         self._reqs.append(req)
+        return self._request_id
 
     def flush(self):
         self._logger.debug("Flushing buffer")
@@ -96,8 +97,9 @@ class JSONRPCClient(object):
         self.sock.sendall(reqstr.encode("utf-8"))
 
     def send(self, method, params=None):
-        self.add_request(method, params)
+        id = self.add_request(method, params)
         self.flush()
+        return id
 
     def decode_one_response(self):
         try: