How Asio client is aware of server terminating connection via GOAWAY with error code 0

[soumyakantiroychowdhury]

When a http/2 server closes the connection gracefully by sending GOAWAY frame with error code 0, how does the asio http2 client can communicate this to the upper layer? The on_error callback of the session class is not called in this scenario, which is expected.

[louygan]

found issue in asio_client_session_impl.cc

according to nghttp2/examples/client.c
NGHTTP2_RST_STREAM and NGHTTP2_GOWAY should be handled.

246 static int on_frame_recv_callback(nghttp2_session *session,
247 const nghttp2_frame *frame, void *user_data) {
248 size_t i;
249 (void)user_data;
250
251 switch (frame->hd.type) {
252 case NGHTTP2_HEADERS:
253 if (frame->headers.cat == NGHTTP2_HCAT_RESPONSE) {
254 const nghttp2_nv *nva = frame->headers.nva;
255 struct Request *req;
256 req = nghttp2_session_get_stream_user_data(session, frame->hd.stream_id);
257 if (req) {
258 printf("[INFO] C <---------------------------- S (HEADERS)\n");
259 for (i = 0; i < frame->headers.nvlen; ++i) {
260 fwrite(nva[i].name, 1, nva[i].namelen, stdout);
261 printf(": ");
262 fwrite(nva[i].value, 1, nva[i].valuelen, stdout);
263 printf("\n");
264 }
265 }
266 }
267 break;
268 case NGHTTP2_RST_STREAM:
269 printf("[INFO] C <---------------------------- S (RST_STREAM)\n");
270 break;
271 case NGHTTP2_GOAWAY:
272 printf("[INFO] C <---------------------------- S (GOAWAY)\n");
273 break;
274 }
275 return 0;
276 }