Merge pull request #23876 from yulin-liang/non-ok-status

Don't consider receiving non-OK status as an error for Cronet

src/core/ext/transport/cronet/transport/cronet_transport.cc

@@ -295,31 +295,6 @@ static void null_and_maybe_free_read_buffer(stream_obj* s) {
   s->state.rs.read_buffer = nullptr;
 }
 
-static void maybe_flush_read(stream_obj* s) {
-  /* To enter flush read state (discarding all the buffered messages in
-   * transport layer), two conditions must be satisfied: 1) non-zero grpc status
-   * has been received, and 2) an op requesting the status code
-   * (RECV_TRAILING_METADATA) is issued by the user. (See
-   * doc/status_ordering.md) */
-  /* Whenever the evaluation of any of the two condition is changed, we check
-   * whether we should enter the flush read state. */
-  if (s->state.pending_recv_trailing_metadata && s->state.fail_state) {
-    if (!s->state.flush_read && !s->state.rs.read_stream_closed) {
-      CRONET_LOG(GPR_DEBUG, "%p: Flush read", s);
-      s->state.flush_read = true;
-      null_and_maybe_free_read_buffer(s);
-      s->state.rs.read_buffer =
-          static_cast<char*>(gpr_malloc(GRPC_FLUSH_READ_SIZE));
-      if (!s->state.pending_read_from_cronet) {
-        CRONET_LOG(GPR_DEBUG, "bidirectional_stream_read(%p)", s->cbs);
-        bidirectional_stream_read(s->cbs, s->state.rs.read_buffer,
-                                  GRPC_FLUSH_READ_SIZE);
-        s->state.pending_read_from_cronet = true;
-      }
-    }
-  }
-}
-
 static void read_grpc_header(stream_obj* s) {
   s->state.rs.read_buffer = s->state.rs.grpc_header_bytes;
   s->state.rs.remaining_bytes = GRPC_HEADER_SIZE_IN_BYTES;
@@ -359,7 +334,6 @@ static void add_to_storage(struct stream_obj* s,
   }
   if (op->recv_trailing_metadata) {
     s->state.pending_recv_trailing_metadata = true;
-    maybe_flush_read(s);
   }
   CRONET_LOG(GPR_DEBUG, "adding new op %p. %d in the queue.", new_op,
              storage->num_pending_ops);
@@ -569,11 +543,10 @@ static void on_response_headers_received(
   for (size_t i = 0; i < headers->count; i++) {
     if (0 == strcmp("grpc-status", headers->headers[i].key)) {
       on_response_trailers_received(stream, headers);
-      /* Do an extra read for a trailer-only stream with grpc_status = 0
-       to trigger on_succeeded() callback */
-      if (0 == strcmp(headers->headers[i].value, "0")) {
-        read_grpc_header(s);
-      }
+
+      /* Do an extra read for a trailer-only stream to trigger on_succeeded()
+       * callback */
+      read_grpc_header(s);
       return;
     }
   }
@@ -670,13 +643,6 @@ static void on_response_trailers_received(
   if (trailers->count > 0) {
     s->state.rs.trailing_metadata_valid = true;
   }
-  for (size_t i = 0; i < trailers->count; i++) {
-    if (0 == strcmp(trailers->headers[i].key, "grpc-status") &&
-        0 != strcmp(trailers->headers[i].value, "0")) {
-      s->state.fail_state = true;
-      maybe_flush_read(s);
-    }
-  }
   s->state.state_callback_received[OP_RECV_TRAILING_METADATA] = true;
   /* Send a EOS when server terminates the stream (testServerFinishesRequest) to
    * trigger on_succeeded */

src/objective-c/tests/CronetTests/CoreCronetEnd2EndTests.mm

@@ -347,6 +347,10 @@ static char *roots_filename;
   [self testIndividualCase:(char *)"server_finishes_request"];
 }
 
+- (void)testServerStreaming {
+  [self testIndividualCase:(char *)"server_streaming"];
+}
+
 - (void)testShutdownFinishesCalls {
   [self testIndividualCase:(char *)"shutdown_finishes_calls"];
 }