FailFast(false), return helpful error message when context is time out

picker_wrapper.go

@@ -120,6 +120,14 @@ func (bp *pickerWrapper) pick(ctx context.Context, failfast bool, opts balancer.
  bp.mu.Unlock()
  select {
  case <-ctx.Done():
+ if connectionErr := bp.connectionError(); connectionErr != nil {
+ switch ctx.Err() {
+ case context.DeadlineExceeded:
+ return nil, nil, status.Errorf(codes.DeadlineExceeded, "latest connection error: %v", connectionErr)
+ case context.Canceled:
+ return nil, nil, status.Errorf(codes.Canceled, "latest connection error: %v", connectionErr)
+ }
+ }
  return nil, nil, ctx.Err()
  case <-ch:
  }

test/end2end_test.go

@@ -6642,6 +6642,29 @@ func (s) TestFailFastRPCErrorOnBadCertificates(t *testing.T) {
  te.t.Fatalf("TestService/EmptyCall(_, _) = _, %v, want err.Error() contains %q", err, clientAlwaysFailCredErrorMsg)
 }
 
+func (s) TestWaitForReadyRPCErrorOnBadCertificates(t *testing.T) {
+ te := newTest(t, env{name: "bad-cred", network: "tcp", security: "clientAlwaysFailCred", balancer: "round_robin"})
+ te.startServer(&testServer{security: te.e.security})
+ defer te.tearDown()
+
+ opts := []grpc.DialOption{grpc.WithTransportCredentials(clientAlwaysFailCred{})}
+ dctx, dcancel := context.WithTimeout(context.Background(), 10*time.Second)
+ defer dcancel()
+ cc, err := grpc.DialContext(dctx, te.srvAddr, opts...)
+ if err != nil {
+ t.Fatalf("Dial(_) = %v, want %v", err, nil)
+ }
+ defer cc.Close()
+
+ tc := testpb.NewTestServiceClient(cc)
+ ctx, cancel := context.WithTimeout(context.Background(), 5*time.Second)
+ defer cancel()
+ if _, err = tc.EmptyCall(ctx, &testpb.Empty{}, grpc.WaitForReady(true)); strings.Contains(err.Error(), clientAlwaysFailCredErrorMsg) {
+ return
+ }
+ te.t.Fatalf("TestService/EmptyCall(_, _) = _, %v, want err.Error() contains %q", err, clientAlwaysFailCredErrorMsg)
+}
+
 func (s) TestRPCTimeout(t *testing.T) {
  for _, e := range listTestEnv() {
  testRPCTimeout(t, e)