grpclb: skip slash in server uri path if present

src/core/ext/lb_policy/grpclb/grpclb.c

@@ -768,8 +768,14 @@ static grpc_lb_policy *glb_create(grpc_exec_ctx *exec_ctx,
   arg = grpc_channel_args_find(args->args, GRPC_ARG_SERVER_URI);
   GPR_ASSERT(arg != NULL);
   GPR_ASSERT(arg->type == GRPC_ARG_STRING);
-  grpc_uri *uri = grpc_uri_parse(arg->value.string, 1);
-  glb_policy->server_name = gpr_strdup(uri->path);
+  grpc_uri *uri = grpc_uri_parse(arg->value.string, true);
+  GPR_ASSERT(uri->path[0] != '\0');
+  glb_policy->server_name =
+      gpr_strdup(uri->path[0] == '/' ? uri->path + 1 : uri->path);
+  if (grpc_lb_glb_trace) {
+    gpr_log(GPR_INFO, "Will use '%s' as the server name for LB request.",
+            glb_policy->server_name);
+  }
   grpc_uri_destroy(uri);
 
   /* All input addresses in addresses come from a resolver that claims

test/cpp/grpclb/grpclb_test.cc

@@ -659,7 +659,7 @@ static test_fixture setup_test_fixture(int lb_server_update_delay_ms) {
   char *server_uri;
   // The grpclb LB policy will be automatically selected by virtue of
   // the fact that the returned addresses are balancer addresses.
-  gpr_asprintf(&server_uri, "test:%s?lb_enabled=1",
+  gpr_asprintf(&server_uri, "test:///%s?lb_enabled=1",
                tf.lb_server.servers_hostport);
   setup_client(server_uri, &tf.client);
   gpr_free(server_uri);