Merge pull request #10072 from murgatroid99/node_uv_default

Switch Node back to using libuv iomgr by default

binding.gyp

@@ -39,11 +39,9 @@
 {
   'variables': {
     'runtime%': 'node',
-    # UV integration in C core is disabled by default while bugs are ironed
+    # UV integration in C core is enabled by default. It can be disabled
-    # out. It can be re-enabled for one build by setting the npm config
+    # by setting this argument to anything else.
-    # variable grpc_uv to true, and it can be re-enabled permanently by
+    'grpc_uv%': 'true',
-    # setting it to true here.
-    'grpc_uv%': 'false',
     # Some Node installations use the system installation of OpenSSL, and on
     # some systems, the system OpenSSL still does not have ALPN support. This
     # will let users recompile gRPC to work without ALPN.

src/core/lib/iomgr/timer_uv.c

@@ -78,6 +78,10 @@ void grpc_timer_init(grpc_exec_ctx *exec_ctx, grpc_timer *timer,
   uv_timer->data = timer;
   timer->uv_timer = uv_timer;
   uv_timer_start(uv_timer, run_expired_timer, timeout, 0);
+  /* We assume that gRPC timers are only used alongside other active gRPC
+     objects, and that there will therefore always be something else keeping
+     the uv loop alive whenever there is a timer */
+  uv_unref((uv_handle_t *)uv_timer);
 }
 
 void grpc_timer_cancel(grpc_exec_ctx *exec_ctx, grpc_timer *timer) {

templates/binding.gyp.template

@@ -41,11 +41,9 @@
   {
     'variables': {
       'runtime%': 'node',
-      # UV integration in C core is disabled by default while bugs are ironed
+      # UV integration in C core is enabled by default. It can be disabled
-      # out. It can be re-enabled for one build by setting the npm config
+      # by setting this argument to anything else.
-      # variable grpc_uv to true, and it can be re-enabled permanently by
+      'grpc_uv%': 'true',
-      # setting it to true here.
-      'grpc_uv%': 'false',
       # Some Node installations use the system installation of OpenSSL, and on
       # some systems, the system OpenSSL still does not have ALPN support. This
       # will let users recompile gRPC to work without ALPN.