Attach to all RelayProfiler events

Summary: public

Dynamically profile events from RelayProfiler if available. This will expose time spent in Relay in the systraces.

Reviewed By: tadeuzagallo

Differential Revision: D2674215

fb-gh-sync-id: d5f9d529b86d267a80b0cda2223f6a28a08ac385

Libraries/JavaScriptAppEngine/Initialization/InitializeJavaScriptAppEngine.js

@@ -160,7 +160,9 @@ function setUpWebSockets() {
 
 function setUpProfile() {
   if (__DEV__) {
-    require('BridgeProfiling').swizzleReactPerf();
+    var BridgeProfiling = require('BridgeProfiling');
+    BridgeProfiling.swizzleReactPerf();
+    BridgeProfiling.attachToRelayProfiler();
   }
 }
 

Libraries/Utilities/BridgeProfiling.js

@@ -61,6 +61,24 @@ var BridgeProfiling = {
   swizzleReactPerf() {
     ReactPerf().injection.injectMeasure(BridgeProfiling.reactPerfMeasure);
   },
+
+  attachToRelayProfiler() {
+    // We don't want to create a dependency on `RelayProfiler`, so that's why
+    // we require it indirectly (rather than using a literal string). Since
+    // there's no guarantee that the module will be present, we must wrap
+    // everything in a try-catch block as requiring a non-existing module
+    // will just throw.
+    try {
+      var rpName = 'RelayProfiler';
+      var RelayProfiler = require(rpName);
+      RelayProfiler.attachProfileHandler('*', (name) => {
+        BridgeProfiling.profile(name);
+        return () => {
+          BridgeProfiling.profileEnd();
+        };
+      });
+    } catch(err) {}
+  }
 };
 
 BridgeProfiling.setEnabled(global.__RCTProfileIsProfiling || false);