#15.1 Extend packager server to receive signals from Sampling Profiler

Reviewed By: bestander

Differential Revision: D3606098

fbshipit-source-id: ec55030dd1b3a27f0595650da1ce01fe1ac9116c

local-cli/server/middleware/jscProfilerMiddleware.js

@@ -0,0 +1,36 @@
+/**
+ * Copyright (c) 2015-present, Facebook, Inc.
+ * All rights reserved.
+ *
+ * This source code is licensed under the BSD-style license found in the
+ * LICENSE file in the root directory of this source tree. An additional grant
+ * of patent rights can be found in the PATENTS file in the same directory.
+ */
+'use strict';
+
+const fs = require('fs');
+
+module.exports = function(req, res, next) {
+  if (req.url !== '/jsc-profile') {
+    next();
+    return;
+  }
+
+  console.log('Dumping JSC profile information...');
+  const dumpName = '/tmp/jsc-profile_' + Date.now() + '.cpuprofile';
+  fs.writeFile(dumpName, req.rawBody, (err) => {
+    var response = '';
+    if (err) {
+      response =
+        'An error occured when trying to save the profile at ' + dumpName;
+      console.error(response, err);
+    } else {
+      response =
+        'Your profile was generated at\n\n' + dumpName + '\n\n' +
+        'Open `Chrome Dev Tools > Profiles > Load` '
+        + 'and select the profile to visualize it.';
+      console.log(response);
+    }
+    res.end(response);
+  });
+};

local-cli/server/runServer.js

@@ -13,6 +13,7 @@ const connect = require('connect');
 const cpuProfilerMiddleware = require('./middleware/cpuProfilerMiddleware');
 const getDevToolsMiddleware = require('./middleware/getDevToolsMiddleware');
 const http = require('http');
+const jscProfilerMiddleware = require('./middleware/jscProfilerMiddleware');
 const loadRawBodyMiddleware = require('./middleware/loadRawBodyMiddleware');
 const messageSocket = require('./util/messageSocket.js');
 const openStackFrameInEditorMiddleware = require('./middleware/openStackFrameInEditorMiddleware');
@@ -41,6 +42,7 @@ function runServer(args, config, readyCallback) {
     .use(systraceProfileMiddleware)
     .use(heapCaptureMiddleware)
     .use(cpuProfilerMiddleware)
+    .use(jscProfilerMiddleware)
     .use(indexPageMiddleware)
     .use(packagerServer.processRequest.bind(packagerServer));