Bug 804910 - Part 1. Check for worker load failures and send a notification in case of errors. r=felipe

toolkit/components/social/FrameWorker.jsm

@@ -183,8 +183,17 @@ FrameWorker.prototype = {
     // removed - at which time we've explicitly killed it anyway.
     let worker = this;
 
-    workerWindow.addEventListener("load", function loadListener() {
-      workerWindow.removeEventListener("load", loadListener);
+    workerWindow.addEventListener("DOMContentLoaded", function loadListener() {
+      workerWindow.removeEventListener("DOMContentLoaded", loadListener);
+
+      // no script, error out now rather than creating ports, etc
+      let scriptText = workerWindow.document.body.textContent.trim();
+      if (!scriptText) {
+        Cu.reportError("FrameWorker: Empty worker script received");
+        Services.obs.notifyObservers(null, "social:frameworker-error", worker.url);
+        return;
+      }
+
       // the iframe has loaded the js file as text - first inject the magic
       // port-handling code into the sandbox.
       try {
@@ -193,6 +202,8 @@ FrameWorker.prototype = {
       }
       catch (e) {
         Cu.reportError("FrameWorker: Error injecting port code into content side of the worker: " + e + "\n" + e.stack);
+        Services.obs.notifyObservers(null, "social:frameworker-error", worker.url);
+        return;
       }
 
       // and wire up the client message handling.
@@ -201,16 +212,18 @@ FrameWorker.prototype = {
       }
       catch (e) {
         Cu.reportError("FrameWorker: Error setting up event listener for chrome side of the worker: " + e + "\n" + e.stack);
+        Services.obs.notifyObservers(null, "social:frameworker-error", worker.url);
+        return;
       }
 
       // Now get the worker js code and eval it into the sandbox
       try {
-        let scriptText = workerWindow.document.body.textContent;
         Cu.evalInSandbox(scriptText, sandbox, "1.8", workerWindow.location.href, 1);
       } catch (e) {
         Cu.reportError("FrameWorker: Error evaluating worker script for " + worker.name + ": " + e + "; " +
             (e.lineNumber ? ("Line #" + e.lineNumber) : "") +
             (e.stack ? ("\n" + e.stack) : ""));
+        Services.obs.notifyObservers(null, "social:frameworker-error", worker.url);
         return;
       }
 
@@ -341,7 +354,11 @@ function initClientMessageHandler(worker, workerWindow) {
     }
     switch (data.portTopic) {
       // No "port-create" here - client ports are created explicitly.
-
+      case "port-connection-error":
+        // onconnect failed, we cannot connect the port, the worker has
+        // become invalid
+        Services.obs.notifyObservers(null, "social:frameworker-error", worker.url);
+        break;
       case "port-close":
         // the worker side of the port was closed, so close this side too.
         port = worker.ports[portid];

toolkit/components/social/MessagePortWorker.js

@@ -65,7 +65,14 @@ function __initWorkerMessageHandler() {
         port = new WorkerPort(portid);
         ports[portid] = port;
         // and call the "onconnect" handler.
-        onconnect({ports: [port]});
+        try {
+          onconnect({ports: [port]});
+        } catch(e) {
+          // we have a bad worker and cannot continue, we need to signal
+          // an error
+          port._postControlMessage("port-connection-error", JSON.stringify(e.toString()));
+          throw e;
+        }
         break;
 
       case "port-close":

toolkit/components/social/test/browser/browser_frameworker.js

@@ -463,5 +463,67 @@ let tests = {
       }
       ioService.offline = true;
     }
-  }
+  },
+  
+  testMissingWorker: function(cbnext) {
+    Services.obs.addObserver(function handleError() {
+      Services.obs.removeObserver(handleError, "social:frameworker-error");
+        ok(true, "social:frameworker-error was handled");
+        cbnext();
+    }, 'social:frameworker-error', false);
+    // don't ever create this file!  We want a 404.
+    let url = "https://example.com/browser/toolkit/components/social/test/browser/worker_is_missing.js";
+    let worker = getFrameWorkerHandle(url, undefined, "testMissingWorker");
+    worker.port.onmessage = function(e) {
+      ok(false, "social:frameworker-error was handled");
+      cbnext();
+    }
+  },
+
+  testNoConnectWorker: function(cbnext) {
+    Services.obs.addObserver(function handleError() {
+      Services.obs.removeObserver(handleError, "social:frameworker-error");
+        ok(true, "social:frameworker-error was handled");
+        cbnext();
+    }, 'social:frameworker-error', false);
+    let worker = getFrameWorkerHandle(makeWorkerUrl(function () {}),
+                                      undefined, "testNoConnectWorker");
+    worker.port.onmessage = function(e) {
+      ok(false, "social:frameworker-error was handled");
+      cbnext();
+    }
+  },
+
+  testEmptyWorker: function(cbnext) {
+    Services.obs.addObserver(function handleError() {
+      Services.obs.removeObserver(handleError, "social:frameworker-error");
+        ok(true, "social:frameworker-error was handled");
+        cbnext();
+    }, 'social:frameworker-error', false);
+    let worker = getFrameWorkerHandle("data:application/javascript;charset=utf-8,",
+                                      undefined, "testEmptyWorker");
+    worker.port.onmessage = function(e) {
+      ok(false, "social:frameworker-error was handled");
+      cbnext();
+    }
+  },
+
+  testWorkerConnectError: function(cbnext) {
+    Services.obs.addObserver(function handleError() {
+      Services.obs.removeObserver(handleError, "social:frameworker-error");
+        ok(true, "social:frameworker-error was handled");
+        cbnext();
+    }, 'social:frameworker-error', false);
+    let run = function () {
+      onconnect = function(e) {
+        throw new Error("worker failure");
+      }
+    }
+    let worker = getFrameWorkerHandle(makeWorkerUrl(run),
+                                      undefined, "testWorkerConnectError");
+    worker.port.onmessage = function(e) {
+      ok(false, "social:frameworker-error was handled");
+      cbnext();
+    }
+  },
 }