Implementing web worker like wrapper around nsIThreadManager (inspire…

…d by kriszyp)

lib/worker-engine.js

@@ -0,0 +1,13 @@
+const Cc = Components.classes;
+const Ci = Components.interfaces;
+const Cu = Components.utils;
+
+var fs = require("file");
+
+exports.createEnvironment = function createEnvironment() {
+    var workerGlobal = Cu.Sandbox(Cc["@mozilla.org/systemprincipal;1"].createInstance(Ci.nsIPrincipal));
+    var bootstrapPath = system.enginePrefix + "/bootstrap.js";
+    Cu.evalInSandbox(fs.read(bootstrapPath), workerGlobal, "1.8", bootstrapPath, 0);
+    return workerGlobal;
+};
+

lib/worker.js

@@ -0,0 +1,90 @@
+const Cc = Components.classes;
+const Ci = Components.interfaces;
+const Cu = Components.utils;
+const ThreadManager = Cc["@mozilla.org/thread-manager;1"].getService();
+
+function Message(trigger) {
+    this.trigger = trigger;
+}
+Message.prototype = {
+    QueryInterface: function(iid) {
+        if (iid.equals(Ci.nsIRunnable) || iid.equals(Ci.nsISupports)) return this;
+        throw Components.results.NS_ERROR_NO_INTERFACE;
+    },
+    run: function() {
+        this.trigger();
+    }
+};
+
+var workerEngine = require("worker-engine");
+var Worker = exports.Worker = function Worker(scriptName) {
+    var main = ThreadManager.mainThread;
+    return createWorker(scriptName, function(thread, global) {
+        var worker = createPort(main, global);
+        createPort(thread, worker, global);
+        return worker;
+    });
+};
+
+function createPort(thread, target, port) {
+    target.onmessage = true; // give it something to feature detect off of
+    port = port || {};
+    port.postMessage = function(message) {
+        try {
+            thread.dispatch(new Message(function() {
+                var event = {
+                    //when is supposed to be the target, and when the ports? The spec is confusing
+                    target: target,
+                    ports: [target],
+                    data: message.toString(),
+                }
+                if (typeof target.onmessage == "function") target.onmessage(event);
+            }), thread.DISPATCH_NORMAL);
+        } catch(e) {
+            if (typeof target.onerror == "function") target.onerror(e);
+            else Components.utils.reportError(e);
+        }
+    };
+    port.postData = function(message) {
+        try {
+            thread.dispatch(new Message(function() {
+                var event = {
+                    ports: [target],
+                    // this can be optimized to be much faster
+                    data: target.JSON.parse(JSON.stringify(message)),
+                }
+                if (typeof target.ondata == "function") target.ondata(event);
+            }), thread.DISPATCH_NORMAL);
+        } catch(e) {
+            if (typeof target.onerror == "function") target.onerror(e);
+            else Components.utils.reportError(e);
+        }
+    };
+    return port;
+};
+
+
+function createWorker(scriptName, setup) {
+    var thread = ThreadManager.newThread(0);
+    var workerGlobal = workerEngine.createEnvironment();
+
+    // add the module lookup paths from our environment
+    var paths = workerGlobal.require.paths;
+    paths.splice(0, paths.length);
+    paths.push.apply(paths, require.paths);
+
+    // calback for dedicated and shared workers to do their thing
+    var worker = setup(thread, workerGlobal);
+    worker.terminate = function() {
+        thread.shutdown();
+    };
+    // there must be one and only one shared worker map amongst all workers
+    // workerGlobal.require("system").__sharedWorkers__ = system.__sharedWorkers__;
+
+    thread.dispatch(new Message(function() {
+            workerGlobal.require(scriptName);
+        }), thread.DISPATCH_NORMAL);
+    return worker;
+};
+
+

tests/all-tests.js

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+exports.testWorker = require("./test-worker");
+if (require.main === module.id)
+    require("os").exit(require("test/runner").run(exports));
+

tests/test-worker.js

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+var assert = require("test/assert");
+var Worker = require("worker").Worker;
+
+exports["test - demo"] = function() {
+    assert.isEqual(1, 1);
+};
+
+
+if (module.id == require.main)
+    require('os').exit(require('test/runner').run(exports));
+

tests/thread.js

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+var fs = require("file");
+onmessage = function(event) {
+    var n = parseInt(event.data);
+
+    for (var i = 1; i < n; i++) {
+        postMessage(i);
+    }
+};
+