Merge pull request #85 from tmickel/feature/worker

Update to allow running in a WebWorker

.eslintrc

@@ -13,7 +13,8 @@
     },
     "env": {
         "node": true,
-        "browser": true
+        "browser": true,
+        "worker": true
     },
     "extends": "eslint:recommended"
 }

Makefile

@@ -2,6 +2,7 @@ ESLINT=./node_modules/.bin/eslint
 NODE=node
 TAP=./node_modules/.bin/tap
 WEBPACK=./node_modules/.bin/webpack --progress --colors
+WEBPACK_DEV_SERVER=./node_modules/.bin/webpack-dev-server
 
 # ------------------------------------------------------------------------------
 
@@ -11,6 +12,9 @@ build:
 watch:
 	$(WEBPACK) --watch
 
+serve:
+	$(WEBPACK_DEV_SERVER) --content-base ./
+
 # ------------------------------------------------------------------------------
 
 lint:

package.json

@@ -23,6 +23,7 @@
     "json-loader": "0.5.4",
     "scratch-blocks": "git+https://git@github.com/LLK/scratch-blocks.git",
     "tap": "5.7.1",
-    "webpack": "1.13.0"
+    "webpack": "1.13.0",
+    "webpack-dev-server": "1.14.1"
   }
 }

playground/index.html

@@ -255,8 +255,8 @@
     <script src="../node_modules/scratch-blocks/blockly_compressed_vertical.js"></script>
     <script src="../node_modules/scratch-blocks/blocks_compressed.js"></script>
     <script src="../node_modules/scratch-blocks/blocks_compressed_vertical.js"></script>
-    <!-- Compiled VM -->
-    <script src="../vm.js"></script>
+    <!-- VM Worker -->
+    <script src="../vm.worker.js"></script>
     <!-- Playground -->
     <script src="./playground.js"></script>
 </body>

playground/playground.js

@@ -26,55 +26,61 @@ window.onload = function() {
     window.workspace = workspace;
 
     // Block events.
-    workspace.addChangeListener(vm.blockListener);
     // @todo: Re-enable flyout listening after fixing GH-69.
-    //var flyoutWorkspace = workspace.toolbox_.flyout_.workspace_;
-    //flyoutWorkspace.addChangeListener(vm.flyoutBlockListener);
+    workspace.addChangeListener(vm.blockListener);
 
+    // Playground data
     var blockexplorer = document.getElementById('blockexplorer');
-    workspace.addChangeListener(function() {
-        // On a change, update the block explorer.
-        blockexplorer.innerHTML = JSON.stringify(vm.runtime.blocks, null, 2);
+    var updateBlockExplorer = function(blocks) {
+        blockexplorer.innerHTML = JSON.stringify(blocks, null, 2);
         window.hljs.highlightBlock(blockexplorer);
-    });
+    };
 
     var threadexplorer = document.getElementById('threadexplorer');
     var cachedThreadJSON = '';
-    var updateThreadExplorer = function () {
-        var newJSON = JSON.stringify(vm.runtime.threads, null, 2);
+    var updateThreadExplorer = function (threads) {
+        var newJSON = JSON.stringify(threads, null, 2);
         if (newJSON != cachedThreadJSON) {
             cachedThreadJSON = newJSON;
             threadexplorer.innerHTML = cachedThreadJSON;
             window.hljs.highlightBlock(threadexplorer);
         }
-        window.requestAnimationFrame(updateThreadExplorer);
     };
-    updateThreadExplorer();
+
+    var getPlaygroundData = function () {
+        vm.getPlaygroundData();
+        window.requestAnimationFrame(getPlaygroundData);
+    };
+    getPlaygroundData();
+
+    vm.on('playgroundData', function(data) {
+        updateThreadExplorer(data.threads);
+        updateBlockExplorer(data.blocks);
+    });
 
     // Feedback for stacks and blocks running.
-    vm.runtime.on('STACK_GLOW_ON', function(blockId) {
-        workspace.glowStack(blockId, true);
+    vm.on('STACK_GLOW_ON', function(data) {
+        workspace.glowStack(data.id, true);
     });
-    vm.runtime.on('STACK_GLOW_OFF', function(blockId) {
-        workspace.glowStack(blockId, false);
+    vm.on('STACK_GLOW_OFF', function(data) {
+        workspace.glowStack(data.id, false);
     });
-    vm.runtime.on('BLOCK_GLOW_ON', function(blockId) {
-        workspace.glowBlock(blockId, true);
+    vm.on('BLOCK_GLOW_ON', function(data) {
+        workspace.glowBlock(data.id, true);
     });
-    vm.runtime.on('BLOCK_GLOW_OFF', function(blockId) {
-        workspace.glowBlock(blockId, false);
+    vm.on('BLOCK_GLOW_OFF', function(data) {
+        workspace.glowBlock(data.id, false);
     });
 
-
     // Run threads
-    vm.runtime.start();
+    vm.start();
 
     // Handlers for green flag and stop all.
     document.getElementById('greenflag').addEventListener('click', function() {
-        vm.runtime.greenFlag();
+        vm.greenFlag();
     });
     document.getElementById('stopall').addEventListener('click', function() {
-        vm.runtime.stopAll();
+        vm.stopAll();
     });
 
     var tabBlockExplorer = document.getElementById('tab-blockexplorer');

src/blocks/wedo2.js

@@ -64,7 +64,7 @@ WeDo2Blocks.prototype._motorOnFor = function(direction, durationSeconds, util) {
         YieldTimers.resolve(this._motorTimeout);
         this._motorTimeout = null;
     }
-    if (window.native) {
+    if (typeof window !== 'undefined' && window.native) {
         window.native.motorRun(direction, this._motorSpeed);
     }
 
@@ -73,7 +73,7 @@ WeDo2Blocks.prototype._motorOnFor = function(direction, durationSeconds, util) {
         if (instance._motorTimeout == myTimeout) {
             instance._motorTimeout = null;
         }
-        if (window.native) {
+        if (typeof window !== 'undefined' && window.native) {
             window.native.motorStop();
         }
         util.done();
@@ -132,7 +132,7 @@ WeDo2Blocks.prototype._getColor = function(colorName) {
 };
 
 WeDo2Blocks.prototype.setColor = function(argValues, util) {
-    if (window.native) {
+    if (typeof window !== 'undefined' && window.native) {
         var colorIndex = this._getColor(argValues[0]);
         window.native.setLedColor(colorIndex);
     }

src/engine/runtime.js

@@ -210,10 +210,6 @@ Runtime.prototype.stopAll = function () {
         // Actually remove the thread.
         this._removeThread(poppedThread);
     }
-    // @todo call stop function in all extensions/packages/WeDo stub
-    if (window.native) {
-        window.native.motorStop();
-    }
 };
 
 /**
@@ -243,12 +239,29 @@ Runtime.prototype.glowBlock = function (blockId, isGlowing) {
     }
 };
 
+/**
+ * setInterval implementation that works in a WebWorker or not.
+ * @param {?Function} fcn Function to call.
+ * @param {number} interval Interval at which to call it.
+ * @return {number} Value returned by setInterval.
+ */
+Runtime.prototype._setInterval = function(fcn, interval) {
+    var setInterval = null;
+    if (typeof window !== 'undefined' && window.setInterval) {
+        setInterval = window.setInterval;
+    } else if (typeof self !== 'undefined' && self.setInterval) {
+        setInterval = self.setInterval;
+    } else {
+        return;
+    }
+    return setInterval(fcn, interval);
+};
+
 /**
  * Set up timers to repeatedly step in a browser
  */
 Runtime.prototype.start = function () {
-    if (!window.setInterval) return;
-    window.setInterval(function() {
+    this._setInterval(function() {
         this._step();
     }.bind(this), Runtime.THREAD_STEP_INTERVAL);
 };

src/index.js

@@ -4,6 +4,12 @@ var util = require('util');
 var Blocks = require('./engine/blocks');
 var Runtime = require('./engine/runtime');
 
+/**
+ * Whether the environment is a WebWorker.
+ * @const{boolean}
+ */
+var ENV_WORKER = typeof importScripts === 'function';
+
 /**
  * Handles connections between blocks, stage, and extensions.
  *
@@ -28,6 +34,20 @@ function VirtualMachine () {
     instance.flyoutBlockListener = (
         instance.blocks.generateBlockListener(true, instance.runtime)
     );
+
+    // Runtime emits are passed along as VM emits.
+    instance.runtime.on(Runtime.STACK_GLOW_ON, function (id) {
+        instance.emit(Runtime.STACK_GLOW_ON, {id: id});
+    });
+    instance.runtime.on(Runtime.STACK_GLOW_OFF, function (id) {
+        instance.emit(Runtime.STACK_GLOW_OFF, {id: id});
+    });
+    instance.runtime.on(Runtime.BLOCK_GLOW_ON, function (id) {
+        instance.emit(Runtime.BLOCK_GLOW_ON, {id: id});
+    });
+    instance.runtime.on(Runtime.BLOCK_GLOW_OFF, function (id) {
+        instance.emit(Runtime.BLOCK_GLOW_OFF, {id: id});
+    });
 }
 
 /**
@@ -35,6 +55,88 @@ function VirtualMachine () {
  */
 util.inherits(VirtualMachine, EventEmitter);
 
+/**
+ * Start running the VM - do this before anything else.
+ */
+VirtualMachine.prototype.start = function () {
+    this.runtime.start();
+};
+
+/**
+ * "Green flag" handler - start all threads starting with a green flag.
+ */
+VirtualMachine.prototype.greenFlag = function () {
+    this.runtime.greenFlag();
+};
+
+/**
+ * Stop all threads and running activities.
+ */
+VirtualMachine.prototype.stopAll = function () {
+    this.runtime.stopAll();
+};
+
+/**
+ * Get data for playground. Data comes back in an emitted event.
+ */
+VirtualMachine.prototype.getPlaygroundData = function () {
+    this.emit('playgroundData', {
+        blocks: this.blocks,
+        threads: this.runtime.threads
+    });
+};
+
+/*
+ * Worker handlers: for all public methods available above,
+ * we must also provide a message handler in case the VM is run
+ * from a worker environment.
+ */
+if (ENV_WORKER) {
+    self.vmInstance = new VirtualMachine();
+    self.onmessage = function (e) {
+        var messageData = e.data;
+        switch (messageData.method) {
+        case 'start':
+            self.vmInstance.runtime.start();
+            break;
+        case 'greenFlag':
+            self.vmInstance.runtime.greenFlag();
+            break;
+        case 'stopAll':
+            self.vmInstance.runtime.stopAll();
+            break;
+        case 'blockListener':
+            self.vmInstance.blockListener(messageData.args);
+            break;
+        case 'flyoutBlockListener':
+            self.vmInstance.flyoutBlockListener(messageData.args);
+            break;
+        case 'getPlaygroundData':
+            self.postMessage({
+                method: 'playgroundData',
+                blocks: self.vmInstance.blocks,
+                threads: self.vmInstance.runtime.threads
+            });
+            break;
+        default:
+            throw 'Unknown method' + messageData.method;
+        }
+    };
+    // Bind runtime's emitted events to postmessages.
+    self.vmInstance.runtime.on(Runtime.STACK_GLOW_ON, function (id) {
+        self.postMessage({method: Runtime.STACK_GLOW_ON, id: id});
+    });
+    self.vmInstance.runtime.on(Runtime.STACK_GLOW_OFF, function (id) {
+        self.postMessage({method: Runtime.STACK_GLOW_OFF, id: id});
+    });
+    self.vmInstance.runtime.on(Runtime.BLOCK_GLOW_ON, function (id) {
+        self.postMessage({method: Runtime.BLOCK_GLOW_ON, id: id});
+    });
+    self.vmInstance.runtime.on(Runtime.BLOCK_GLOW_OFF, function (id) {
+        self.postMessage({method: Runtime.BLOCK_GLOW_OFF, id: id});
+    });
+}
+
 /**
  * Export and bind to `window`
  */

src/worker.js

@@ -0,0 +1,70 @@
+var EventEmitter = require('events');
+var util = require('util');
+
+function VirtualMachine () {
+    if (!window.Worker) {
+        console.error('WebWorkers not supported in this environment.' +
+            ' Please use the non-worker version (vm.js or vm.min.js).');
+        return;
+    }
+    var instance = this;
+    EventEmitter.call(instance);
+    instance.vmWorker = new Worker('../vm.js');
+
+    // onmessage calls are converted into emitted events.
+    instance.vmWorker.onmessage = function (e) {
+        instance.emit(e.data.method, e.data);
+    };
+
+    instance.blockListener = function (e) {
+        // Messages from Blockly are not serializable by default.
+        // Pull out the necessary, serializable components to pass across.
+        var serializableE = {
+            blockId: e.blockId,
+            element: e.element,
+            type: e.type,
+            name: e.name,
+            newValue: e.newValue,
+            oldParentId: e.oldParentId,
+            oldInputName: e.oldInputName,
+            newParentId: e.newParentId,
+            newInputName: e.newInputName,
+            xml: {
+                outerHTML: (e.xml) ? e.xml.outerHTML : null
+            }
+        };
+        instance.vmWorker.postMessage({
+            method: 'blockListener',
+            args: serializableE
+        });
+    };
+}
+
+/**
+ * Inherit from EventEmitter
+ */
+util.inherits(VirtualMachine, EventEmitter);
+
+// For documentation, please see index.js.
+// These mirror the functionality provided there, with the worker wrapper.
+VirtualMachine.prototype.getPlaygroundData = function () {
+    this.vmWorker.postMessage({method: 'getPlaygroundData'});
+};
+
+VirtualMachine.prototype.start = function () {
+    this.vmWorker.postMessage({method: 'start'});
+};
+
+VirtualMachine.prototype.greenFlag = function () {
+    this.vmWorker.postMessage({method: 'greenFlag'});
+};
+
+VirtualMachine.prototype.stopAll = function () {
+    this.vmWorker.postMessage({method: 'stopAll'});
+};
+
+/**
+ * Export and bind to `window`
+ */
+module.exports = VirtualMachine;
+if (typeof window !== 'undefined') window.VirtualMachine = module.exports;

webpack.config.js

@@ -3,7 +3,8 @@ var webpack = require('webpack');
 module.exports = {
     entry: {
         'vm': './src/index.js',
-        'vm.min': './src/index.js'
+        'vm.min': './src/index.js',
+        'vm.worker': './src/worker.js'
     },
     output: {
         path: __dirname,