blockly protocol refactor / fixes

package.json

@@ -8,7 +8,7 @@
     "start": "ionic-app-scripts serve",
     "clean": "ionic-app-scripts clean",
     "build": "ionic-app-scripts build --prod",
-    "android:build": "ionic cordova build --release --prod android",
+    "android:build": "npm run clean && ionic cordova build --release --prod android",
     "android:build:debug": "ionic cordova build android",
     "android:deploy": "adb install -r platforms/android/app/build/outputs/apk/debug/app-debug.apk",
     "android:start": "adb shell am force-stop de.sensebox.blockly; adb shell am start -n de.sensebox.blockly/de.sensebox.blockly.MainActivity; sleep 5; adb logcat | grep -F \"`adb shell ps | grep de.sensebox.blockly | awk -F' ' '{print $2}'`\"",

src/pages/blockly/blockly_protocol.ts

@@ -8,10 +8,16 @@ import { LoggingProvider } from '../../providers/logging/logging';
  */
 
 export class BlocklyMessageProtocol {
-  ready: Promise<void>
+  // resolve ready promise once the blocklyFrame is ready
+  ready = new Promise(resolve => {
+    window.addEventListener('message', (ev: IframePostMessageEvent) => {
+      // @HACK @FIXME: timeout is required, as blockly resolves some async functions
+      // after firing the `ready` event..
+      if (ev.data.type === 'ready') setTimeout(resolve, 300)
+    })
+  })
 
-  // defines the expected response type for each request type
-  private reqResPatterns: BlocklyReqPatterns = {
+  static reqResPatterns: BlocklyReqPatterns = {
     'getSketch': 'sketch',
     'getXml': 'xml',
     'setXml': null,
@@ -26,20 +32,10 @@ export class BlocklyMessageProtocol {
       else
         this.log.debug(`received ${ev.data.type} message from blockly`, { message: ev.data })
     })
-
-    // resolve ready promise once the blocklyFrame is ready
-    this.ready = new Promise(resolve => {
-      window.addEventListener('message', (ev: IframePostMessageEvent) => {
-        // @HACK @FIXME: timeout is required, as blockly resolves some async functions
-        // after firing the `ready` event..
-        if (ev.data.type === 'ready') setTimeout(resolve, 300)
-      })
-    })
   }
 
   toggleView() { this.sendRequest({ type: 'toggleView' }) }
   setXml(data: string) { this.sendRequest({ type: 'setXml', data }) }
-
   getXml() { return this.sendRequest({ type: 'getXml' }) }
   getSketch() { return this.sendRequest({ type: 'getSketch' }) }
 
@@ -48,13 +44,13 @@ export class BlocklyMessageProtocol {
 
     if (
       !this.blocklyFrame ||
-      !this.blocklyFrame.nativeElement &&
+      !this.blocklyFrame.nativeElement ||
       !this.blocklyFrame.nativeElement.contentWindow
     ) {
-      throw Error('cannot access blockly frame')
+      throw new Error('cannot access blockly frame')
     }
 
-    const expectResponse = this.reqResPatterns[req.type]
+    const expectResponse = BlocklyMessageProtocol.reqResPatterns[req.type]
     this.log.debug(`sending ${req.type} message to blockly, expecting response: ${expectResponse}`, { message: req })
 
     if (!expectResponse)
@@ -65,14 +61,14 @@ export class BlocklyMessageProtocol {
       const resHandler = ({ data: res }: IframePostMessageEvent) => {
         if (expectResponse !== res.type) return
         window.removeEventListener('message', resHandler)
-        if (expectResponse === 'error') reject(res.data)
+        if (res.type === 'error') reject(res.data)
         else resolve(res.data)
       }
       // TODO: promise reject after timeout?
       window.addEventListener('message', resHandler)
     })
 
-    // send message after registering the subscribe handler!
+    // send message *after* registering the response handler!
     this.blocklyFrame.nativeElement.contentWindow.postMessage(req, '*')
     return resPromise
   }