Fixed bug with not closing microphone with continuous: false, added keepMic option

Author: nfriedly

README.md

@@ -53,7 +53,10 @@ Requires[window.fetch](https://developer.mozilla.org/en-US/docs/Web/API/Fetch_AP
 
 ### `.recognizeMicrophone({token})` -> `RecognizeStream`
 
-Options: No direct options, all provided options are passed to MicrophoneStream and RecognizeStream, and WritableElementStream if `options.outputElement` is set
+Options: 
+* `keepMic`: if true, preserves the MicrophoneStream for subsequent calls, preventing additional permissions requests in Firefox
+* Other options passed to MediaElementAudioStream and RecognizeStream
+* Other options passed to WritableElementStream if `options.outputElement` is set
 
 Requires the `getUserMedia` API, so limited browser compatibility (see http://caniuse.com/#search=getusermedia) 
 Also note that Chrome requires https (with a few exceptions for localhost and such) - see https://www.chromium.org/Home/chromium-security/prefer-secure-origins-for-powerful-new-features
@@ -155,6 +158,10 @@ Accepts input from `RecognizeStream()` and friends, writes text to supplied `out
 
 ## Changelog
 
+### v0.13
+* Fixed bug where `continuous: false` didn't close the microphone at end of recognition
+* Added `keepMic` option to `recognizeMicrophone()` to prevent multiple permission popups in firefox
+
 ### v0.12
 * Added `autoPlay` option to `synthesize()`
 * Added proper parameter filtering to `synthesize()`
@@ -206,3 +213,5 @@ Accepts input from `RecognizeStream()` and friends, writes text to supplied `out
 * look for bug where single-word final results may omit word confidence (possibly due to FormatStream?)
 * fix bug where TimingStream shows words slightly before they're spoken
 * automatically turn on objectMode when required by other options (timing, confidence, etc.
+* support jquery objects for element and targetElement
+* add a way to keep the mic stream so the user isn't repeatedly prompted in firefox

dist/watson-speech.js

@@ -23,6 +23,8 @@ var FormatStream = require('./format-stream.js');
 var assign = require('object.assign/polyfill')();
 var WritableElementStream = require('./writable-element-stream');
 
+var preservedMicStream;
+
 /**
  * @module watson-speech/speech-to-text/recognize-microphone
  */
@@ -34,6 +36,7 @@ var WritableElementStream = require('./writable-element-stream');
  * @param {Object} options - Also passed to {MediaElementAudioStream} and to {RecognizeStream}
  * @param {String} options.token - Auth Token - see https://github.com/watson-developer-cloud/node-sdk#authorization
  * @param {Boolean} [options.format=true] - pipe the text through a {FormatStream} which performs light formatting
+ * @param {Boolean} [options.keepMicrophone=false] - keeps an internal reference to the microphone stream to reuse in subsequent calls (prevents multiple permissions dialogs in firefox)
  * @param {String|DOMElement} [options.outputElement] pipe the text to a WriteableElementStream targeting the specified element. Also defaults objectMode to true to enable interim results.
  *
  * @returns {RecognizeStream}
@@ -56,17 +59,46 @@ module.exports = function recognizeMicrophone(options) {
 
   var recognizeStream = new RecognizeStream(rsOpts);
 
-
-  getUserMedia({video: false, audio: true}).then(function(mic) {
-    var micStream = new MicrophoneStream(mic, {
-      objectMode: true,
-      bufferSize: options.bufferSize
+  var keepMic = options.keepMicrophone;
+  var getMicStream;
+  if (keepMic && preservedMicStream) {
+    getMicStream = Promise.resolve(preservedMicStream);
+  } else {
+    getMicStream = getUserMedia({video: false, audio: true}).then(function (mic) {
+      var micStream = new MicrophoneStream(mic, {
+        objectMode: true,
+        bufferSize: options.bufferSize
+      });
+      if (keepMic) {
+        preservedMicStream = micStream;
+      }
+      return Promise.resolve(micStream);
     });
+  }
+
+  getMicStream.then(function(micStream) {
+    var l16Stream = new L16({writableObjectMode: true});
+
     micStream
-      .pipe(new L16({writableObjectMode: true}))
+      .pipe(l16Stream)
       .pipe(recognizeStream);
 
-    recognizeStream.on('stop', micStream.stop.bind(micStream));
+    function end() {
+      micStream.unpipe(l16Stream);
+      l16Stream.end();
+    }
+    // trigger on both stop and end events:
+    // stop will not fire when a stream ends due to a timeout or having continuous: false
+    // but when stop does fire, we want to honor it immediately
+    // end will always fire, but it may take a few moments after stop
+    if (keepMic) {
+      recognizeStream.on('end', end);
+      recognizeStream.on('stop', end);
+    } else {
+      recognizeStream.on('end', micStream.stop.bind(micStream));
+      recognizeStream.on('stop', micStream.stop.bind(micStream));
+    }
+
   }).catch(recognizeStream.emit.bind(recognizeStream, 'error'));
 
 

speech-to-text/recognize-microphone.js

@@ -391,7 +391,7 @@ RecognizeStream.prototype.finish = function finish() {
   this.finished = true;
   var self = this;
   var closingMessage = {action: 'stop'};
-  if (self.socket) {
+  if (self.socket && self.socket.readyState !== self.socket.CLOSED && self.socket.readyState !== self.socket.CLOSING) {
     self.sendJSON(closingMessage);
   } else {
     this.once('connect', function () {