expose stt recognizestream transaction id

Fixes watson-developer-cloud#412

Author: nfriedly

CHANGELOG.md

@@ -1,3 +1,6 @@
+# v2.24.1
+* STT RecognizeStream now exposes Transaction ID
+
 # v2.23.1
 * Restored support for Node.js 4.0-4.4
 

speech-to-text/recognize_stream.js

@@ -259,6 +259,29 @@ RecognizeStream.prototype.stop = function() {
   this.socket.close();
 };
 
+/**
+ * Returns a Promise that resolves with Watson Transaction ID from the X-Transaction-ID header
+ *
+ * Works in Node.js but not in browsers (the W3C WebSocket API does not expose headers)
+ *
+ * @return Promise<String>
+ */
+RecognizeStream.prototype.getTransactionId = function() {
+  if (this.socket &&
+    this.socket._client &&
+    this.socket._client.response &&
+    this.socket._client.response.headers) {
+    return Promise.resolve(this.socket._client.response.headers['x-global-transaction-id']);
+  } else {
+    return new Promise((resolve, reject) => {
+      this.on('connect', () => {
+        resolve(this.socket._client.response.headers['x-global-transaction-id']);
+      });
+      this.on('error', reject);
+    });
+  }
+};
+
 // quick/dumb way to determine content type from a supported file format
 const headerToContentType = {
   fLaC: 'audio/flac',

test/integration/test.speech_to_text.js

@@ -113,35 +113,44 @@ describe('speech_to_text_integration', function() {
     speech_to_text.getModels({}, done);
   });
 
-  it('createRecognizeStream()', function(done) {
-    const recognizeStream = speech_to_text.createRecognizeStream({
-      content_type: 'audio/l16; rate=44100'
+  describe('createRecognizeStream()', () => {
+    it('transcribes audio over a websocket', function(done) {
+      const recognizeStream = speech_to_text.createRecognizeStream();
+      recognizeStream.setEncoding('utf8');
+      fs.createReadStream(path.join(__dirname, '../resources/weather.flac')).pipe(recognizeStream).on('error', done).pipe(
+        concat(function(transcription) {
+          assert.equal(typeof transcription, 'string', 'should return a string transcription');
+          assert.equal(transcription.trim(), 'thunderstorms could produce large hail isolated tornadoes and heavy rain');
+          done();
+        })
+      );
     });
-    recognizeStream.setEncoding('utf8');
-    fs.createReadStream(path.join(__dirname, '../resources/weather.flac')).pipe(recognizeStream).on('error', done).pipe(
-      concat(function(transcription) {
-        assert.equal(typeof transcription, 'string', 'should return a string transcription');
-        assert.equal(transcription.trim(), 'thunderstorms could produce large hail isolated tornadoes and heavy rain');
-        done();
-      })
-    );
-  });
 
-  it('createRecognizeStream() - no words', function(done) {
-    const recognizeStream = speech_to_text.createRecognizeStream({
-      content_type: 'audio/l16; rate=44100'
+    it('works when stream has no words', function(done) {
+      const recognizeStream = speech_to_text.createRecognizeStream({
+        content_type: 'audio/l16; rate=44100'
+      });
+      recognizeStream.setEncoding('utf8');
+      fs
+        .createReadStream(path.join(__dirname, '../resources/blank.wav'))
+        .pipe(recognizeStream)
+        .on('error', done)
+        .on('data', function(text) {
+          assert(!text, 'no text expected for an audio file with no words');
+        })
+        .on('end', done);
     });
-    recognizeStream.setEncoding('utf8');
-    fs
-      .createReadStream(path.join(__dirname, '../resources/blank.wav'))
-      .pipe(recognizeStream)
-      .on('error', done)
-      .on('data', function(text) {
-        assert(!text, 'no text expected for an audio file with no words');
-      })
-      .on('end', done);
+
+    it('exposes Transaction ID in node.js', () => {
+      const recognizeStream = speech_to_text.createRecognizeStream();
+      return fs.createReadStream(path.join(__dirname, '../resources/weather.ogg'))
+        .pipe(recognizeStream)
+        .getTransactionId()
+        .then(id => assert(id));
+    })
   });
 
+
   describe('customization', function() {
     let customization_id;