Adds streaming snippet for howto (#881)

Author: gguuss

speech/cloud-client/transcribe_streaming.py

@@ -0,0 +1,54 @@
+#!/usr/bin/env python
+
+# Copyright 2017 Google Inc. All Rights Reserved.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+"""Google Cloud Speech API sample application using the streaming API.
+
+Example usage:
+    python transcribe_streaming.py resources/audio.raw
+"""
+
+# [START import_libraries]
+import argparse
+import io
+# [END import_libraries]
+
+
+def transcribe_streaming(stream_file):
+    """Streams transcription of the given audio file."""
+    from google.cloud import speech
+    speech_client = speech.Client()
+
+    with io.open(stream_file, 'rb') as audio_file:
+        audio_sample = speech_client.sample(
+            stream=audio_file,
+            encoding=speech.encoding.Encoding.LINEAR16,
+            sample_rate=16000)
+        alternatives = audio_sample.streaming_recognize()
+
+        for alternative in alternatives:
+            print('Finished: {}'.format(alternative.is_final))
+            print('Stability: {}'.format(alternative.stability))
+            print('Transcript: {}'.format(alternative.confidence))
+            print('Transcript: {}'.format(alternative.transcript))
+
+
+if __name__ == '__main__':
+    parser = argparse.ArgumentParser(
+        description=__doc__,
+        formatter_class=argparse.RawDescriptionHelpFormatter)
+    parser.add_argument('stream', help='File to stream to the API')
+    args = parser.parse_args()
+    transcribe_streaming(args.stream)

speech/cloud-client/transcribe_streaming_test.py

@@ -0,0 +1,23 @@
+# Copyright 2017, Google, Inc.
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#    http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+import re
+
+import transcribe_streaming
+
+
+def test_transcribe_streaming(resource, capsys):
+    transcribe_streaming.transcribe_streaming(resource('audio.raw'))
+    out, err = capsys.readouterr()
+
+    assert re.search(r'how old is the Brooklyn Bridge', out, re.DOTALL | re.I)