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# The Speech API has a streaming limit of 60 seconds of audio*, so keep the
# connection alive for that long, plus some more to give the API time to figure
# out the transcription.
# * https://g.co/cloud/speech/limits#content
DEADLINE_SECS = 60 * 3 +5
SPEECH_SCOPE = 'https://www.googleapis.com/auth/cloud-platform'
API_Key = '46048281b7a4cf0565742f9f290118304b460181'
#API_Key = '8d8e15db8366c421910f83f4c412ef79b0114f98'
#owm = OWM(API_Key)

def make_channel(host, port):
"""Creates a secure channel with auth credentials from the environment."""
# Grab application default credentials from the environment
credentials, _ = google.auth.default(scopes=[SPEECH_SCOPE])

# Create a secure channel using the credentials.
http_request = google.auth.transport.requests.Request()
target = '{}:{}'.format(host, port)

return google.auth.transport.grpc.secure_authorized_channel(
credentials, http_request, target)

def _audio_data_generator(buff):
"""A generator that yields all available data in the given buffer.
Args:
buff - a Queue object, where each element is a chunk of data.
Yields:
A chunk of data that is the aggregate of all chunks of data in `buff`.
The function will block until at least one data chunk is available.
"""
stop = False
while not stop:
# Use a blocking get() to ensure there's at least one chunk of data.
data = [buff.get()]

# Now consume whatever other data's still buffered.
while True:
try:
data.append(buff.get(block=False))
except queue.Empty:
break

# `None` in the buffer signals that the audio stream is closed. Yield

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