Trouble passing string variable to return data from python function to be used globally anywhere in a python script or program - EDITED for clarity

问题

I am editing my question to reflect the issue I am having in my application.

I am trying to take a streamed audio and convert it to text using Google text to speech. Then pass that that text as input to a conversation not on Watson. Watson then returns its answer.

The latter half works great.

The issue I am having is that I can't get the script to pass the text from the recorded speech to the Watson service I created.

I don't get an error, I just get nothing. The mic is working (I tested it with another script). The program actually indicates I could understand my response (no text I assume). Here is my code

import os
import watson_developer_cloud

import speech_recognition as sr
from gtts import gTTS
import watson_developer_cloud
import time

# Set up Assistant service.
service = watson_developer_cloud.AssistantV1(
  #username = 'USERNAME', # replace with service username
  #password = 'PASSWORD', # replace with service password

  iam_api_key = 'xxxxxxxxxx', # replace with service username
  url = 'xxxxxxxxxx', # replace with service password
  version = 'xxxxxxxxxx'
)
workspace_id = 'xxxxxxxxxxxxxx' # replace with workspace ID

def getaudiodevices():
    devices = os.popen("arecord -l")
    device_string = devices.read()
    device_string = device_string.split("\n")
    for line in device_string:
        if line.find("card") != -1:
            print("hw:" + line[line.find("card") + 5] + "," + line[line.find("device") + 7])

def speak(audiostring):
    print(audiostring)
    tts = gTTS(text=audiostring, lang='en')
    tts.save('audio.mp3')
    os.system('mpg321 audio.mp3')

def recordaudio():
    # Record Audio
    r = sr.Recognizer()
    with sr.Microphone(0) as source:
        print("Say something!")
        audio = r.listen(source,phrase_time_limit=10)
    # Speech recognition ******
    data = " "
    try:
        data = r.recognize_google(audio)
        print("You said: " + data)
    except sr.UnknownValueError:
        print("Google Speech Recognition could not understand audio")
    except sr.RequestError as e:
        print("Could not request results from Google Speech Recognition service; {0}".format(e))

    return data

# Initialize with empty value to start the conversation.
user_input = ''
context = {}
current_action = ''

# Main input/output loop
while current_action != 'end_conversation':

  # Send message to Assistant service.
  response = service.message(
    workspace_id = workspace_id,
    input = {
      'text': user_input
    },
    context = context
  )

  # Print the output from dialog, if any.
  if response['output']['text']:
    print(response['output']['text'][0])
    speak(response['output']['text'][0])

  # Update the stored context with the latest received from the dialog.
  context = response['context']
  # Check for action flags sent by the dialog.
  if 'action' in response['output']:
    current_action = response['output']['action']
  # User asked what time it is, so we output the local system time.
  if current_action == 'display_time':
    print('The current time is ' + time.strftime('%I:%M:%S %p') + '.')
    speak('The current time is ' + time.strftime('%I:%M:%S %p') + '.')
  # If we're not done, prompt for next round of input.
  if current_action != 'end_conversation':
    user_input = input('>> ')

Note: currently I can write the speech from keyboard and it works. I want the user input to come from the text generated from the transcribes audio using Google Text to speech. I need to get the data from the recorded audio into the main part of my python script where it is communicating with the Watson service.

Can someone help me figure this out?

回答1:

There are some subtleties that are best explored through examples, which I will provide below. An important keyword is 'global'. You can use the keyword 'global' inside a function to ensure that Python knows you want to work with the global variable with that name, and not declare a local variable.

Lists and other collections are interesting, because Python can understand when you are trying to modify an existing collection rather than declare a new one. An example of this is included in the demo code.

# These are global variables accessible anywhere in the script.
# They do not belong to any function or class.
my_string = ""
my_list = [1]


def a():
    return "a"


def b():
    my_string = "b" # this *is not* the global my_string


def c():
    global my_string
    my_string = "c" # this *is* the global my_string


def d():
    my_list = [7] # this *is not* the global my_list


def e():
    my_list[0] = 4 # this *is* the global my_list


def f():
    global my_list
    my_list = [1, 2, 3] # this *is* the global my_list


my_string = a()
print(my_string) # my_string has been assigned "a"


b()
print(my_string) # my_string is still "a"


c()
print(my_string) # my_string is now "c"


d()
print(my_list) # my_list is still [1]


e()
print(my_list) # my_list is now [7]


f()
print(my_list) # my_list is now [1, 2, 3]

回答2:

So, the solution by @Denziloe was correct with a few more additions.

In the main I put a whole loop for while the microphone is active, I then initiated user input to start the service connection. Then I put in another loop with data = recordaudio() and set the user input to data.

It now works.

Thanks everyone.

来源：https://stackoverflow.com/questions/52030377/trouble-passing-string-variable-to-return-data-from-python-function-to-be-used-g