属性错误--尽管属性被赋值

Question

from channels.generic.websockets import WebsocketDemultiplexer,WebsocketConsumer
from .models import TwilioCallBinding
from google.cloud import speech_v1p1beta1 as speech
from google.cloud.speech_v1 import enums,types
import json
import base64
from .SpeechClientBridge import SpeechClientBridge


class MediaStreamConsumer(WebsocketConsumer):

    config = types.RecognitionConfig(
                                   encoding=enums.RecognitionConfig.AudioEncoding.MULAW,
                                   sample_rate_hertz=8000,
                                   language_code='en-US'
                                 )

    streaming_config = types.StreamingRecognitionConfig(config=config,interim_results=True)

    def on_transcription_response(response):
        if not response.results:
            return

        result = response.results[0]
        if not result.alternatives:
            return

        transcription = result.alternatives[0].transcript
        print("Transcription: " + transcription)

    def connect(self, message, **kwargs):
        self.message.reply_channel.send({"accept": True})
        self.bridge = SpeechClientBridge(MediaStreamConsumer.streaming_config,
                                         MediaStreamConsumer.on_transcription_response)

    
        print("****************************************")

    def raw_receive(self, message, **kwargs):
        data = json.loads(message['text'])

        if data["event"] in ("connected", "start"):
            print(f"Media WS: Received event '{data['event']}': {message}")
        
        if data["event"] == "media":
            media = data["media"]
            chunk = base64.b64decode(media["payload"])

            self.bridge.add_request(chunk)

        if data["event"] == "stop":
            print(f"Media WS: Received event 'stop': {message}")
            print("Stopping...")

    def disconnect(self, message, **kwargs):
        self.bridge.terminate()

在消息接收和断开事件上，我得到了相同的错误。

AttributeError: 'MediaStreamConsumer' object has no attribute 'bridge'

我已在connect事件中分配了桥属性

def connect(self, message, **kwargs):
    self.message.reply_channel.send({"accept": True})
    self.bridge = SpeechClientBridge(MediaStreamConsumer.streaming_config,
                                         MediaStreamConsumer.on_transcription_response)

那我为什么要得到AttributeError呢？

编辑:我添加了print("*****************************")来检查是否自动调用connect方法。

做改变后的追踪。

[2020/10/28 21:27:43] HTTP POST /call-application/media-stream/ 200 [0.04, 127.0.0.1:38000]
[2020/10/28 21:27:44] WebSocket HANDSHAKING /websockets/livecallstream/ [127.0.0.1:38002]
****************************************
[2020/10/28 21:27:44] WebSocket CONNECT /websockets/livecallstream/ [127.0.0.1:38002]
Media WS: Received event 'connected': <channels.message.Message object at 0x7f579c0506a0>
Media WS: Received event 'start': <channels.message.Message object at 0x7f579c067518>
2020-10-28 21:27:44,714 - ERROR - worker - Error processing message with consumer datasleek_twilio.consumers.MediaStreamConsumer:
Traceback (most recent call last):
  File "/home/datasleek/trackervenv/lib/python3.6/site-packages/channels/worker.py", line 119, in run
    consumer(message, **kwargs)
  File "/home/datasleek/trackervenv/lib/python3.6/site-packages/channels/generic/base.py", line 32, in __init__
    self.dispatch(message, **kwargs)
  File "/home/datasleek/trackervenv/lib/python3.6/site-packages/channels/generic/base.py", line 70, in dispatch
    return self.get_handler(message, **kwargs)(message, **kwargs)
  File "/home/datasleek/tracker/datasleek_twilio/consumers.py", line 62, in raw_receive
    self.bridge.add_request(chunk)
AttributeError: 'MediaStreamConsumer' object has no attribute 'bridge'
2020-10-28 21:27:44,735 - ERROR - worker - Error processing message with consumer datasleek_twilio.consumers.MediaStreamConsumer:
Traceback (most recent call last):
  File "/home/datasleek/trackervenv/lib/python3.6/site-packages/channels/worker.py", line 119, in run
    consumer(message, **kwargs)
  File "/home/datasleek/trackervenv/lib/python3.6/site-packages/channels/generic/base.py", line 32, in __init__
    self.dispatch(message, **kwargs)
  File "/home/datasleek/trackervenv/lib/python3.6/site-packages/channels/generic/base.py", line 70, in dispatch
    return self.get_handler(message, **kwargs)(message, **kwargs)
  File "/home/datasleek/tracker/datasleek_twilio/consumers.py", line 62, in raw_receive
    self.bridge.add_request(chunk)
AttributeError: 'MediaStreamConsumer' object has no attribute 'bridge'

Answer 1

正如@Carcigenicate和@AzyCrw4282 4282在注释中提到的那样，connect不是自动调用的。尽管我仍然不确定websockets如何连接，如果没有自动调用connect，因为我可以看到消息来了。无论如何，我做了以下更改，并在进行这些更改后，在控制台中看到了的转录。。

config = types.RecognitionConfig(
                                   encoding=enums.RecognitionConfig.AudioEncoding.MULAW,
                                   sample_rate_hertz=8000,
                                   language_code='en-US'
                                 )

streaming_config = types.StreamingRecognitionConfig(config=config,interim_results=True)


def on_transcription_response(response):
    if not response.results:
        return

    result = response.results[0]
    if not result.alternatives:
        return

    transcription = result.alternatives[0].transcript
    print("Transcription: " + transcription)


bridge = None

def set_bridge():
    global bridge

    if bridge is None:
        bridge = SpeechClientBridge(streaming_config,on_transcription_response)


class MediaStreamConsumer(WebsocketConsumer):

    def connect(self, message, **kwargs):
        self.message.reply_channel.send({"accept": True})


    def raw_receive(self, message, **kwargs):
        set_bridge()

        data = json.loads(message['text'])

        if data["event"] in ("connected", "start"):
            print(f"Media WS: Received event '{data['event']}': {message}")
        
        if data["event"] == "media":
            media = data["media"]
            chunk = base64.b64decode(media["payload"])

            bridge.add_request(chunk)
   
        if data["event"] == "stop":
            print(f"Media WS: Received event 'stop': {message}")
            print("Stopping...")


    def disconnect(self, message, **kwargs):
        bridge.terminate()