带有高速公路的 websocket 中继 python

websocket relay with Autobahn python

我正在尝试使用 Autobahn python 构建一个 websocket 服务器,它充当 IBM Watson 文本到语音服务的中间人或中继。我已经设法通过使用队列从客户端接收流音频并将其转发到 Watson,并且我正在从 Watson 接收回转录假设作为 JSON 数据到我的服务器,但我不确定如何将 JSON 数据转发给客户端。似乎 Watson 转录侧回调和 Autobahn 客户端回调是独立存在的,我无法从一个回调中调用另一个回调中的例程,也无法从另一个回调中的一个回调中访问数据。

我需要设置某种共享短信队列吗?我确信它应该很简单,但我认为问题可能是我对“self”关键字缺乏理解,它似乎将两个例程隔离开来。也将感谢任何有关理解“自我”的资源。

# For Watson
from ibm_watson import SpeechToTextV1
from ibm_watson.websocket import RecognizeCallback, AudioSource
from threading import Thread
from ibm_cloud_sdk_core.authenticators import IAMAuthenticator
# For Autobahn
from autobahn.twisted.websocket import WebSocketServerProtocol, \
    WebSocketServerFactory
from twisted.internet import reactor

try:
    from Queue import Queue, Full
except ImportError:
    from queue import Queue, Full

###############################################
#### Initalize queue to store the recordings ##
###############################################
CHUNK = 1024
BUF_MAX_SIZE = CHUNK * 10
# Buffer to store audio
q = Queue(maxsize=int(round(BUF_MAX_SIZE / CHUNK)))
# Create an instance of AudioSource
audio_source = AudioSource(q, True, True)

###############################################
#### Prepare Speech to Text Service ########
###############################################

# initialize speech to text service
authenticator = IAMAuthenticator('secretapikeycanttellyou')
speech_to_text = SpeechToTextV1(authenticator=authenticator)

# define callback for the speech to text service
class MyRecognizeCallback(RecognizeCallback):
    def __init__(self):
        RecognizeCallback.__init__(self)

    def on_transcription(self, transcript):
        print(transcript)

    def on_connected(self):
        print('Connection was successful')

    def on_error(self, error):
        print('Error received: {}'.format(error))

    def on_inactivity_timeout(self, error):
        print('Inactivity timeout: {}'.format(error))

    def on_listening(self):
        print('Service is listening')

    def on_hypothesis(self, hypothesis):
        print(hypothesis)
        #self.sendMessage(hypothesis, isBinary = false)
        # HOW TO FORWARD THIS TO CLIENT?

    def on_data(self, data):
        print(data)
        #self.sendMessage(data, isBinary = false)
        # HOW TO FORWARD THIS TO CLIENT?

    def on_close(self):
        print("Connection closed")

# define callback for client-side websocket in Autobahn
class MyServerProtocol(WebSocketServerProtocol):

    def onConnect(self, request):
        print("Client connecting: {0}".format(request.peer))

    def onOpen(self):
        print("WebSocket connection open.")
        recognize_thread = Thread(target=recognize_using_weboscket, args=())
        recognize_thread.daemon = True
        recognize_thread.start()

    def onMessage(self, payload, isBinary):
        if isBinary:
            # put audio in queue
            q.put(payload)
        else:
            print("Text message received: {0}".format(payload.decode('utf8')))

        # echo back message verbatim
        self.sendMessage(payload, isBinary)
    
    def onClose(self, wasClean, code, reason):
        print("WebSocket connection closed: {0}".format(reason))
        
## this function will initiate the recognize service and pass in the AudioSource
def recognize_using_weboscket(*args):
    mycallback = MyRecognizeCallback()
    speech_to_text.recognize_using_websocket(audio=audio_source,
                                             content_type='audio/l16; rate=16000',
                                             recognize_callback=mycallback,
                                             interim_results=True)

if __name__ == '__main__':

    factory = WebSocketServerFactory("ws://127.0.0.1:9001")
    factory.protocol = MyServerProtocol

    reactor.listenTCP(9001, factory)
    reactor.run()

看来我需要弥合 MyRecognizeCallback()MyServerProtocol() 之间的差距。也请让我知道这是否是我想要实现的目标的糟糕实现。我知道有更简单的方法来中继 websocket 数据,但我想熟悉 websocket API/ 音频流和文本消息,因为最终我想从等式中删除 Watson 并使用我自己的转录算法。

基于回答, it seems that my efforts to call MyServerProtocol().sendMessage(u"this is a message2".encode('utf8')) from main were in fact creating a new and unrelated instance of MyServerProtocol rather than piping messages into the existing connection. I was able to send new messages into the open websocket connection using the method described here

这是我的最终代码,它仍然需要一些工作,但相关的定义是 broadcast_message。还需要 'subscribe' 我自己连接到 websocket onConnect 和 'unsubscribe' onClose 才能使此方法起作用:

from ibm_watson import SpeechToTextV1
from ibm_watson.websocket import RecognizeCallback, AudioSource
from threading import Thread
from ibm_cloud_sdk_core.authenticators import IAMAuthenticator
# For autobahn
import json
from autobahn.twisted.websocket import WebSocketServerProtocol, \
    WebSocketServerFactory
from twisted.internet import reactor

try:
    from Queue import Queue, Full
except ImportError:
    from queue import Queue, Full

###############################################
#### Initalize queue to store the recordings ##
###############################################
CHUNK = 1024
# Note: It will discard if the websocket client can't consumme fast enough
# So, increase the max size as per your choice
BUF_MAX_SIZE = CHUNK * 10
# Buffer to store audio
q = Queue(maxsize=int(round(BUF_MAX_SIZE / CHUNK)))
# Create an instance of AudioSource
audio_source = AudioSource(q, True, True)

###############################################
#### Prepare Speech to Text Service ########
###############################################

# initialize speech to text service
authenticator = IAMAuthenticator('secretapikey')
speech_to_text = SpeechToTextV1(authenticator=authenticator)

# define callback for the speech to text service
class MyRecognizeCallback(RecognizeCallback):
    def __init__(self):
        RecognizeCallback.__init__(self)

    def on_transcription(self, transcript):
        # Forward to client
        MyServerProtocol.broadcast_message(transcript)

    def on_connected(self):
        print('Connection was successful')

    def on_error(self, error):
        # Forward to client
        MyServerProtocol.broadcast_message('Error received: {}'.format(error))

    def on_inactivity_timeout(self, error):
        # Forward to client
        MyServerProtocol.broadcast_message('Inactivity timeout: {}'.format(error))

    def on_listening(self):
        print('Service is listening')

    def on_hypothesis(self, hypothesis):
        # Forward to client
        MyServerProtocol.broadcast_message(hypothesis)

    def on_data(self, data):
        # Forward to client
        MyServerProtocol.broadcast_message(data)

    def on_close(self):
        print("Connection closed")
        MyServerProtocol.broadcast_message("Connection closed")

class MyServerProtocol(WebSocketServerProtocol):
    connections = list()

    def onConnect(self, request):
        print("Client connecting: {0}".format(request.peer))
        self.connections.append(self)
        # Start recognizer on connection
        recognize_thread = Thread(target=recognize_using_weboscket, args=())
        recognize_thread.daemon = True
        recognize_thread.start()

    def onOpen(self):
        print("WebSocket connection open.")

    def onMessage(self, payload, isBinary):
        if isBinary:
            # Put incoming audio into the queue
            try:
                q.put(payload)
            except Full:
                pass # discard
        else:
            print("Text message received: {0}".format(payload.decode('utf8')))

    @classmethod
    def broadcast_message(cls, data):
        payload = json.dumps(data, ensure_ascii = False).encode('utf8')
        for c in set(cls.connections):
            reactor.callFromThread(cls.sendMessage, c, payload)
      

    def onClose(self, wasClean, code, reason):
        print("WebSocket connection closed: {0}".format(reason))
        self.connections.remove(self)
  
## this function will initiate the recognize service and pass in the AudioSource
def recognize_using_weboscket(*args):
    mycallback = MyRecognizeCallback()
    speech_to_text.recognize_using_websocket(audio=audio_source,
                                            content_type='audio/l16; rate=16000',
                                            recognize_callback=mycallback,
                                            interim_results=True)

if __name__ == '__main__':

factory = WebSocketServerFactory("ws://127.0.0.1:9001")
    factory.protocol = MyServerProtocol

    reactor.listenTCP(9001, factory)
    reactor.run()