python中使用websocket进行链接与数据存储

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笔者最近在测试星火大模型的时候，他们是使用websocket 来建立对话，而且星火大模型开放的测试代码，质量上不咋地（20231030记录），还需要对websocket有一定的了解，才适合自己微调。

安装：

代码语言：javascript
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pip install websocket
pip install websocket-client

1 常见的websocket获取数据的方法

参考【python: websocket获取实时数据的几种常见链接方式】常见的两种。

1.1 第一种使用create_connection链接

需要pip install websocket-client (此方法不建议使用，链接不稳定，容易断，并且连接很耗时)

代码语言：javascript
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import time
from websocket import create_connection

url = 'wss://i.cg.net/wi/ws'

while True:  # 一直链接，直到连接上就退出循环

time.sleep(2)

try:

ws = create_connection(url)

print(ws)

break

except Exception as e:

print('连接异常：', e)

continue

while True:  # 连接上，退出第一个循环之后，此循环用于一直获取数据

ws.send('{"event":"subscribe", "channel":"btc_usdt.ticker"}')

response = ws.recv()

print(response)

1.2 第二种：WebSocketApp + run_forever的方式

代码语言：javascript
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import websocket


def on_message(ws, message):  # 服务器有数据更新时，主动推送过来的数据

print(message)


def on_error(ws, error):  # 程序报错时，就会触发on_error事件

print(error)


def on_close(ws):

print("Connection closed ……")


def on_open(ws):  # 连接到服务器之后就会触发on_open事件，这里用于send数据

req = '{"event":"subscribe", "channel":"btc_usdt.deep"}'

print(req)

ws.send(req)


if name == "main":

websocket.enableTrace(True)

ws = websocket.WebSocketApp("wss://i.cg.net/wi/ws",

on_message=on_message,

on_error=on_error,

on_close=on_close)

ws.on_open = on_open

ws.run_forever(ping_timeout=30)

第二种方式里面，run_forever其实是流式返回内容，大概可以看，流式输出的样例：

代码语言：javascript
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{"code":0,"sid":"5ebc0d6833b54909b4a51fbe75a5051a","status":0}


error: 'content'


{"code":0,"fileRefer":"{"43816997a7a44a299d0bfb7c360c5838":[2,0,1]}","sid":"5ebc0d6833b54909b4a51fbe75a5051a","status":99}


error: 'content'


{"code":0,"content":"橘","sid":"5ebc0d6833b54909b4a51fbe75a5051a","status":1}


橘{"code":0,"content":"子。","sid":"5ebc0d6833b54909b4a51fbe75a5051a","status":1}


子。{"code":0,"content":"","sid":"5ebc0d6833b54909b4a51fbe75a5051a","status":2}


closed ###

那么run_forever流式输出，正常的内容如何保存呢，进入下一章

2 针对run_forever内容保存

2.1 通过定义global变量来保存内容

参考【将Websocket数据保存到Pandas】

来看一下，文中的案例：

代码语言：javascript
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import json


import pandas as pd

import websocket


df = pd.DataFrame(columns=['foreignNotional', 'grossValue', 'homeNotional', 'price', 'side',

'size', 'symbol', 'tickDirection', 'timestamp', 'trdMatchID'])


def on_message(ws, message):

msg = json.loads(message)

print(msg)

global df

# ignore_index=True has to be provided, otherwise you'll get

# "Can only append a Series if ignore_index=True or if the Series has a name" errors

df = df.append(msg, ignore_index=True)


def on_error(ws, error):

print(error)


def on_close(ws):

print("### closed ###")


def on_open(ws):

return


if name == "main":

ws = websocket.WebSocketApp("wss://www.bitmex.com/realtime?subscribe=trade:XBTUSD",

on_open=on_open, on_message=on_message, on_error=on_error, on_close=on_close)

ws.run_forever()

其中global df是在定义全局变量df，可以在函数中把流式数据拿出来，还是很不错的

2.2 通过CallbackToIterator()来返回

在开源项目中ChuanhuChatGPT，看到了使用的方式spark.py，个人还没有尝试，只是贴在这里。

贴一下这个函数：

代码语言：javascript
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class CallbackToIterator:

def __init__(self):

self.queue = deque()

self.cond = Condition()

self.finished = False


def callback(self, result):
    with self.cond:
        self.queue.append(result)
        self.cond.notify()  # Wake up the generator.

def __iter__(self):
    return self

def __next__(self):
    with self.cond:
        # Wait for a value to be added to the queue.
        while not self.queue and not self.finished:
            self.cond.wait()
        if not self.queue:
            raise StopIteration()
        return self.queue.popleft()

def finish(self):
    with self.cond:
        self.finished = True
        self.cond.notify()  # Wake up the generator if it's waiting.



主函数截取


def get_answer_stream_iter(self):

wsParam = Ws_Param(self.appid, self.api_key, self.api_secret, self.spark_url)

websocket.enableTrace(False)

wsUrl = wsParam.create_url()

ws = websocket.WebSocketApp(

wsUrl,

on_message=self.on_message,

on_error=self.on_error,

on_close=self.on_close,

on_open=self.on_open,

)

ws.appid = self.appid

ws.domain = self.domain


# Initialize the CallbackToIterator
ws.iterator = CallbackToIterator()

# Start the WebSocket connection in a separate thread
thread.start_new_thread(
    ws.run_forever, (), {"sslopt": {"cert_reqs": ssl.CERT_NONE}}
)

# Iterate over the CallbackToIterator instance
answer = ""
total_tokens = 0
for message in ws.iterator:
    data = json.loads(message)
    code = data["header"]["code"]
    if code != 0:
        ws.close()
        raise Exception(f"请求错误: {code}, {data}")
    else:
        choices = data["payload"]["choices"]
        status = choices["status"]
        content = choices["text"][0]["content"]
        if "usage" in data["payload"]:
            total_tokens = data["payload"]["usage"]["text"]["total_tokens"]
        answer += content
        if status == 2:
            ws.iterator.finish()  # Finish the iterator when the status is 2
            ws.close()
        yield answer, total_tokens</code></pre></div></div><p>截取了部分代码，这里先是定义<code>ws.iterator = CallbackToIterator()</code>然后通过迭代从<code>for message in ws.iterator:</code>拿出数据，看上去也是可行的</p>
#python#websocket#连接#数据#数据存储