python网络编程之sse

服务端：

from fastapi import FastAPI
from fastapi.responses import StreamingResponse
from fastapi.middleware.cors import CORSMiddleware
import time

app = FastAPI()

# 允许所有来源的跨域请求
app.add_middleware(
    CORSMiddleware,
    allow_origins=["*"],  # 允许所有来源
    allow_credentials=True,
    allow_methods=["*"],   # 允许所有HTTP方法
    allow_headers=["*"]    # 允许所有请求头
)

def generate_stream():
    for i in range(1, 11):
        yield f"data: Message {i}\n\n"
        time.sleep(1)

@app.get("/stream")
async def stream():
    return StreamingResponse(generate_stream(), media_type="text/event-stream")


#uvicorn sse_server:app --port 1090 --reload

客户端：

import requests
from requests.auth import HTTPBasicAuth
 
# 定义事件流客户端类
class EventStreamClient:
    def __init__(self, url, username=None, password=None):
        self.url = url
        self.session = requests.Session()
        if username and password:
            self.session.auth = HTTPBasicAuth(username, password)
 
    def connect(self):
        # 使用requests.Session来保持连接
        self.response = self.session.get(self.url, stream=True)
        self.response.raise_for_status()  # 检查是否连接成功
 
    def events(self):
        # 生成器：逐行读取响应内容并逐一生成事件
        for line in self.response.iter_lines():
            if line:
                yield line.decode('utf-8').rstrip()  # 去掉行尾的换行符
 
    def close(self):
        # 关闭会话
        self.session.close()
 
# 使用示例
url = 'http://127.0.0.1:1090/stream'  # 替换为实际的事件流URL
client = EventStreamClient(url, username='', password='')
try:
    client.connect()
    for event in client.events():
        print(event)  # 处理接收到的每个事件
finally:
    client.close()

输出：