使用fastapi搭建ChatGPT对话后台

使用fastapi搭建ChatGPT对话后台

参考资料:使用fastapi搭建ChatGPT对话后台

效果:在本地构建网页达成类似chatgpt的对话效果,一个字一个字的返回生成结果

ChatGPT初步调用

python 复制代码
import os
import fastapi
import dotenv
from httpx import AsyncClient
from typing import List,Dict
dotenv.load_dotenv('./env')

# print(os.getenv('OPENAI_API_BASE'))
async def request(val: List[dict[str,str]]):
    """
    发起请求
    val: 对话内容
    """
    url = "https://xiaoai.plus/v1/chat/completions"
    headers ={
        "Content-Type": "application/json",
        "Authorization": "Bearer " + os.getenv("OPENAI_API_KEY")
    }
    params = {
        "model": "gpt-3.5-turbo",
        "messages": val, # [{"role": "user", "content": "Say this is a test!"}]
        "temperature": 0.7,
        "n": 1,
        "max_tokens": 3000,
        "stream": False
    }
    async with AsyncClient() as clinet:
        response = await clinet.post(url, headers=headers,json=params,timeout=60)
        print(response.json())

if __name__ == '__main__':
    import asyncio
    asyncio.run(request([{"role": "user", "content": "Hello!"}]))
bash 复制代码
{'id': 'chatcmpl-ABYGZNDqhtZn5igtaukBbLPWrdTPZ', 'object': 'chat.completion', 'created': 1727316691, 'model': 'gpt-3.5-turbo', 'choices': [{'index': 0, 'message': {'role': 'assistant', 'content': 'Hello! How can I assist you today?'}, 'finish_reason': 'stop'}], 'usage': {'prompt_tokens': 9, 'completion_tokens': 9, 'total_tokens': 18}, 'system_fingerprint': 'fp_808245b034'}

对回答进行解析, 这里的结果是一次性返回消息内容

bash 复制代码
{
    "id": "chatcmpl-ABYGZNDqhtZn5igtaukBbLPWrdTPZ",  # 唯一标识符,用于追踪请求
    "object": "chat.completion",  # 对象类型,表示这是一个聊天完成事件
    "created": 1727316691,  # 创建时间戳,表示响应创建的时间
    "model": "gpt-3.5-turbo",  # 使用的模型名称
    "choices": [  # 选择列表,可能包含多个回复,这里只有一个
        {
            "index": 0,  # 当前选择的索引
            "message": {  # 选择的消息内容
                "role": "assistant",  # 消息角色,这里是助手
                "content": "Hello! How can I assist you today?"  # 消息内容
            },
            "finish_reason": "stop"  # 完成原因,这里是"stop",表示模型决定停止生成更多内容
        }
    ],
    "usage": {  # 使用情况,包括token使用情况
        "prompt_tokens": 9,  # 提示token的数量
        "completion_tokens": 9,  # 完成token的数量
        "total_tokens": 18  # 总token的数量
    },
    "system_fingerprint": "fp_808245b034"  # 系统指纹,用于识别请求的系统环境
}

流式调用ChatGPT

修改上述代码中的"stream": Trueprint(response.text)部分

python 复制代码
import os
import fastapi
import dotenv
from httpx import AsyncClient
from typing import List,Dict
dotenv.load_dotenv('./env')

# print(os.getenv('OPENAI_API_BASE'))
async def request(val: List[dict[str,str]]):
    """
    发起请求
    val: 对话内容
    """
    url = "https://xiaoai.plus/v1/chat/completions"
    headers ={
        "Content-Type": "application/json",
        "Authorization": "Bearer " + os.getenv("OPENAI_API_KEY")
    }
    params = {
        "model": "gpt-3.5-turbo",
        "messages": val, # [{"role": "user", "content": "Say this is a test!"}]
        "temperature": 0.7,
        "n": 1,
        "max_tokens": 3000,
        "stream": True
    }
    async with AsyncClient() as clinet:
        response = await clinet.post(url, headers=headers,json=params,timeout=60)
        print(response.text)

if __name__ == '__main__':
    import asyncio
    asyncio.run(request([{"role": "user", "content": "Hello!"}]))

可以看到GPT的结果是一个词一个词的返回的

bash 复制代码
data: {"id":"chatcmpl-ABYJD1L22azzx2PK9IyqCaw2RrC7J","object":"chat.completion.chunk","created":1727316855,"model":"gpt-3.5-turbo","system_fingerprint":"fp_808245b034","choices":[{"index":0,"delta":{"role":"assistant","content":""},"finish_reason":null}]}

data: {"id":"chatcmpl-ABYJD1L22azzx2PK9IyqCaw2RrC7J","object":"chat.completion.chunk","created":1727316855,"model":"gpt-3.5-turbo","system_fingerprint":"fp_808245b034","choices":[{"index":0,"delta":{"content":"Hello"},"finish_reason":null}]}

data: {"id":"chatcmpl-ABYJD1L22azzx2PK9IyqCaw2RrC7J","object":"chat.completion.chunk","created":1727316855,"model":"gpt-3.5-turbo","system_fingerprint":"fp_808245b034","choices":[{"index":0,"delta":{"content":"!"},"finish_reason":null}]}

data: {"id":"chatcmpl-ABYJD1L22azzx2PK9IyqCaw2RrC7J","object":"chat.completion.chunk","created":1727316855,"model":"gpt-3.5-turbo","system_fingerprint":"fp_808245b034","choices":[{"index":0,"delta":{"content":" How"},"finish_reason":null}]}

data: {"id":"chatcmpl-ABYJD1L22azzx2PK9IyqCaw2RrC7J","object":"chat.completion.chunk","created":1727316855,"model":"gpt-3.5-turbo","system_fingerprint":"fp_808245b034","choices":[{"index":0,"delta":{"content":" can"},"finish_reason":null}]}

data: {"id":"chatcmpl-ABYJD1L22azzx2PK9IyqCaw2RrC7J","object":"chat.completion.chunk","created":1727316855,"model":"gpt-3.5-turbo","system_fingerprint":"fp_808245b034","choices":[{"index":0,"delta":{"content":" I"},"finish_reason":null}]}

data: {"id":"chatcmpl-ABYJD1L22azzx2PK9IyqCaw2RrC7J","object":"chat.completion.chunk","created":1727316855,"model":"gpt-3.5-turbo","system_fingerprint":"fp_808245b034","choices":[{"index":0,"delta":{"content":" assist"},"finish_reason":null}]}

data: {"id":"chatcmpl-ABYJD1L22azzx2PK9IyqCaw2RrC7J","object":"chat.completion.chunk","created":1727316855,"model":"gpt-3.5-turbo","system_fingerprint":"fp_808245b034","choices":[{"index":0,"delta":{"content":" you"},"finish_reason":null}]}

data: {"id":"chatcmpl-ABYJD1L22azzx2PK9IyqCaw2RrC7J","object":"chat.completion.chunk","created":1727316855,"model":"gpt-3.5-turbo","system_fingerprint":"fp_808245b034","choices":[{"index":0,"delta":{"content":" today"},"finish_reason":null}]}

data: {"id":"chatcmpl-ABYJD1L22azzx2PK9IyqCaw2RrC7J","object":"chat.completion.chunk","created":1727316855,"model":"gpt-3.5-turbo","system_fingerprint":"fp_808245b034","choices":[{"index":0,"delta":{"content":"?"},"finish_reason":null}]}

data: {"id":"chatcmpl-ABYJD1L22azzx2PK9IyqCaw2RrC7J","object":"chat.completion.chunk","created":1727316855,"model":"gpt-3.5-turbo","system_fingerprint":"fp_808245b034","choices":[{"index":0,"delta":{},"finish_reason":"stop"}]}

data: [DONE]

逐行处理流式响应

修改相应的代码

python 复制代码
    # async with AsyncClient() as clinet:
    #     response = await clinet.post(url, headers=headers,json=params,timeout=60)
    #     print(response.text)
    async with AsyncClient() as clinet:
        async with clinet.stream("POST", url, headers=headers, json=params, timeout=60) as response:
            async for line in response.aiter_lines():
                print(line)
python 复制代码
import os
import fastapi
import dotenv
from httpx import AsyncClient
from typing import List,Dict
import json
from collections import defaultdict
dotenv.load_dotenv('./env')

# print(os.getenv('OPENAI_API_BASE'))
async def request(val: List[dict[str,str]]):
    """
    发起请求
    val: 对话内容
    """
    url = "https://xiaoai.plus/v1/chat/completions"
    headers ={
        "Content-Type": "application/json",
        "Authorization": "Bearer " + os.getenv("OPENAI_API_KEY")
    }
    params = {
        "model": "gpt-3.5-turbo",
        "messages": val, # [{"role": "user", "content": "Say this is a test!"}]
        "temperature": 0.7,
        "n": 1,
        "max_tokens": 3000,
        "stream": True
    }
    # async with AsyncClient() as clinet:
    #     response = await clinet.post(url, headers=headers,json=params,timeout=60)
    #     print(response.text)
    async with AsyncClient() as clinet:
        async with clinet.stream("POST", url, headers=headers, json=params, timeout=60) as response:
            async for line in response.aiter_lines():
                if line.strip() == "":
                    continue
                line = line.replace("data: ","")
                if line.strip() == "[DONE]":
                    return
                data = json.loads(line)
                if data.get("choices") is None or len(data.get("choices")) == 0 or data.get("choices")[0].get("finish_reason") is not None:
                    return
                yield data.get("choices")[0]

async def chat(inp: str):
    message = [{"role": "user", "content": inp}]
    async for i in request(message):
        print(i)
if __name__ == '__main__':
    import asyncio
    asyncio.run(chat("你好啊"))
bash 复制代码
{'index': 0, 'delta': {'role': 'assistant', 'content': ''}, 'finish_reason': None}
{'index': 0, 'delta': {'content': '你'}, 'finish_reason': None}
{'index': 0, 'delta': {'content': '好'}, 'finish_reason': None}
{'index': 0, 'delta': {'content': ','}, 'finish_reason': None}
{'index': 0, 'delta': {'content': '有'}, 'finish_reason': None}
{'index': 0, 'delta': {'content': '什'}, 'finish_reason': None}
{'index': 0, 'delta': {'content': '么'}, 'finish_reason': None}
{'index': 0, 'delta': {'content': '可以'}, 'finish_reason': None}
{'index': 0, 'delta': {'content': '帮'}, 'finish_reason': None}
{'index': 0, 'delta': {'content': '助'}, 'finish_reason': None}
{'index': 0, 'delta': {'content': '你'}, 'finish_reason': None}
{'index': 0, 'delta': {'content': '的'}, 'finish_reason': None}
{'index': 0, 'delta': {'content': '吗'}, 'finish_reason': None}
{'index': 0, 'delta': {'content': '?'}, 'finish_reason': None}

封装请求与chat方法

python 复制代码
import os
import fastapi
import dotenv
from httpx import AsyncClient
from typing import List,Dict
import json
from collections import defaultdict
dotenv.load_dotenv('./env')

# print(os.getenv('OPENAI_API_BASE'))
async def request(val: List[dict[str,str]]):
    """
    发起请求
    val: 对话内容
    """
    url = "https://xiaoai.plus/v1/chat/completions"
    headers ={
        "Content-Type": "application/json",
        "Authorization": "Bearer " + os.getenv("OPENAI_API_KEY")
    }
    params = {
        "model": "gpt-3.5-turbo",
        "messages": val, # [{"role": "user", "content": "Say this is a test!"}]
        "temperature": 0.7,
        "n": 1,
        "max_tokens": 3000,
        "stream": True
    }
    # async with AsyncClient() as clinet:
    #     response = await clinet.post(url, headers=headers,json=params,timeout=60)
    #     print(response.text)
    async with AsyncClient() as clinet:
        async with clinet.stream("POST", url, headers=headers, json=params, timeout=60) as response:
            async for line in response.aiter_lines():
                if line.strip() == "":
                    continue
                line = line.replace("data: ","")
                if line.strip() == "[DONE]":
                    return
                data = json.loads(line)
                if data.get("choices") is None or len(data.get("choices")) == 0 or data.get("choices")[0].get("delta").get("finish_reason") is not None:
                    return
                yield data.get("choices")[0]

async def chat(inp: str):
    message = [{"role": "user", "content": inp}]
    chat_msg = defaultdict(str)
    async for i in request(message):
        if i.get("delta").get("role"):
            chat_msg["role"] = i.get("delta").get("role")
        if i.get("delta").get("content"):
            chat_msg["content"] += i.get("delta").get("content")
    print(chat_msg)
if __name__ == '__main__':
    import asyncio
    asyncio.run(chat("你好啊"))
bash 复制代码
defaultdict(<class 'str'>, {'role': 'assistant', 'content': '你好!有什么我可以帮助你的吗?'}

使用fastapi进行封装

python 复制代码
import os
import fastapi
import dotenv
from httpx import AsyncClient
from typing import List,Dict
from fastapi import FastAPI, WebSocket
from fastapi.middleware.cors import CORSMiddleware

import json
from collections import defaultdict
from fastapi.responses import HTMLResponse

app = FastAPI()
dotenv.load_dotenv('./env')


# app.add_middleware(
#     CORSMiddleware,
#     allow_origins=["*"],
#     allow_credentials=True,
#     allow_methods=["*"],
#     allow_headers=["*"],
# )


@app.get("/")
async def root():
    return {"message": "Hello World"}

# print(os.getenv('OPENAI_API_BASE'))
async def request(val: List[dict[str,str]]):
    """
    发起请求
    val: 对话内容
    """
    url = "https://xiaoai.plus/v1/chat/completions"
    headers ={
        "Content-Type": "application/json",
        "Authorization": "Bearer " + os.getenv("OPENAI_API_KEY"),

    }
    params = {
        "model": "gpt-3.5-turbo",
        "messages": val, # [{"role": "user", "content": "Say this is a test!"}]
        "temperature": 0.7,
        "n": 1,
        "max_tokens": 3000,
        "stream": True
    }
    # async with AsyncClient() as clinet:
    #     response = await clinet.post(url, headers=headers,json=params,timeout=60)
    #     print(response.text)
    async with AsyncClient() as clinet:
        async with clinet.stream("POST", url, headers=headers, json=params, timeout=60) as response:
            async for line in response.aiter_lines():
                if line.strip() == "":
                    continue
                line = line.replace("data: ","")
                if line.strip() == "[DONE]":
                    return
                data = json.loads(line)
                if data.get("choices") is None or len(data.get("choices")) == 0 or data.get("choices")[0].get("delta").get("finish_reason") is not None:
                    return
                yield data.get("choices")[0]

@app.websocket("/chat")
async def chat(websocket: WebSocket):
    await websocket.accept()
    message = []
    while True:
        data = await websocket.receive_text()
        if data == "quit": 
            await websocket.close()
            break
        message.append({"role": "user", "content": data})
        chat_msg = defaultdict(str)
        async for i in request(message):
            if i.get("delta").get("role"):
                chat_msg["role"] = i.get("delta").get("role")
            if i.get("delta").get("content"):
                chat_msg["content"] += i.get("delta").get("content")
                await websocket.send_text(i.get("delta").get("content"))
        message.append(chat_msg)

if __name__ == '__main__':
    import uvicorn
    uvicorn.run("main:app", host="127.0.0.1",port=8080,reload=True)

使用html界面调用

html 复制代码
<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
<title>Titile</title>
</head>
<body>
    <p>连接状态: <span id="status">未连接</span></p>
    <p>回复消息: <span id="message"></span></p>
    <p><input id="inp"></p>
    <button type="submit" id="submit">提交</button>
<script>
    let status = document.getElementById("status")
    let message = document.getElementById("message")
    let inp = document.getElementById("inp")
    let submit = document.getElementById("submit")

    let socket = new WebSocket("ws://127.0.0.1:8080/chat")
    socket.addEventListener("open", (event)=>{
        status.innerText = "已连接"
    })
    socket.addEventListener("error", (event)=>{
        status.innerText = "已失败"
    })
    socket.addEventListener("close", (event)=>{
        status.innerText = "已关闭"
        console.log("WebSocket closed:", event)
    })
    socket.addEventListener("message", (event)=>{
        message.innerText += event.data
    })
    submit.addEventListener("click", ()=>{
        socket.send(inp.value)
    })
</script>
</body>
</html>
相关推荐
tryCbest37 分钟前
FastAPI中passlib包的作用
python·fastapi·passlib
請你喝杯Java4 小时前
网站部署平台怎么选:Vercel、Cloudflare、ChatGPT Sites 的区别、费用与国内访问
chatgpt·cloudflare·vercel
dunge20264 小时前
2026年9月8日|ChatGPT Pro + Codex:用 GPT‑6 Astra 重做自动化测试
gpt·chatgpt
精彩AI说5 小时前
ChatGPT整理SOP总是步骤不完整?流程拆解、输入输出与异常情况整理方法
chatgpt·流程管理·ai工具·办公效率·sop
承渊政道6 小时前
【从零开始大模型开发与微调:基于PyTorch与ChatGLM】(实战训练自己的ChatGPT从续写模型到对齐助手:RLHF、奖励模型与PPO精读)
人工智能·pytorch·chatgpt·预训练·rlhf·大模型微调
乃嘿仔17 小时前
AI 热点日报 · 2026-09-04
人工智能·chatgpt
ServBay18 小时前
GPT-6 Astra 发布,当 AI 开始自己操作电脑,AGI 还远吗?
gpt·chatgpt·openai
青 春 记 忆20 小时前
零基础入门python66:FastAPI AI标题、摘要和标签
python·fastapi·后端开发
精彩AI说21 小时前
ChatGPT照着参考文档改内容为什么总跑偏?模板结构、字段对应与格式约束方法
chatgpt·ai工具·办公效率·文档整理·chatgpt教程·模板改写
青 春 记 忆21 小时前
零基础入门python65:FastAPI 安全调用大模型API
python·fastapi·后端开发