Python解析HTTP请求报文

from email import parser, policy
from email.message import Message
from typing import Any

ENTER = "\n"
CLRF = "\r\n"

def http_parse(http_pkg:str) -> tuple[str, dict[str,str], Any]:
    """
    http报文初步解析函数
    参数：http报文字符串
    返回：http起始行，headers, body
    """
    res:tuple[str, dict[str,str], Any]
    if ENTER in http_pkg:    # 处理非CLRF分割的http报文
        res = http_pkg_split(ENTER, http_pkg)
    elif CLRF in http_pkg:
        res = http_pkg_split(CLRF, http_pkg)

    return res

def http_pkg_split(sep:str, http_pkg:str) -> tuple[str, dict[str,str], Any]:
    """
    http报文分割函数
    参数：http报文字符串，分割字符
    返回：http起始行，headers, body
    """
    tmp:list[str] = http_pkg.split(sep=sep, maxsplit=1)
    
    start_line:str = tmp[0]
    
    others:str = tmp[1]     # 去除http报文起始行之后，剩余的内容应完全遵从MIME数据格式
    # 指定policy为HTTP，使得遵循 RFC 2822以及当前的各种 MIME RFC（RFC 5322, RFC 2047)
    p:parser.Parser = parser.Parser(policy=policy.HTTP)
    msg:Message = p.parsestr(text=others, headersonly=False)   # 解析header和body
    
    headers:dict[str, str] = {}
    for k, v in msg.items():
        headers[k] = str(v)

    body:Any = msg.get_payload()
    
    return start_line, headers, body

if __name__ == "__main__":
    http_pkg:str = """GET / HTTP/1.1
Host: petstore.swagger.io
Content-Length: 171705
Sec-Ch-Ua: "(Not(A:Brand";v="8", "Chromium";v="99"
Accept: application/json
Content-Type: multipart/form-data; boundary=----WebKitFormBoundaryUmjLZJ95KycutKTH
Sec-Ch-Ua-Mobile: ?0
User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/99.0.4844.74 Safari/537.36
Sec-Ch-Ua-Platform: "Linux"
Origin: https://petstore.swagger.io
Sec-Fetch-Site: same-origin
Sec-Fetch-Mode: cors
Sec-Fetch-Dest: empty
Referer: https://petstore.swagger.io/
Accept-Encoding: gzip, deflate
Accept-Language: zh-CN,zh;q=0.9

------WebKitFormBoundaryUmjLZJ95KycutKTH
Content-Disposition: form-data; name="additionalMetadata"

111
------WebKitFormBoundaryUmjLZJ95KycutKTH--
"""
    res = http_parse(http_pkg=http_pkg)
    print(res)