WSGI原理

web_server:

import socket
import time
import multiprocessing
import re
import mini_frame

class WSGIServer(object):
    def __init__(self):
        # 1.创建socket对象
        self.tcp_server_socket = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
        # 2.设置重复使用地址
        self.tcp_server_socket.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1)
        # 3.绑定端口
        self.tcp_server_socket.bind(("", 7890))
        # 4.设置监听状态
        self.tcp_server_socket.listen(128)
    
    def clinet_server(self,new_client_socket):
        # 1.接受消息
        request = new_client_socket.recv(1024).decode("utf-8")
        lines = request.splitlines()
        # 2.匹配请求网页
        request_name = re.match(r"[^/]+(/[^ ]*)",lines[0])
        file_name = request_name.group(1)
        if file_name == "/":
            file_name = "/index.html"

        # 返回数据给浏览器
        if not file_name.endswith(".py"):
            # 3.打开文件
            try:
                f = open("./html" + file_name,"rb")
            except Exception as ret:
                pass
            else:
                html_content = f.read()

                # 4.创建header和body
                response_body = html_content
                response_header = "HTTP/1.1 200 ok
"
                response_header += "Content-Length:%d
" % len(response_body)
                response_header += "
"
                response = response_header.encode("utf-8") + response_body
                # 5.发送
                new_client_socket.send(response)
            finally:
                f.close()
        else:
            # 如果是.py结尾,则认为是动态页面请求/
            env = dict();
            env['PATH_INFO'] = file_name
            # application(字典， 方法名) 固定用法
            body = mini_frame.application(env, self.start_respones_header)
            # 拼装header头
            header = "HTTP/1.1 %s
" % self.status
            for temp in self.headers:
                header += "%s:%s
" % (temp[0], temp[1])
            header += "
"
            # 拼装返回数据
            response = header + body
            # 发送数据
            new_client_socket.send(response.encode("utf-8"))

        # 6.关闭socket
        # new_client_socket.close()

    def start_respones_header(self, status, headers):
        """接受并保存application传过来的值"""
        self.status = status
        self.headers = [("server","mini_web v1.0")]
        self.headers += headers
    
    
    def run_forever(self):
        """运行"""
        while True:
            # 5.接收客户地址，创建新socket
            new_client_socket,client_addr = self.tcp_server_socket.accept()
            # 6.为新客户端服务
            p = multiprocessing.Process(target=self.clinet_server,args=(new_client_socket,))
            p.start()
            # 7.关闭新客户端
            new_client_socket.close()
        # 7.关闭socket
        self.tcp_server_socket.close()

def main():
    wsgi_server = WSGIServer()
    wsgi_server.run_forever()

if __name__ == '__main__':
    main()

mini_frame.py:

def login():
    """模拟登陆页面"""
    return "---login---welcome to python--->time:%s" % time.ctime()

def index():
    """模拟主页"""
    return "----index----"

def application(env, start_respones):
    # 调用传过来的方法，传值
    start_respones('200 ok',[("Content-Type","text/html;charset=utf-8")])
    # 接受字典传过来的数据
    file_name = env['PATH_INFO']
    # 判断客户请求
    if file_name == "/index.py":
        return index()
    elif file_name == "/login.py":
        return login()
    else:
        return "python 中国"