18 11 27 长连接 短链接

---恢复内容开始---

 http  协议有着 1.0  和1.1   在安卓爆发前都是用着 1,0  的协议

短链接  : 如 在一个网页中  先三次握手  拿到了主要数据  马上四次挥手  分析数据后  再进行三次握手  下载改页面所需要的图片

长连接  : 直接进行 三次握手 后拿完所有的资源  之后进行 四次挥手        

 由于  安卓爆发  许多网站都有了大量的 图片  所以基本都用了长连接

下面是一个单线程  不堵塞  长连接

import socket
import re


def service_client(new_socket, request):
    """为这个客户端返回数据"""

    # 1. 接收浏览器发送过来的请求 ，即http请求  
    # GET / HTTP/1.1
    # .....
    # request = new_socket.recv(1024).decode("utf-8")
    # print(">>>"*50)
    # print(request)

    request_lines = request.splitlines()
    print("")
    print(">"*20)
    print(request_lines)

    # GET /index.html HTTP/1.1
    # get post put del
    file_name = ""
    ret = re.match(r"[^/]+(/[^ ]*)", request_lines[0])
    if ret:
        file_name = ret.group(1)
        # print("*"*50, file_name)
        if file_name == "/":
            file_name = "/index.html"

    # 2. 返回http格式的数据，给浏览器
    
    try:
        f = open("./html" + file_name, "rb")
    except:
        response = "HTTP/1.1 404 NOT FOUND
"
        response += "
"
        response += "------file not found-----"
        new_socket.send(response.encode("utf-8"))
    else:
        html_content = f.read()
        f.close()

        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

        new_socket.send(response)


def main():
    """用来完成整体的控制"""
    # 1. 创建套接字
    tcp_server_socket = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
    tcp_server_socket.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1)

    # 2. 绑定
    tcp_server_socket.bind(("", 7890))

    # 3. 变为监听套接字
    tcp_server_socket.listen(128)
    tcp_server_socket.setblocking(False)  # 将套接字变为非堵塞

    client_socket_list = list()
    while True:
        # 4. 等待新客户端的链接
        try:
            new_socket, client_addr = tcp_server_socket.accept()
        except Exception as ret:
            pass
        else:
            new_socket.setblocking(False)
            client_socket_list.append(new_socket)


        for client_socket in client_socket_list:
            try:
                recv_data = client_socket.recv(1024).decode("utf-8")
            except Exception as ret:
                pass
            else:
                if recv_data:
                    service_client(client_socket, recv_data)
                else:
                    client_socket.close()
                    client_socket_list.remove(client_socket)

    # 关闭监听套接字
    tcp_server_socket.close()


if __name__ == "__main__":
    main()