1 短连接

HTTP/1.0 及以前的版本采用的都是短连接

2 长连接

HTTP/1.1 采用的都是长连接

不用gevent, 实现单进程，单线程，长连接，且能并发处理多个浏览器请求的http服务器
核心原理：new_socket.setblocking(False)把套接字设为非阻塞

from socket import *
import re
def serve_client(client_socket, request):
    request_lines = request.splitlines()
    print(request_lines)
    file_name = ""
    ret = re.match(r"[^/]+(/[^ ]*)", request_lines[0])
    if ret:
        file_name = ret.group(1)
        if file_name == "/":
            file_name = "/index.html"
    try:
        f = open("./html"+file_name, "rb")
    except:
        response = "HTTP/1.1 404 NOT FOUND\n\n"
        response += "-----file not fonund-----"
        client_socket.send(response.encode("utf-8"))
    else:
        response_body = f.read()
        f.close()
        response_header = "HTTP/1.1 200 OK\n"
        response_header += "Content-Length:{}\n".format(len(response_body))
        response_header += "\n"
        response = response_header.encode("utf-8") + response_body
        client_socket.send(response)
if __name__ == "__main__":
    tcp_socket = socket(AF_INET, SOCK_STREAM)
    tcp_socket.setsockopt(SOL_SOCKET, SO_REUSEADDR, 1)
    tcp_socket.bind(("", 7890))
    tcp_socket.listen(128)
    tcp_socket.setblocking(False)
    client_socket_list = list()
    while True:
        try:
            new_socket, client_addr = tcp_socket.accept()
        except Exception as e:
            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 e:
                pass
            else:
                if recv_data:
                    serve_client(client_socket, recv_data)
                else:
                    client_socket.close()
                    client_socket_list.remove(client_socket)
    tcp_socket.close()