3.socket编程示例

#block_server.py 非阻塞IO示例
#有个疑惑:下面的connfd的blockind要设置为True,不然会出错,待解决
from socket import *
from time import ctime,sleep

s = socket()
s.bind(("0.0.0.0",18888))
s.listen(10)
#设置s为非阻塞状态
s.setblocking(False)

while True:
    print("等待连接...")
    try:
        connfd,addr = s.accept()
    except BlockingIOError:
        sleep(2)
        print(ctime())
        continue
    print("connect from",addr)
    while True:
        connfd.setblocking(True)
        data = connfd.recv(1024)
        if not data:
            break
        print(data.decode())
        serv_msg = input("服务端消息>")
        connfd.send(serv_msg.encode())
    connfd.close()
s.close()
=========================================
#timeout_server.py 超时检测示例及traceback
from socket import *
from time import sleep,ctime
import traceback

HOST = "0.0.0.0"
PORT = 14444
s = socket()
s.bind((HOST,PORT))
s.listen(5)
#设置超时检测
s.settimeout(5)
while True:
    print("服务端等待连接.....")
    try:
        c,addr = s.accept()
    except Exception:
        traceback.print_exc()
        continue
    print("connect from",addr)
    while True:
        data = c.recv(1024)
        if not data:
            break
        print(data.decode())
        serv_msg = input("服务端消息>")
        c.send(serv_msg.encode())
    c.close()
s.close()
==========================================
#select_server.py select服务端示例
from socket import *
from select import *

HOST = "0.0.0.0"
PORT = 18888
s = socket()
s.setsockopt(SOL_SOCKET,SO_REUSEADDR,1)
s.bind((HOST,PORT))
s.listen(5)

#将需要监控的IO放入rlist
rlist = [s]
wlist = []
xlist = []
print("select服务器启动成功")
while True:
    print(f"select正在监控阻塞套接字{rlist}")
    print(f"目前列表中有{len(rlist)}个套接字")
    rl,wl,xl = select(rlist,wlist,xlist)
    for r in rl:
        #套接字准备就绪
        if r is s:
            conn,addr = r.accept()
            print("Connect from",addr)
            #把新的套接字加入监控列表
            rlist.append(conn)
        else:
            data = r.recv(1024)
            if not data:
                rlist.remove(r)
                r.close()
                break
            print("received:",data.decode())
            r.send("已经收到".encode())
    for w in wl:
        pass
    for x in xl:
        pass
===============================================
#select_server2_wlist.py select服务端示例,演示wlist,xlist用法
from socket import *
from select import *
import sys

HOST = "0.0.0.0"
PORT = 18888
s = socket()
s.setsockopt(SOL_SOCKET,SO_REUSEADDR,1)
s.bind((HOST,PORT))
s.listen(5)

#将需要监控的IO放入rlist
rlist = [s]
wlist = []
xlist = [s]
print("select服务器启动成功")
while True:
    print(f"select正在监控阻塞套接字{rlist}")
    print(f"目前列表中有{len(rlist)}个套接字")
    rl,wl,xl = select(rlist,wlist,xlist)
    for r in rl:
        #套接字准备就绪
        if r is s:
            conn,addr = r.accept()
            print("Connect from",addr)
            #把新的套接字加入监控列表
            rlist.append(conn)
        else:
            data = r.recv(1024)
            if not data:
                rlist.remove(r)
                r.close()
                break
            else:
                print(f"received from {str(r.getpeername())}:{data.decode()}",)
                #接收完消息,把套接字加入wlist列表,待处理(当wlist内有内容,select会立即返回)
                wlist.append(r)
    # 当上一步待处理套接字加入wlist,这步立刻处理,处理完把该套接字移出wlist
    for w in wl:
        w.send(f"已经收到你的消息{str(w.getpeername())}".encode())
        wlist.remove(w)
    for x in xl:
        #如果套接字出错,结束整个程序
        if x is s:
            s.close()
            sys.exit()
    =============================================================
    #unix_send.py 本地套接字简单应用,发送端
    from socket import *
    import sys,os
    #确定用哪个文件进行通信
    server_address = "./test"
    #判断文件是否存在,如已存在则删除
    if os.path.exists(server_address):
        os.unlink(server_address)
    #创建本地套接字
    s = socket(AF_UNIX,SOCK_STREAM)
    #绑定本地套接字文件
    s.bind(server_address)
    #监听
    s.listen(5)
    #收发消息
    while True:
        c,addr = s.accept()
        while True:
            data = c.recv(1024)
            if data:
                print(data.decode())
                c.sendall("收到消息".encode())
            else:
                break
        c.close()
    s.close()
    ========================================================
    #unix_recv.py 本地套接字简单应用,接收端
    from socket import *
    server_address = "./test"
    s = socket(AF_UNIX,SOCK_STREAM)
    s.connect(server_address)
    while True:
        message = input("客户端消息")
        if message:
            s.sendall(message.encode())
            recv_msg = s.recv(1024)
            print(recv_msg.decode())
        else:
            break
    s.close()