[Python 网络编程] TCP编程/群聊服务端 (二)
群聊服务端
需求分析：
1. 群聊服务端需支持启动和停止(清理资源);
2. 可以接收客户端的连接; 接收客户端发来的数据
3. 可以将每条信息分发到所有客户端
1） 先搭架子：
#TCP Server
import threading,logging,time,random,datetime
DATEFMT="%H:%M:%S"
FORMAT = "[%(asctime)s]\t [%(threadName)s,%(thread)d] %(message)s"
logging.basicConfig(level=logging.INFO,format=FORMAT,datefmt=DATEFMT)
class ChatServer:
def __init__(self):
pass
def start(self):
pass
def stop(self):
pass
def _accept(self):
pass
def _recv(self):
#接收数据,TODO 分发
pass
2）基础功能：
#TCP Server
import threading,logging,time,random,datetime,socket
DATEFMT="%H:%M:%S"
FORMAT = "[%(asctime)s]\t [%(threadName)s,%(thread)d] %(message)s"
logging.basicConfig(level=logging.INFO,format=FORMAT,datefmt=DATEFMT)
class ChatServer:
def __init__(self,ip='127.0.0.1',port=9999): # 初始化socket
self.addr = (ip,port)
self.sock = socket.socket()
def start(self): # 绑定ip地址/端口,启动监听
self.sock.bind(self.addr)
self.sock.listen()
# accept默认阻塞
threading.Thread(target=self._accept,name='accept').start()
def stop(self):
pass
def _accept(self):# 接收传入的连接
conn,client = self.sock.accept()
# recv默认阻塞
threading.Thread(target=self._recv, args=(conn,),name='recv').start()
def _recv(self,conn): #接收数据,TODO 分发
data = conn.recv(1024)
cs = ChatServer()
cs.start()
3）功能完善
3.1 循环接收所有连接，将接收数据原文分发给所有客户端
#TCP Server
import threading,logging,time,random,datetime,socket
DATEFMT="%H:%M:%S"
FORMAT = "[%(asctime)s]\t [%(threadName)s,%(thread)d] %(message)s"
logging.basicConfig(level=logging.INFO,format=FORMAT,datefmt=DATEFMT)
class ChatServer:
def __init__(self,ip='127.0.0.1',port=9999): # 初始化socket
self.addr = (ip,port)
self.sock = socket.socket()
self.clients = {} #
def start(self): # 绑定ip地址/端口,启动监听
self.sock.bind(self.addr)
self.sock.listen()
# accept默认阻塞
threading.Thread(target=self._accept,name='accept').start()
def stop(self):
pass
def _accept(self):# 接收传入的连接
conn,client = self.sock.accept()
self.clients[client] = conn # (ip,port)二元组
# conn = <socket.socket fd=264, family=AddressFamily.AF_INET, type=SocketKind.SOCK_STREAM, proto=0, laddr=('127.0.0.1', 9999),raddr=('127.0.0.1', 11688)>
# client = ('127.0.0.1', 11688)
logging.info("{}-{}".format(conn,client))
# recv 默认阻塞
threading.Thread(target=self._recv, args=(conn,),name='recv').start()
def _recv(self,conn): # 循环接收数据,TODO 分发
while True:
data = conn.recv(1024)
logging.info(data.decode())
msg = "ACK {}".format(data.decode())
for c in self.clients.values():
c.send(msg.encode())
cs = ChatServer()
cs.start()
e = threading.Event()
def showthreads():
while not e.wait(5):
logging.info(threading.enumerate())
showthreads()
#运行结果：
[15:55:39] [MainThread,7304] [<_MainThread(MainThread, started 7304)>, <Thread(accept, started 7776)>]
#检查服务端状态 C:\Users\zhangsan>netstat -an | find "9999" TCP 127.0.0.1:9999 0.0.0.0:0 LISTENING
客户端连接：
发送消息："hello"
#服务端运行状态变化
[15:55:54] [MainThread,7304] [<_MainThread(MainThread, started 7304)>, <Thread(accept, started 7776)>]
[15:55:58] [accept,7776] <socket.socket fd=404, family=AddressFamily.AF_INET, type=SocketKind.SOCK_STREAM, proto=0, laddr=('127.0.0.1', 9999), raddr=('127.0.0.1', 11863)>-('127.0.0.1', 11863)
[15:55:59] [MainThread,7304] [<_MainThread(MainThread, started 7304)>, <Thread(recv, started 6788)>] #accept线程不见了，先不关心
[15:56:04] [MainThread,7304] [<_MainThread(MainThread, started 7304)>, <Thread(recv, started 6788)>]
[15:56:07] [recv,6788] hello
客户端断开连接：
客户端主动断开连接，服务器抛出了ConnectionAbortedError异常：
#异常
[15:58:57] [recv,6788]
Exception in thread recv:
Traceback (most recent call last):
File "C:\Users\zhangpeng\AppData\Local\Programs\Python\Python35\lib\threading.py", line 914, in _bootstrap_inner
self.run()
File "C:\Users\zhangpeng\AppData\Local\Programs\Python\Python35\lib\threading.py", line 862, in run
self._target(*self._args, **self._kwargs)
File "C:/python/test.py", line 35, in _recv
data = conn.recv(1024)
ConnectionAbortedError: [WinError 10053] 你的主机中的软件中止了一个已建立的连接。
3.2 修复accept线程不能循环接收连接问题
客户端连接：
服务器代码：
#TCP Server
import threading,logging,time,random,datetime,socket
DATEFMT="%H:%M:%S"
FORMAT = "[%(asctime)s]\t [%(threadName)s,%(thread)d] %(message)s"
logging.basicConfig(level=logging.INFO,format=FORMAT,datefmt=DATEFMT)
class ChatServer:
def __init__(self,ip='127.0.0.1',port=9999): # 初始化socket
self.addr = (ip,port)
self.sock = socket.socket()
self.clients = {} #
def start(self): # 绑定ip地址/端口,启动监听
self.sock.bind(self.addr)
self.sock.listen()
# accept默认阻塞
threading.Thread(target=self._accept,name='accept').start()
def stop(self):
pass
def _accept(self):# 接收传入的连接
while True: #修复accept循环接收数据
conn,client = self.sock.accept()
self.clients[client] = conn # (ip,port)二元组
# conn = <socket.socket fd=264, family=AddressFamily.AF_INET, type=SocketKind.SOCK_STREAM, proto=0, laddr=('127.0.0.1', 9999),raddr=('127.0.0.1', 11688)>
# client = ('127.0.0.1', 11688)
logging.info("{}-{}".format(conn,client))
# recv 默认阻塞
threading.Thread(target=self._recv, args=(conn,),name='recv').start()
def _recv(self,conn): # 循环接收数据,TODO 分发
while True:
data = conn.recv(1024)
logging.info(data.decode())
msg = "ACK {}".format(data.decode())
for c in self.clients.values():
c.send(msg.encode())
cs = ChatServer()
cs.start()
e = threading.Event()
def showthreads():
while not e.wait(5):
logging.info(threading.enumerate())
showthreads()
#运行结果
[16:03:56] [MainThread,944] [<_MainThread(MainThread, started 944)>, <Thread(accept, started 660)>]
[16:04:01] [MainThread,944] [<_MainThread(MainThread, started 944)>, <Thread(accept, started 660)>]
[16:04:04] [accept,660] <socket.socket fd=408, family=AddressFamily.AF_INET, type=SocketKind.SOCK_STREAM, proto=0, laddr=('127.0.0.1', 9999), raddr=('127.0.0.1', 11988)>-('127.0.0.1', 11988)
[16:04:06] [MainThread,944] [<_MainThread(MainThread, started 944)>, <Thread(recv, started 8320)>, <Thread(accept, started 660)>] #成功启动recv线程，接收数据
[16:04:11] [MainThread,944] [<_MainThread(MainThread, started 944)>, <Thread(recv, started 8320)>, <Thread(accept, started 660)>]
[16:04:12] [recv,8320] client1
[16:04:15] [accept,660] <socket.socket fd=248, family=AddressFamily.AF_INET, type=SocketKind.SOCK_STREAM, proto=0, laddr=('127.0.0.1', 9999), raddr=('127.0.0.1', 11991)>-('127.0.0.1', 11991)
[16:04:16] [MainThread,944] [<_MainThread(MainThread, started 944)>, <Thread(recv, started 8320)>, <Thread(accept, started 660)>, <Thread(recv, started 7200)>] #又新增一个客户端和recv线程。
[16:04:19] [recv,7200] client2
[16:04:21] [MainThread,944] [<_MainThread(MainThread, started 944)>, <Thread(recv, started 8320)>, <Thread(accept, started 660)>, <Thread(recv, started 7200)>]
[16:04:26] [MainThread,944] [<_MainThread(MainThread, started 944)>, <Thread(recv, started 8320)>, <Thread(accept, started 660)>, <Thread(recv, started 7200)>]
3.3 完善清理资源：
#TCP Server
import threading,logging,time,random,datetime,socket
DATEFMT="%H:%M:%S"
FORMAT = "[%(asctime)s]\t [%(threadName)s,%(thread)d] %(message)s"
logging.basicConfig(level=logging.INFO,format=FORMAT,datefmt=DATEFMT)
class ChatServer:
def __init__(self,ip='127.0.0.1',port=9999):
self.addr = (ip,port)
self.sock = socket.socket()
self.event = threading.Event()
self.clients = {} #
def start(self):
self.sock.bind(self.addr)
self.sock.listen()
threading.Thread(target=self._accept,name='accept').start()
def stop(self): # 完善清理工作
for c in self.clients.values():
c.close()
self.sock.close()
self.event.wait(1)
self.event.set()
def _accept(self):
while not self.event.is_set():
conn,client = self.sock.accept()
self.clients[client] = conn
logging.info("{}-{}".format(conn,client))
threading.Thread(target=self._recv, args=(conn,),name='recv').start()
def _recv(self,conn):
while not self.event.is_set():
data = conn.recv(1024)
logging.info(data.decode())
msg = "ACK {}".format(data.decode())
for c in self.clients.values():
c.send(msg.encode())
cs = ChatServer()
cs.start()
e = threading.Event()
def showthreads():
while not e.wait(5):
logging.info(threading.enumerate())
showthreads()
e.wait(30)
cs.stop()
3.4 添加Server端主动断开和Client端通知断开机制，修复处理客户端主动断开引发的异常
客户端发送"quit"测试主动断开功能：
服务端代码：
#TCP Server
import threading,logging,time,random,datetime,socket
DATEFMT="%H:%M:%S"
FORMAT = "[%(asctime)s]\t [%(threadName)s,%(thread)d] %(message)s"
logging.basicConfig(level=logging.INFO,format=FORMAT,datefmt=DATEFMT)
class ChatServer:
def __init__(self,ip='127.0.0.1',port=9999):
self.addr = (ip,port)
self.sock = socket.socket()
self.event = threading.Event()
self.clients = {} #
def start(self):
self.sock.bind(self.addr)
self.sock.listen()
threading.Thread(target=self._accept,name='accept').start()
def stop(self):
for c in self.clients.values():
c.close()
self.sock.close()
self.event.wait(3)
self.event.set()
def _accept(self):
while not self.event.is_set():
conn,client = self.sock.accept()
self.clients[client] = conn
logging.info("{}-{}".format(conn,client))
# recv 默认阻塞
threading.Thread(target=self._recv, args=(conn,client),name='recv').start()
def _recv(self,conn,client):
while not self.event.is_set():
try:
data = conn.recv(1024)
except Exception as e:
logging.info(e)
data = 'quit'.encode()
logging.info(data.decode())
# Client通知退出机制
if data.decode() == 'quit' or data.decode == '':
# logging.info(data.decode())
conn.send('Disconnect!!!'.encode())
self.clients.pop(client)
conn.close()
break
msg = "ACK {}".format(data.decode())
for c in self.clients.values():
c.send(msg.encode())
cs = ChatServer()
cs.start()
e = threading.Event()
def showthreads():
while not e.wait(5):
logging.info(threading.enumerate())
threading.Thread(target=showthreads,daemon=True,name='showthreads').start()
while True: # Sever控制台退出方式
cmd = input('>>> ').strip()
if cmd == 'quit':
cs.stop()
break
#运行结果：
>>> [17:32:33] [showthreads,8732] [<_MainThread(MainThread, started 3464)>, <Thread(showthreads, started daemon 8732)>, <Thread(accept, started 4388)>]
[17:32:38] [showthreads,8732] [<_MainThread(MainThread, started 3464)>, <Thread(showthreads, started daemon 8732)>, <Thread(accept, started 4388)>]
[17:32:43] [accept,4388] <socket.socket fd=360, family=AddressFamily.AF_INET, type=SocketKind.SOCK_STREAM, proto=0, laddr=('127.0.0.1', 9999), raddr=('127.0.0.1', 13415)>-('127.0.0.1', 13415)
[17:32:43] [showthreads,8732] [<_MainThread(MainThread, started 3464)>, <Thread(showthreads, started daemon 8732)>, <Thread(recv, started 5556)>, <Thread(accept, started 4388)>]
[17:32:47] [accept,4388] <socket.socket fd=384, family=AddressFamily.AF_INET, type=SocketKind.SOCK_STREAM, proto=0, laddr=('127.0.0.1', 9999), raddr=('127.0.0.1', 13417)>-('127.0.0.1', 13417)
[17:32:48] [showthreads,8732] [<_MainThread(MainThread, started 3464)>, <Thread(showthreads, started daemon 8732)>, <Thread(recv, started 5556)>, <Thread(accept, started 4388)>, <Thread(recv, started 8248)>]
[17:32:51] [recv,5556] test1
[17:32:53] [showthreads,8732] [<_MainThread(MainThread, started 3464)>, <Thread(showthreads, started daemon 8732)>, <Thread(recv, started 5556)>, <Thread(accept, started 4388)>, <Thread(recv, started 8248)>]
[17:32:55] [recv,8248] test2
[17:32:58] [showthreads,8732] [<_MainThread(MainThread, started 3464)>, <Thread(showthreads, started daemon 8732)>, <Thread(recv, started 5556)>, <Thread(accept, started 4388)>, <Thread(recv, started 8248)>]
[17:33:00] [recv,8248] quit
[17:33:03] [showthreads,8732] [<_MainThread(MainThread, started 3464)>, <Thread(showthreads, started daemon 8732)>, <Thread(recv, started 5556)>, <Thread(accept, started 4388)>]
[17:33:07] [recv,5556] quit
[17:33:08] [showthreads,8732] [<_MainThread(MainThread, started 3464)>, <Thread(showthreads, started daemon 8732)>, <Thread(accept, started 4388)>]
其它方法：
socket.recv(bufsize[,flags]) 获取数据。默认是阻塞的方式
socket.recvfrom(bufsize[,flags]) 获取数据，返回一个二元组(bytes,address)(可用于udp)
socket.recv_into(buffer[,nbytes[,flags]]) 获取到nbytes的数据后，存储到buffer中。如果nbytes没有指定或0，将buffer大小的数据存入buffer中。返回接收的字节数。
socket.recvfrom_into(buffer[,nbytes[,flags]]) 获取数据，返回一个二元组(bytes,address)到buffer中
socket.send(bytes[,flags]) TCP发送数据
socket.sendall(bytes[,flags]) TCP发送全部数据，成功返回None
socket.sendto(string[,flag],address) UDP发送数据
socket.sendfile(file,offset=0,count=None) 发送一个文件直到EOF，使用高性能的os.sendfile机制，返回发送的字节数。如果win下不支持sendfile，或者不是普通文件，使用send()发送文件。offset告诉起始位置。3.5版本开始
socket.makefile(mode='r', buffering=None, *, encoding=None, errors=None, newline=None)
创建一个与该套接字相关联的文件对象。
socket.getpeername() 返回连接套接字的远程地址。返回值通常是元祖(ipaddr,port)
socket.getsockname() 返回套接字自己的地址。通常是一个元祖(ipaddr,port)
socket.setblocking(flag) 如果flag为0，则将套接字设为非阻塞模式，否则将套接字设为阻塞模式(默认值)。非阻塞模式下，如果调用recv()没有发现任何数据，或send()调用无法立即发送数据，那么将引起socket.error异常。
socket.settimeout(value) 设置套接字操作的超时期，timeout是一个浮点数，单位是秒。值为None表示没有超时期。一般，超时期应该在刚创建套接字时设置，因为它们可能用于连接的操作(如connect())
socket.setsockopt(level,optname,value) 设置套接字选项的值。比如缓冲区大小。所有SO_* 开头的常量，不同系统、不同版本都不尽相同
4） 总结
从需求分析，到建立框架，完善基本功能，测试/修改，最终虽然完成了一个看似基本功能已经实现的群聊服务端，
但以上的所有例子只是测试，练习底层的socket使用，生产环境中一般都是使用封装过的socket，且程序还有很多异常没有处理。
conn.close() 服务端主动和客户端断开
sock.close() 服务端主动关闭服务端socket
recv，send，close，都可能在操作过程中出现异常，客户端主动断开服务端也会抛ConnectionAbortedError异常，如果服务端不处理这个异常，客户端下次连接，服务端就不能正常recv数据。
