Python之FTP实现
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1 import socket 2 import struct 3 import json 4 import subprocess 5 import os 6 7 class MYTCPServer: 8 address_family = socket.AF_INET 9 10 socket_type = socket.SOCK_STREAM 11 12 allow_reuse_address = False 13 14 max_packet_size = 8192 15 16 coding='utf-8' 17 18 request_queue_size = 5 19 20 server_dir='file_upload' 21 22 def __init__(self, server_address, bind_and_activate=True): 23 """Constructor. May be extended, do not override.""" 24 self.server_address=server_address 25 self.socket = socket.socket(self.address_family, 26 self.socket_type) 27 if bind_and_activate: 28 try: 29 self.server_bind() 30 self.server_activate() 31 except: 32 self.server_close() 33 raise 34 35 def server_bind(self): 36 """Called by constructor to bind the socket. 37 """ 38 if self.allow_reuse_address: 39 self.socket.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1) 40 self.socket.bind(self.server_address) 41 self.server_address = self.socket.getsockname() 42 43 def server_activate(self): 44 """Called by constructor to activate the server. 45 """ 46 self.socket.listen(self.request_queue_size) 47 48 def server_close(self): 49 """Called to clean-up the server. 50 """ 51 self.socket.close() 52 53 def get_request(self): 54 """Get the request and client address from the socket. 55 """ 56 return self.socket.accept() 57 58 def close_request(self, request): 59 """Called to clean up an individual request.""" 60 request.close() 61 62 def run(self): 63 while True: 64 self.conn,self.client_addr=self.get_request() 65 print('from client ',self.client_addr) 66 while True: 67 try: 68 head_struct = self.conn.recv(4) 69 if not head_struct:break 70 71 head_len = struct.unpack('i', head_struct)[0] 72 head_json = self.conn.recv(head_len).decode(self.coding) 73 head_dic = json.loads(head_json) 74 75 print(head_dic) 76 #head_dic={'cmd':'put','filename':'a.txt','filesize':123123} 77 cmd=head_dic['cmd'] 78 if hasattr(self,cmd): 79 func=getattr(self,cmd) 80 func(head_dic) 81 except Exception: 82 break 83 84 def put(self,args): 85 file_path=os.path.normpath(os.path.join( 86 self.server_dir, 87 args['filename'] 88 )) 89 90 filesize=args['filesize'] 91 recv_size=0 92 print('----->',file_path) 93 with open(file_path,'wb') as f: 94 while recv_size < filesize: 95 recv_data=self.conn.recv(self.max_packet_size) 96 f.write(recv_data) 97 recv_size+=len(recv_data) 98 print('recvsize:%s filesize:%s' %(recv_size,filesize)) 99 100 101 tcpserver1=MYTCPServer(('127.0.0.1',8080)) 102 103 tcpserver1.run() 104 105 106 107 108 109 110 #下列代码与本题无关 111 class MYUDPServer: 112 113 """UDP server class.""" 114 address_family = socket.AF_INET 115 116 socket_type = socket.SOCK_DGRAM 117 118 allow_reuse_address = False 119 120 max_packet_size = 8192 121 122 coding='utf-8' 123 124 def get_request(self): 125 data, client_addr = self.socket.recvfrom(self.max_packet_size) 126 return (data, self.socket), client_addr 127 128 def server_activate(self): 129 # No need to call listen() for UDP. 130 pass 131 132 def shutdown_request(self, request): 133 # No need to shutdown anything. 134 self.close_request(request) 135 136 def close_request(self, request): 137 # No need to close anything. 138 pass
1 import socket 2 import struct 3 import json 4 import os 5 6 7 class MYTCPClient: 8 address_family = socket.AF_INET 9 10 socket_type = socket.SOCK_STREAM 11 12 allow_reuse_address = False 13 14 max_packet_size = 8192 15 16 coding='utf-8' 17 18 request_queue_size = 5 19 20 def __init__(self, server_address, connect=True): 21 self.server_address=server_address 22 self.socket = socket.socket(self.address_family, 23 self.socket_type) 24 if connect: 25 try: 26 self.client_connect() 27 except: 28 self.client_close() 29 raise 30 31 def client_connect(self): 32 self.socket.connect(self.server_address) 33 34 def client_close(self): 35 self.socket.close() 36 37 def run(self): 38 while True: 39 inp=input(">>: ").strip() 40 if not inp:continue 41 l=inp.split() 42 cmd=l[0] 43 if hasattr(self,cmd): 44 func=getattr(self,cmd) 45 func(l) 46 47 48 def put(self,args): 49 cmd=args[0] 50 filename=args[1] 51 if not os.path.isfile(filename): 52 print('file:%s is not exists' %filename) 53 return 54 else: 55 filesize=os.path.getsize(filename) 56 57 head_dic={'cmd':cmd,'filename':os.path.basename(filename),'filesize':filesize} 58 print(head_dic) 59 head_json=json.dumps(head_dic) 60 head_json_bytes=bytes(head_json,encoding=self.coding) 61 62 head_struct=struct.pack('i',len(head_json_bytes)) 63 self.socket.send(head_struct) 64 self.socket.send(head_json_bytes) 65 send_size=0 66 with open(filename,'rb') as f: 67 for line in f: 68 self.socket.send(line) 69 send_size+=len(line) 70 print(send_size) 71 else: 72 print('upload successful') 73 74 75 76 client=MYTCPClient(('127.0.0.1',8080)) 77 78 client.run()
认证客户端的链接合法性
如果你想在分布式系统中实现一个简单的客户端链接认证功能，又不像SSL那么复杂，那么利用hmac+加盐的方式来实现
1 #_*_coding:utf-8_*_ 2 __author__ = 'Linhaifeng' 3 from socket import * 4 import hmac,os 5 6 secret_key=b'linhaifeng bang bang bang' 7 def conn_auth(conn): 8 ''' 9 认证客户端链接 10 :param conn: 11 :return: 12 ''' 13 print('开始验证新链接的合法性') 14 msg=os.urandom(32) 15 conn.sendall(msg) 16 h=hmac.new(secret_key,msg) 17 digest=h.digest() 18 respone=conn.recv(len(digest)) 19 return hmac.compare_digest(respone,digest) 20 21 def data_handler(conn,bufsize=1024): 22 if not conn_auth(conn): 23 print('该链接不合法,关闭') 24 conn.close() 25 return 26 print('链接合法,开始通信') 27 while True: 28 data=conn.recv(bufsize) 29 if not data:break 30 conn.sendall(data.upper()) 31 32 def server_handler(ip_port,bufsize,backlog=5): 33 ''' 34 只处理链接 35 :param ip_port: 36 :return: 37 ''' 38 tcp_socket_server=socket(AF_INET,SOCK_STREAM) 39 tcp_socket_server.bind(ip_port) 40 tcp_socket_server.listen(backlog) 41 while True: 42 conn,addr=tcp_socket_server.accept() 43 print('新连接[%s:%s]' %(addr[0],addr[1])) 44 data_handler(conn,bufsize) 45 46 if __name__ == '__main__': 47 ip_port=('127.0.0.1',9999) 48 bufsize=1024 49 server_handler(ip_port,bufsize)
1 #_*_coding:utf-8_*_ 2 __author__ = 'Linhaifeng' 3 from socket import * 4 import hmac,os 5 6 secret_key=b'linhaifeng bang bang bang' 7 def conn_auth(conn): 8 ''' 9 验证客户端到服务器的链接 10 :param conn: 11 :return: 12 ''' 13 msg=conn.recv(32) 14 h=hmac.new(secret_key,msg) 15 digest=h.digest() 16 conn.sendall(digest) 17 18 def client_handler(ip_port,bufsize=1024): 19 tcp_socket_client=socket(AF_INET,SOCK_STREAM) 20 tcp_socket_client.connect(ip_port) 21 22 conn_auth(tcp_socket_client) 23 24 while True: 25 data=input('>>: ').strip() 26 if not data:continue 27 if data == 'quit':break 28 29 tcp_socket_client.sendall(data.encode('utf-8')) 30 respone=tcp_socket_client.recv(bufsize) 31 print(respone.decode('utf-8')) 32 tcp_socket_client.close() 33 34 if __name__ == '__main__': 35 ip_port=('127.0.0.1',9999) 36 bufsize=1024 37 client_handler(ip_port,bufsize)
1 #_*_coding:utf-8_*_ 2 __author__ = 'Linhaifeng' 3 from socket import * 4 5 def client_handler(ip_port,bufsize=1024): 6 tcp_socket_client=socket(AF_INET,SOCK_STREAM) 7 tcp_socket_client.connect(ip_port) 8 9 while True: 10 data=input('>>: ').strip() 11 if not data:continue 12 if data == 'quit':break 13 14 tcp_socket_client.sendall(data.encode('utf-8')) 15 respone=tcp_socket_client.recv(bufsize) 16 print(respone.decode('utf-8')) 17 tcp_socket_client.close() 18 19 if __name__ == '__main__': 20 ip_port=('127.0.0.1',9999) 21 bufsize=1024 22 client_handler(ip_port,bufsize)
1 #_*_coding:utf-8_*_ 2 __author__ = 'Linhaifeng' 3 from socket import * 4 import hmac,os 5 6 secret_key=b'linhaifeng bang bang bang1111' 7 def conn_auth(conn): 8 ''' 9 验证客户端到服务器的链接 10 :param conn: 11 :return: 12 ''' 13 msg=conn.recv(32) 14 h=hmac.new(secret_key,msg) 15 digest=h.digest() 16 conn.sendall(digest) 17 18 def client_handler(ip_port,bufsize=1024): 19 tcp_socket_client=socket(AF_INET,SOCK_STREAM) 20 tcp_socket_client.connect(ip_port) 21 22 conn_auth(tcp_socket_client) 23 24 while True: 25 data=input('>>: ').strip() 26 if not data:continue 27 if data == 'quit':break 28 29 tcp_socket_client.sendall(data.encode('utf-8')) 30 respone=tcp_socket_client.recv(bufsize) 31 print(respone.decode('utf-8')) 32 tcp_socket_client.close() 33 34 if __name__ == '__main__': 35 ip_port=('127.0.0.1',9999) 36 bufsize=1024 37 client_handler(ip_port,bufsize)
socketserver实现并发
基于tcp的套接字，关键就是两个循环，一个链接循环，一个通信循环
socketserver模块中分两大类：server类（解决链接问题）和request类（解决通信问题）
server类：
request类：
继承关系:
以下述代码为例，分析socketserver源码：
ftpserver=socketserver.ThreadingTCPServer(('127.0.0.1',8080),FtpServer)
ftpserver.serve_forever()
查找属性的顺序：ThreadingTCPServer->ThreadingMixIn->TCPServer->BaseServer
- 实例化得到ftpserver，先找类ThreadingTCPServer的__init__,在TCPServer中找到，进而执行server_bind,server_active
- 找ftpserver下的serve_forever,在BaseServer中找到，进而执行self._handle_request_noblock()，该方法同样是在BaseServer中
- 执行self._handle_request_noblock()进而执行request, client_address = self.get_request()（就是TCPServer中的self.socket.accept()），然后执行self.process_request(request, client_address)
- 在ThreadingMixIn中找到process_request，开启多线程应对并发，进而执行process_request_thread，执行self.finish_request(request, client_address)
- 上述四部分完成了链接循环，本部分开始进入处理通讯部分，在BaseServer中找到finish_request,触发我们自己定义的类的实例化，去找__init__方法，而我们自己定义的类没有该方法，则去它的父类也就是BaseRequestHandler中找....
源码分析总结：
基于tcp的socketserver我们自己定义的类中的
- self.server即套接字对象
- self.request即一个链接
- self.client_address即客户端地址
基于udp的socketserver我们自己定义的类中的
- self.request是一个元组（第一个元素是客户端发来的数据，第二部分是服务端的udp套接字对象），如(b'adsf', <socket.socket fd=200, family=AddressFamily.AF_INET, type=SocketKind.SOCK_DGRAM, proto=0, laddr=('127.0.0.1', 8080)>)
- self.client_address即客户端地址
1 import socketserver 2 import struct 3 import json 4 import os 5 class FtpServer(socketserver.BaseRequestHandler): 6 coding='utf-8' 7 server_dir='file_upload' 8 max_packet_size=1024 9 BASE_DIR=os.path.dirname(os.path.abspath(__file__)) 10 def handle(self): 11 print(self.request) 12 while True: 13 data=self.request.recv(4) 14 data_len=struct.unpack('i',data)[0] 15 head_json=self.request.recv(data_len).decode(self.coding) 16 head_dic=json.loads(head_json) 17 # print(head_dic) 18 cmd=head_dic['cmd'] 19 if hasattr(self,cmd): 20 func=getattr(self,cmd) 21 func(head_dic) 22 def put(self,args): 23 file_path = os.path.normpath(os.path.join( 24 self.BASE_DIR, 25 self.server_dir, 26 args['filename'] 27 )) 28 29 filesize = args['filesize'] 30 recv_size = 0 31 print('----->', file_path) 32 with open(file_path, 'wb') as f: 33 while recv_size < filesize: 34 recv_data = self.request.recv(self.max_packet_size) 35 f.write(recv_data) 36 recv_size += len(recv_data) 37 print('recvsize:%s filesize:%s' % (recv_size, filesize)) 38 39 40 ftpserver=socketserver.ThreadingTCPServer(('127.0.0.1',8080),FtpServer) 41 ftpserver.serve_forever()
1 import socket 2 import struct 3 import json 4 import os 5 6 7 8 class MYTCPClient: 9 address_family = socket.AF_INET 10 11 socket_type = socket.SOCK_STREAM 12 13 allow_reuse_address = False 14 15 max_packet_size = 8192 16 17 coding='utf-8' 18 19 request_queue_size = 5 20 21 def __init__(self, server_address, connect=True): 22 self.server_address=server_address 23 self.socket = socket.socket(self.address_family, 24 self.socket_type) 25 if connect: 26 try: 27 self.client_connect() 28 except: 29 self.client_close() 30 raise 31 32 def client_connect(self): 33 self.socket.connect(self.server_address) 34 35 def client_close(self): 36 self.socket.close() 37 38 def run(self): 39 while True: 40 inp=input(">>: ").strip() 41 if not inp:continue 42 l=inp.split() 43 cmd=l[0] 44 if hasattr(self,cmd): 45 func=getattr(self,cmd) 46 func(l) 47 48 49 def put(self,args): 50 cmd=args[0] 51 filename=args[1] 52 if not os.path.isfile(filename): 53 print('file:%s is not exists' %filename) 54 return 55 else: 56 filesize=os.path.getsize(filename) 57 58 head_dic={'cmd':cmd,'filename':os.path.basename(filename),'filesize':filesize} 59 print(head_dic) 60 head_json=json.dumps(head_dic) 61 head_json_bytes=bytes(head_json,encoding=self.coding) 62 63 head_struct=struct.pack('i',len(head_json_bytes)) 64 self.socket.send(head_struct) 65 self.socket.send(head_json_bytes) 66 send_size=0 67 with open(filename,'rb') as f: 68 for line in f: 69 self.socket.send(line) 70 send_size+=len(line) 71 print(send_size) 72 else: 73 print('upload successful') 74 75 76 77 78 client=MYTCPClient(('127.0.0.1',8080)) 79 80 client.run()
作业：
