FTP-成型版本

1. 旧知识回顾-反射

hasattr(object, name)

说明：判断对象object是否包含名为name的属性（方法）

测试代码如下：

class tt(object):
    def __init__(self):
        pass

    def AA(self):
        self.name='Lucy'
    def tes(self):
        while True:
            cmd=input(">>:").strip()
            if hasattr(self,cmd): #用来判断对象object的属性(name表示)是否存在。
                print('Yes,we have fun %s'%cmd)
            else:
                print("nonono...,we don't have this fun")
obj=tt()
obj.tes()

运行结果：

>>:AA
Yes,we have fun AA
>>:test
nonono...,we don't have this fun
>>:b
nonono...,we don't have this fun
>>:

2. 自己写的

服务器端脚本

import socketserver,os,json
class MYTCP(socketserver.BaseRequestHandler): #定义一个请求处理类
    def handle(self): #重写handle函数
        while True:
            try:
                self.data=self.request.recv(1024)
                cmd_dic=json.loads(self.data.decode())
                action=cmd_dic['action']
                if hasattr(self,action):
                    func=getattr(self,action)
                    func(cmd_dic)
            except ConnectionResetError as e:
                print("Error is:",e)
                break

    def put(self,*args):
        cmd_dic=args[0]
        filename=cmd_dic['filename']
        filesize=cmd_dic['filesize']
        if os.path.isfile(filename): #如果服务器上已经存在，则建一个新的
            f=open(filename+'.new','wb')
        else:
            f=open(filename,'wb')
        self.request.send(b'be ready to receive')
        received_size=0
        while received_size<filesize:
            data=self.request.recv(1024)
            received_size+=len(data)
            f.write(data)
        else:
            f.close()
            print("upload successfully")

server=socketserver.ThreadingTCPServer(('localhost',9999),MYTCP) #实例化一个服务类
server.serve_forever() #调用服务类下面的serve_forever方法

客户端脚本：

import os,json,socket
class FtpClient(object):
    def __init__(self):
        self.client=socket.socket()
    def help(self):
        msg='''
        ls
        pwd
        cd..
        put filename
        get filename
        '''
        print(msg)
    def connect(self,ip,port):
        self.client.connect((ip,port))
    def interactive(self):
        while True:
            cmd=input(">>:").strip()
            if len(cmd)==0:continue
            cmd_str=cmd.split()[0]
            if hasattr(self,'cmd_%s'%cmd_str):
                func=getattr(self,'cmd_%s'%cmd_str)
                func(cmd)
            else:
                self.help()

    def cmd_put(self,*args):
        cmd_split=args[0].split()
        if len(cmd_split)>1:
            filename = cmd_split[1]
            if os.path.isfile(filename):
                filesize=os.stat(filename).st_size
                cmd_dic={
                    'action':'put',
                    'filename':filename,
                    'filesize':filesize,
                    'overridden':True
                }
                self.client.send(json.dumps(cmd_dic).encode())
                server_response=self.client.recv(1024)
                f=open(filename,'rb')
                for line in f:
                    self.client.send(line)
                else:
                    f.close()
                    print('upload successfully')

    def cmd_get(self,*args):
        pass
ftp=FtpClient()
ftp.connect('localhost',9999)
ftp.interactive()