python sendfile_client.py

Posted 2021-05-09

import socket, select, string, sys, os
 
def prompt() :
    sys.stdout.write('\n<You> ')
    sys.stdout.flush()
 
if __name__ == "__main__":
    # define server's name and port
    host = 'localhost'
    port = 5000

    RECV_BUFFER = 1024

    # create client socket
    s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
    s.settimeout(2)
     
    # connect to remote host
    try :
        s.connect((host, port))
    except :
        print '  > Unable to connect'
        sys.exit()
    
    command = '*'
    buf = ''     
    print '  > Connected to remote server'
    prompt()
     
    while 1:
        socket_list = [sys.stdin, s]
         
        # Get the list sockets which are readable
        read_sockets, write_sockets, error_sockets = select.select(socket_list , [], [])
         
        for sock in read_sockets:
            #incoming message from server
            if sock == s:
                data = sock.recv(RECV_BUFFER)
                if not data :
                    print '\nDisconnected from server'
                    sys.exit()
                elif data == 'File not found' :
                    print '\n  > File not found'
                    prompt()
                elif data == 'Command not found' :
                    print '\n  > Command not found'
                    prompt()
                else :                 
                    # get message header
                    message_header = data.partition('\n\n\n')
                    
                    # get file size from message header
                    file_size = message_header[0].partition('file_size: ')
                    size = int(file_size[2])+len(message_header[0])+len(message_header[1])
                    
                    # receive data from server
                    buf = data
                    print '  > Download : ',
                    while len(buf) < size:
                        print '......',
                        data = sock.recv(RECV_BUFFER)
                        buf += data
                    print ''
                    # get file name from last command
                    protocol = command.partition(" ")

                    # check if file already exist (delete if exist)
                    if os.path.exists(protocol[2]):
                        os.remove(protocol[2])

                    # get data file without message header
                    data_file = buf.partition('\n\n\n')

                    # write buffer data to new file
                    with open(protocol[2], 'wb') as file:
                        file.write(data_file[2])

                    # display message header
                    print '\nMessage Header :'
                    print message_header[0]
                    print ""

                    #close file after write
                    file.close()
                    print "  > Download finish :)"
                    prompt()
            #user entered a message
            else :
                msg = raw_input()
                command = msg
                s.send(msg)