sm_echo_client.py

"""Sasi Mandava: echo_client.py 01/15/2017."""


import socket
import sys


def client(msg, log_buffer=sys.stderr):
    server_address = ('localhost', 10000)
    # TODO_COMPLETE: Replace the following line with your code which will instantiate
    #       a TCP socket with IPv4 Addressing, call the socket you make 'sock'
    sock = socket.socket(
                         socket.AF_INET,
                         socket.SOCK_STREAM,
                         socket.IPPROTO_TCP)
    print('connecting to {0} port {1}'.format(*server_address), file=log_buffer)
    # TODO_COMPLETE: connect your socket to the server here.
    sock.connect(server_address)

    # you can use this variable to accumulate the entire message received back
    # from the server
    # buffsize = 4096
    # received_message = b''
    # done = False
    # while not done:
    #     msg_part = sock.recv(buffsize)
    #     if len(msg_part) < buffsize:
    #         done = True
    #         sock.close()
    #     received_message += msg_part
    # print("entire_message", received_message)

    # this try/finally block exists purely to allow us to close the socket
    # when we are finished with it
    try:
        print('sending "{0}"'.format(msg), file=log_buffer)
        # TODO_COMPLETE: send your message to the server here.
        msg = msg.encode('utf8')
        sock.sendall(msg)

        # TODO_COMPLETE: the server should be sending you back your message as a series
        #       of 16-byte chunks. Accumulate the chunks you get to build the
        #       entire reply from the server. Make sure that you have received
        #       the entire message and then you can break the loop.
        #
        #       Log each chunk you receive.  Use the print statement below to
        #       do it. This will help in debugging problems
        received_message = b''
        done = False
        while not done:
            chunk_part = sock.recv(16)
            # print('received "{0}"'.format(chunk_part.decode('utf8')), file=log_buffer)
            if len(chunk_part) < 16:
                done = True
                # sock.close()
            received_message += chunk_part
        print('received "{0}"'.format(received_message.decode('utf8')), file=log_buffer)

        # print('received "{0}"'.format(chunk.decode('utf8')), file=log_buffer)
    finally:
        # TODO_COMPLETE: after you break out of the loop receiving echoed chunks from
        #       the server you will want to close your client socket.
        sock.close()
        print('closing socket', file=log_buffer)

        # TODO_COMPLETE: when all is said and done, you should return the entire reply
        # you received from the server as the return value of this function.
        # print("received_message:", received_message)
        return(received_message.decode('utf8'))


if __name__ == '__main__':
    if len(sys.argv) != 2:
        usage = '\nusage: python echo_client.py "this is my message"\n'
        print(usage, file=sys.stderr)
        sys.exit(1)

    msg = sys.argv[1]
    client(msg)