====== Python ソケット プログラミング ======

===== Python で Wake on LAN のマジックパケットを送信する =====
[[wpjp>Wake-on-LAN|Wake-on-LAN - Wikipedia]]\\

<WRAP prewrap 100% #mincode>
<code python>
#!/usr/bin/env python3
# -*- coding: utf-8 -*-
import argparse
import socket
import struct
from traceback import print_exc

DEFAULT_PORT = 7 # 7 or 9 or 30000 ?
#BROADCAST_IPADDR = '<broadcast>'
BROADCAST_IPADDR = '255.255.255.255'

def send_magic_packet(mac_addr, port=DEFAULT_PORT):
    # create socket
    with socket.socket(socket.AF_INET, socket.SOCK_DGRAM) as sock:
        sock.setsockopt(socket.SOL_SOCKET, socket.SO_BROADCAST, 1)
        # parse address
        wol_mac = mac_addr.upper().replace('-', '').replace(':', '')
        if len(wol_mac) != 12:
            raise Exception('invalid MAC address format: {}'.format(mac_addr))
        buf = b'f' * 2 * 6 + (wol_mac * 16).encode()
        # encode to magic packet payload
        magic_packet = b''
        for i in range(0, len(buf), 2):
            magic_packet += struct.pack('B', int(buf[i:i + 2], 16))

        # send magic packet
        print('Sending magic packet for: {}, broadcast port is {} ...'.format(mac_addr, port))
        sock.sendto(magic_packet, (BROADCAST_IPADDR, port))

def parse_args():
    parser = argparse.ArgumentParser()
    parser.add_argument('mac_address', help='Target MAC address.', type=str)
    parser.add_argument('-p', '--port',
                        help='Default broadcast port is {}.'.format(DEFAULT_PORT),
                        default=DEFAULT_PORT, type=int)
    return parser.parse_args()

def main():
    args = parse_args()
    mac_addr = args.mac_address
    port = args.port

    try:
        #mac_addr = "AA:BB:CC:DD:EE:FF"
        send_magic_packet(mac_addr, port)

    except BaseException:
        print_exc()

if __name__ == '__main__':
    main()
</code>
</WRAP>

**実行例:**\\
<WRAP prewrap 100%>
<code powershell>
$ python wol.py
</code>
</WRAP>
<WRAP prewrap 100% #result>
<code powershell>
usage: wol.py [-h] [-p port] mac_address
wol.py: error: the following arguments are required: mac_address
</code>
</WRAP>

<WRAP prewrap 100%>
<code powershell>
$ python wol.py -h
</code>
</WRAP>
<WRAP prewrap 100% #result>
<code powershell>
usage: wol.py [-h] [-p port] mac_address

positional arguments:
  mac_address           Target MAC address.

optional arguments:
  -h, --help            show this help message and exit
  -p port, --port port  Default broadcast port is 7.
</code>
</WRAP>

ターゲットの MAC address にマジックパケットを送信する。\\
<WRAP prewrap 100%>
<code powershell>
$ python wol.py 68:96:7b:07:21:55
</code>
</WRAP>
ターゲットの PC が起動する。\\
<WRAP prewrap 100% #result>
<code powershell>
Sending magic packet for: 68:96:7B:07:21:55, broadcast port is 7 ...
</code>
</WRAP>

===== 参考文献 =====
[[https://kapibara-sos.net/archives/853|PythonでWake-on-lan]]\\
[[https://emptypage.jp/gadgets/wol.html|wol.py]]\\
[[http://e-words.jp/w/%E3%83%9E%E3%82%B8%E3%83%83%E3%82%AF%E3%83%91%E3%82%B1%E3%83%83%E3%83%88.html|マジックパケットとは - IT用語辞典 e-Words]]\\
[[https://www.atmarkit.co.jp/ait/articles/2004/20/news021.html|【リモートワーク自由自在】Windows 10 Wake On LAN（WoL）入門 (1/2)：WoLでPCを起動 - ＠IT]]\\