Get CoAP messages from pcap files and create test messages for Python

parse_pcap_to_test_messages.py

#!/usr/bin/env python3
from pathlib import Path
import sys

import aiocoap
from aiocoap.optiontypes import StringOption
from scapy.contrib.coap import CoAP
from scapy.layers.inet import UDP
from scapy.utils import PcapReader

SCRIPT_DIR = Path(__file__).parent


def main(pcap_file: Path):
    a = PcapReader(str(pcap_file))
    code = "import aiocoap"

    a = [p for p in a if UDP in p and p.haslayer(CoAP)]
    for i, pkt in enumerate(a):
        c = pkt.getlayer(CoAP)

        code += f"\n# src: {pkt.src} dst: {pkt.dst}\n"
        aiocoap_msg = aiocoap.message.Message.decode(c.original)
        code += (
            f"msg_{i} = aiocoap.message.Message("
            f"mtype=aiocoap.message.Type.{aiocoap.numbers.types.Type(aiocoap_msg.mtype).name}, "
            f"code=aiocoap.message.Code.{aiocoap_msg.code.name}, payload={aiocoap_msg.payload})\n"
        )
        for j, opt in enumerate(aiocoap_msg.opt.option_list()):
            if type(opt) is StringOption:
                val = f'"{opt.value}"'
            else:
                val = opt.value
            code += (
                f"msg_{i}.opt.add_option("
                f"aiocoap.numbers.optionnumbers.OptionNumber.{opt.number.name}.create_option(value={val}))\n"
            )

    with open(SCRIPT_DIR / "coap_test_msgs.py", "w") as f:
        f.write(code)


if __name__ == "__main__":
    path = Path(sys.argv[1])
    main(path)