How to debug Twisted TLS with wireshark

debug.py

# 1. setup environment SSLKEYLOGFILE, value is a file path, I set it to /tmp/.ssl-key.log
# 2. put /tmp/.ssl-key.log to wireshark TLS pre-master key path
# 3. use following code, setup pyOpenSSL key log callback

certificateOptions = OpenSSLCertificateOptions(
    trustRoot=platformTrust(),
    acceptableProtocols=[b'h2'],
)
ctx = certificateOptions.getContext()


def append_to_key_log_file(key):
    log_file_path = os.getenv('SSLKEYLOGFILE')
    with open(log_file_path, 'ab+') as f:
        f.write(key + b'\n')


ctx.set_keylog_callback(lambda _, key: append_to_key_log_file(key))
options = ClientTLSOptions(AUTHORITY, ctx)
connectProtocol(
    SSL4ClientEndpoint(reactor, AUTHORITY, 443, options),
    H2Protocol()
)
reactor.run()