[BUG] Axmud is an unsupported client

Describe the bug

Axmud can’t connect to Evennia servers.

To Reproduce

Steps to reproduce the behavior:

1. Connect to the evdemo server
2. Get forcibly disconnected by Twisted

Additional context

I spent about twelve hours on this today, and here’s what I found:

• Axmud likes MSDP a lot. If it doesn’t get MSDP commands it likes, it sends IAC DONT MSDP
• Twisted doesn’t like IAC DONT MSDP at all after the handshake has already been “negotiated” - following are two common errors I got depending on how deep I got into overloading inputfuncs and rewriting telnet_oob. Note that the first OptionRefused error is \x22 (IAC DO LINEMODE) and the second is \x45 (IAC DO MSDP) Failure: twisted.conch.telnet.OptionRefused: twisted.conch.telnet.OptionRefused:b'"' Failure: twisted.conch.telnet.OptionRefused: twisted.conch.telnet.OptionRefused:b'E'
• Evennia seems to be receiving and decoding MSDP commands ok; functions are being called correctly; args are correct. This seems to be entirely centered around its handling of the handshake.
• I was actually able to reproduce a version of this bug in tintin; Evennia did not respond as expected when I sent IAC DO MSDP. The handshake appeared not to happen, and #send {$IAC$DO$MSDP} as an event on IAC WILL MSDP didn’t seem to work either. But tintin maintained the connection without issue.
• A raw dump of the telnet events looks perfect: TELNET_EVENT: p1[253] p2[34] p3[��"] (IAC DO LINEMODE) TELNET_EVENT: p1[251] p2[3] p3[��] (IAC DO ...) TELNET_EVENT: p1[253] p2[31] p3[��] (IAC DO ...) TELNET_EVENT: p1[253] p2[24] p3[��] (IAC DO ...) TELNET_EVENT: p1[251] p2[86] p3[��V] (IAC DO ...) TELNET_EVENT: p1[251] p2[70] p3[��F] (IAC DO MSSP) TELNET_EVENT: p1[251] p2[69] p3[��E] (IAC DO MSDP)
• Bug verified on latest commit (1-29-20)
• All other handshakes work beautifully on all clients. I’m stumped as to why Axmud falls on its sword when it’s supposedly one of the “more modern” clients available.

[axcore]

If it’s helpful, Axmud can show the MSDP data it’s receiving.

Connect to any world, in online or offline mode Edit > Axmud preferences… > Settings > Page 9 Select Show debug messages while negotiating telnet options/MUD protocols Select Show short debug messages while negotiating telnet options/MUD protocols Click OK to close the window Type ;save Reconnect to Evennia

[Griatch]

@trhr Thanks for the help, but no need to spend more time - I have fixed this, just looking into some other cleanup now before committing a fix. And you are correct i that this is a py2->py3 issue.