telnetlib3 is a Telnet Client and Server library for python. This project requires python 3.7 and later, using the asyncio module.
Authoring a Telnet Server using Streams interface that offers a basic war game:
import asyncio, telnetlib3
async def shell(reader, writer):
writer.write('\r\nWould you like to play a game? ')
inp = await reader.read(1)
if inp:
writer.echo(inp)
writer.write('\r\nThey say the only way to win '
'is to not play at all.\r\n')
await writer.drain()
writer.close()
loop = asyncio.get_event_loop()
coro = telnetlib3.create_server(port=6023, shell=shell)
server = loop.run_until_complete(coro)
loop.run_until_complete(server.wait_closed())Authoring a Telnet Client that plays the war game with this server:
import asyncio, telnetlib3
async def shell(reader, writer):
while True:
# read stream until '?' mark is found
outp = await reader.read(1024)
if not outp:
# End of File
break
elif '?' in outp:
# reply all questions with 'y'.
writer.write('y')
# display all server output
print(outp, flush=True)
# EOF
print()
loop = asyncio.get_event_loop()
coro = telnetlib3.open_connection('localhost', 6023, shell=shell)
reader, writer = loop.run_until_complete(coro)
loop.run_until_complete(writer.protocol.waiter_closed)Two command-line scripts are distributed with this package.
telnetlib3-client
Small terminal telnet client. Some example destinations and options:
telnetlib3-client nethack.alt.org telnetlib3-client --encoding=cp437 --force-binary blackflag.acid.org telnetlib3-client htc.zapto.org
telnetlib3-server
Telnet server providing the default debugging shell. This provides a simple shell server that allows introspection of the session's values, for example:
tel:sh> help quit, writer, slc, toggle [option|all], reader, proto tel:sh> writer <TelnetWriter server mode:kludge +lineflow -xon_any +slc_sim server-will:BINARY,ECHO,SGA client-will:BINARY,NAWS,NEW_ENVIRON,TTYPE> tel:sh> reader <TelnetReaderUnicode encoding='utf8' limit=65536 buflen=0 eof=False> tel:sh> toggle all wont echo. wont suppress go-ahead. wont outbinary. dont inbinary. xon-any enabled. lineflow disabled. tel:sh> reader <TelnetReaderUnicode encoding='US-ASCII' limit=65536 buflen=1 eof=False> tel:sh> writer <TelnetWriter server mode:local -lineflow +xon_any +slc_sim client-will:NAWS,NEW_ENVIRON,TTYPE>
Both command-line scripts accept argument --shell=my_module.fn_shell
describing a python module path to a coroutine of signature
shell(reader, writer), just as the above examples.
The following RFC specifications are implemented:
- rfc-727, "Telnet Logout Option," Apr 1977.
- rfc-779, "Telnet Send-Location Option", Apr 1981.
- rfc-854, "Telnet Protocol Specification", May 1983.
- rfc-855, "Telnet Option Specifications", May 1983.
- rfc-856, "Telnet Binary Transmission", May 1983.
- rfc-857, "Telnet Echo Option", May 1983.
- rfc-858, "Telnet Suppress Go Ahead Option", May 1983.
- rfc-859, "Telnet Status Option", May 1983.
- rfc-860, "Telnet Timing mark Option", May 1983.
- rfc-885, "Telnet End of Record Option", Dec 1983.
- rfc-1073, "Telnet Window Size Option", Oct 1988.
- rfc-1079, "Telnet Terminal Speed Option", Dec 1988.
- rfc-1091, "Telnet Terminal-Type Option", Feb 1989.
- rfc-1096, "Telnet X Display Location Option", Mar 1989.
- rfc-1123, "Requirements for Internet Hosts", Oct 1989.
- rfc-1184, "Telnet Linemode Option (extended options)", Oct 1990.
- rfc-1372, "Telnet Remote Flow Control Option", Oct 1992.
- rfc-1408, "Telnet Environment Option", Jan 1993.
- rfc-1571, "Telnet Environment Option Interoperability Issues", Jan 1994.
- rfc-1572, "Telnet Environment Option", Jan 1994.
- rfc-2066, "Telnet Charset Option", Jan 1997.
Further documentation available at https://telnetlib3.readthedocs.org/