evennia/evennia/server/portal/websocket_client.py
2015-02-15 10:17:20 +01:00

156 lines
5 KiB
Python

"""
Websocket-webclient
This implements a webclient with WebSockets (http://en.wikipedia.org/wiki/WebSocket)
by use of the txws implementation (https://github.com/MostAwesomeDude/txWS). It is
used together with evennia/web/media/javascript/evennia_websocket_webclient.js.
Thanks to Ricard Pillosu whose Evennia plugin inspired this module.
Communication over the websocket interface is done with normal text
communication. A special case is OOB-style communication; to do this
the client must send data on the following form:
OOB{"func1":[args], "func2":[args], ...}
where the dict is JSON encoded. The initial OOB-prefix
is used to identify this type of communication, all other data
is considered plain text (command input).
Example of call from a javascript client:
websocket = new WeSocket("ws://localhost:8021")
var msg1 = "WebSocket Test"
websocket.send(msg1)
var msg2 = JSON.stringify({"testfunc":[[1,2,3], {"kwarg":"val"}]})
websocket.send("OOB" + msg2)
websocket.close()
"""
import json
from twisted.internet.protocol import Protocol
from evennia.server.session import Session
from evennia.utils.logger import log_trace
from evennia.utils.utils import to_str, make_iter
from evennia.utils.text2html import parse_html
class WebSocketClient(Protocol, Session):
"""
Implements the server-side of the Websocket connection.
"""
def connectionMade(self):
"""
This is called when the connection is first established.
"""
client_address = self.transport.client
self.init_session("websocket", client_address, self.factory.sessionhandler)
# watch for dead links
self.transport.setTcpKeepAlive(1)
self.sessionhandler.connect(self)
def disconnect(self, reason=None):
"""
generic hook for the engine to call in order to
disconnect this protocol.
"""
if reason:
self.data_out(text=reason)
self.connectionLost(reason)
def connectionLost(self, reason):
"""
this is executed when the connection is lost for
whatever reason. it can also be called directly, from
the disconnect method
"""
self.sessionhandler.disconnect(self)
self.transport.close()
def dataReceived(self, string):
"""
Method called when data is coming in over
the websocket connection.
Type of data is identified by a 3-character
prefix.
OOB - This is an Out-of-band instruction. If so,
the remaining string should be a json-packed
string on the form {oobfuncname: [args, ], ...}
CMD - plain text data, to be treated like a game
input command.
"""
mode = string[:3]
data = string[3:]
if mode == "OOB":
# an out-of-band command
self.decode_json(data)
elif mode == "CMD":
# plain text input
self.data_in(text=data)
def sendLine(self, line):
"send data to client"
return self.transport.write(line)
def json_decode(self, data):
"""
Decodes incoming data from the client
[cmdname, [args],{kwargs}] -> cmdname *args **kwargs
"""
try:
cmdname, args, kwargs = json.loads(data)
except Exception:
log_trace("Websocket malformed OOB request: %s" % data)
raise
self.sessionhandler.data_in(oob=(cmdname, args, kwargs))
def json_encode(self, cmdname, *args, **kwargs):
"""
Encode OOB data for sending to client
cmdname *args -> cmdname [json array]
cmdname **kwargs -> cmdname {json object}
"""
cmdtuple = [cmdname, list(args), kwargs]
self.sendLine("OOB" + json.dumps(cmdtuple))
def data_in(self, text=None, **kwargs):
"""
Data Websocket -> Server
"""
self.sessionhandler.data_in(self, text=text, **kwargs)
def data_out(self, text=None, **kwargs):
"""
Data Evennia -> Player.
generic hook method for engine to call in order to send data
through the websocket connection.
valid webclient kwargs:
oob=<string> - supply an Out-of-Band instruction.
raw=True - no parsing at all (leave ansi-to-html markers unparsed)
nomarkup=True - clean out all ansi/html markers and tokens
"""
try:
text = to_str(text if text else "", encoding=self.encoding)
except Exception, e:
self.sendLine(str(e))
if "oob" in kwargs:
for cmdname, args, okwargs in kwargs["oob"]:
self.encode_json(cmdname, *args, **okwargs)
raw = kwargs.get("raw", False)
nomarkup = kwargs.get("nomarkup", False)
if "prompt" in kwargs:
self.sendLine("PROMPT" + parse_html(kwargs["prompt"], strip_ansi=nomarkup))
if raw:
self.sendLine("CMD" + text)
else:
self.sendLine("CMD" + parse_html(text, strip_ansi=nomarkup))