#####################################################################################
#
# Copyright (c) typedef int GmbH
# SPDX-License-Identifier: EUPL-1.2
#
#####################################################################################
import json
from collections import deque
from autobahn.util import _LazyHexFormatter, generate_token
from autobahn.wamp.exception import SerializationError, TransportLost
from autobahn.wamp.websocket import parseSubprotocolIdentifier
# Each of the following 2 trigger a reactor import at module level
# See https://twistedmatrix.com/trac/ticket/8246 for fixing it
from twisted.web import http
from twisted.web.resource import NoResource, Resource
from twisted.web.server import NOT_DONE_YET
from txaio import create_failure, failure_format_traceback, failure_message, make_logger
__all__ = ("WampLongPollResource",)
class WampLongPollResourceSessionSend(Resource):
"""
A Web resource for sending via XHR that is part of :class:`autobahn.twisted.longpoll.WampLongPollResourceSession`.
"""
log = make_logger()
def __init__(self, parent):
"""
:param parent: The Web parent resource for the WAMP session.
:type parent: Instance of :class:`autobahn.twisted.longpoll.WampLongPollResourceSession`.
"""
Resource.__init__(self)
self._parent = parent
def render_POST(self, request):
"""
A client sends a message via WAMP-over-Longpoll by HTTP/POSTing
to this Web resource. The body of the POST should contain a batch
of WAMP messages which are serialized according to the selected
serializer, and delimited by a single ``\0`` byte in between two WAMP
messages in the batch.
"""
payload = request.content.read()
self.log.debug(
"WampLongPoll: receiving data for transport '{tid}'\n{octets}",
tid=self._parent._transport_id,
octets=_LazyHexFormatter(payload),
)
try:
# process (batch of) WAMP message(s)
self._parent.onMessage(payload, None)
except Exception:
f = create_failure()
self.log.error(
"Could not unserialize WAMP message: {msg}",
msg=failure_message(f),
)
self.log.debug("{tb}", tb=failure_format_traceback(f))
return self._parent._parent._fail_request(request, b"could not unserialize WAMP message.")
else:
request.setResponseCode(http.NO_CONTENT)
self._parent._parent._set_standard_headers(request)
self._parent._isalive = True
return b""
class WampLongPollResourceSessionReceive(Resource):
"""
A Web resource for receiving via XHR that is part of :class:`autobahn.twisted.longpoll.WampLongPollResourceSession`.
"""
log = make_logger()
def __init__(self, parent):
"""
:param parent: The Web parent resource for the WAMP session.
:type parent: Instance of :class:`autobahn.twisted.longpoll.WampLongPollResourceSession`.
"""
Resource.__init__(self)
self._parent = parent
self.reactor = self._parent._parent.reactor
self._queue = deque()
self._request = None
self._killed = False
# FIXME: can we read the loglevel from self.log currently set?
if False:
def logqueue():
if not self._killed:
self.log.debug(
"WampLongPoll: transport '{tid}' - currently polled {is_polled}, pending messages {pending}",
tid=self._parent._transport_id,
is_polled=self._request is not None,
pending=len(self._queue),
)
self.reactor.callLater(1, logqueue)
logqueue()
def queue(self, data):
"""
Enqueue data to be received by client.
:param data: The data to be received by the client.
:type data: bytes
"""
self._queue.append(data)
self._trigger()
def _kill(self):
"""
Kill any outstanding request.
"""
if self._request:
self._request.finish()
self._request = None
self._killed = True
def _trigger(self):
"""
Trigger batched sending of queued messages.
"""
if self._request and len(self._queue):
if self._parent._serializer._serializer._batched:
# in batched mode, write all pending messages
while len(self._queue) > 0:
msg = self._queue.popleft()
self._request.write(msg)
else:
# in unbatched mode, only write 1 pending message
msg = self._queue.popleft()
if isinstance(msg, bytes):
self._request.write(msg)
else:
self.log.error(
"internal error: cannot write data of type {type_} - {msg}",
type_=type(msg),
msg=msg,
)
self._request.finish()
self._request = None
def render_POST(self, request):
"""
A client receives WAMP messages by issuing a HTTP/POST to this
Web resource. The request will immediately return when there are
messages pending to be received. When there are no such messages
pending, the request will "just hang", until either a message
arrives to be received or a timeout occurs.
"""
# remember request, which marks the session as being polled
self._request = request
self._parent._parent._set_standard_headers(request)
mime_type = self._parent._serializer.MIME_TYPE
if isinstance(mime_type, str):
mime_type = mime_type.encode("utf8")
request.setHeader(b"content-type", mime_type)
def cancel(_):
self.log.debug(
"WampLongPoll: poll request for transport '{tid}' has gone away",
tid=self._parent._transport_id,
)
self._request = None
request.notifyFinish().addErrback(cancel)
self._parent._isalive = True
self._trigger()
return NOT_DONE_YET
class WampLongPollResourceSessionClose(Resource):
"""
A Web resource for closing the Long-poll session WampLongPollResourceSession.
"""
log = make_logger()
def __init__(self, parent):
"""
:param parent: The Web parent resource for the WAMP session.
:type parent: Instance of :class:`autobahn.twisted.longpoll.WampLongPollResourceSession`.
"""
Resource.__init__(self)
self._parent = parent
def render_POST(self, request):
"""
A client may actively close a session (and the underlying long-poll transport)
by issuing a HTTP/POST with empty body to this resource.
"""
self.log.debug(
"WampLongPoll: closing transport '{tid}'",
tid=self._parent._transport_id,
)
# now actually close the session
self._parent.close()
self.log.debug(
"WampLongPoll: session ended and transport {tid} closed",
tid=self._parent._transport_id,
)
request.setResponseCode(http.NO_CONTENT)
self._parent._parent._set_standard_headers(request)
return b""
class WampLongPollResourceSession(Resource):
"""
A Web resource representing an open WAMP session.
"""
log = make_logger()
def __init__(self, parent, transport_details):
"""
Create a new Web resource representing a WAMP session.
:param parent: The parent Web resource.
:type parent: Instance of :class:`autobahn.twisted.longpoll.WampLongPollResource`.
:param transport_details: Details on the WAMP-over-Longpoll transport session.
:type transport_details: dict
"""
Resource.__init__(self)
self._parent = parent
self.reactor = self._parent.reactor
self._transport_details = transport_details
self._transport_id = transport_details["transport"]
self._serializer = transport_details["serializer"]
self._session = None
# session authentication information
#
self._authid = None
self._authrole = None
self._authmethod = None
self._authprovider = None
self._send = WampLongPollResourceSessionSend(self)
self._receive = WampLongPollResourceSessionReceive(self)
self._close = WampLongPollResourceSessionClose(self)
self.putChild(b"send", self._send)
self.putChild(b"receive", self._receive)
self.putChild(b"close", self._close)
self._isalive = False
# kill inactive sessions after this timeout
#
killAfter = self._parent._killAfter
if killAfter > 0:
def killIfDead():
if not self._isalive:
self.log.debug(
"WampLongPoll: killing inactive WAMP session with transport '{tid}'",
tid=self._transport_id,
)
self.onClose(False, 5000, "session inactive")
self._receive._kill()
if self._transport_id in self._parent._transports:
del self._parent._transports[self._transport_id]
else:
self.log.debug(
"WampLongPoll: transport '{tid}' is still alive",
tid=self._transport_id,
)
self._isalive = False
self.reactor.callLater(killAfter, killIfDead)
self.reactor.callLater(killAfter, killIfDead)
else:
self.log.debug(
"WampLongPoll: transport '{tid}' automatic killing of inactive session disabled",
tid=self._transport_id,
)
self.log.debug(
"WampLongPoll: session resource for transport '{tid}' initialized)",
tid=self._transport_id,
)
self.onOpen()
def render_GET(self, request):
self._parent._set_standard_headers(request)
res = {"transport": self._transport_id, "session": self._session._session_id if self._session else None}
return json.dumps(res).encode()
def close(self):
"""
Implements :func:`autobahn.wamp.interfaces.ITransport.close`
"""
if self.isOpen():
self.onClose(True, 1000, "session closed")
self._receive._kill()
del self._parent._transports[self._transport_id]
else:
raise TransportLost()
def abort(self):
"""
Implements :func:`autobahn.wamp.interfaces.ITransport.abort`
"""
if self.isOpen():
self.onClose(True, 1000, "session aborted")
self._receive._kill()
del self._parent._transports[self._transport_id]
else:
raise TransportLost()
# noinspection PyUnusedLocal
def onClose(self, wasClean, code, reason):
"""
Callback from :func:`autobahn.websocket.interfaces.IWebSocketChannel.onClose`
"""
if self._session:
try:
self._session.onClose(wasClean)
except Exception:
# ignore exceptions raised here, but log ..
self.log.failure("invoking session's onClose failed")
self._session = None
def onOpen(self):
"""
Callback from :func:`autobahn.websocket.interfaces.IWebSocketChannel.onOpen`
"""
self._session = self._parent._factory()
# noinspection PyBroadException
try:
self._session.onOpen(self)
except Exception:
# ignore exceptions raised here, but log ..
self.log.failure("Invoking session's onOpen failed")
def onMessage(self, payload, isBinary):
"""
Callback from :func:`autobahn.websocket.interfaces.IWebSocketChannel.onMessage`
"""
for msg in self._serializer.unserialize(payload, isBinary):
self.log.debug(
"WampLongPoll: RX {octets}",
octets=_LazyHexFormatter(msg),
)
self._session.onMessage(msg)
def send(self, msg):
"""
Implements :func:`autobahn.wamp.interfaces.ITransport.send`
"""
if self.isOpen():
try:
self.log.debug(
"WampLongPoll: TX {octets}",
octets=_LazyHexFormatter(msg),
)
payload, isBinary = self._serializer.serialize(msg)
except Exception as e:
# all exceptions raised from above should be serialization errors ..
f = create_failure()
self.log.error(
"Unable to serialize WAMP application payload: {msg}",
msg=failure_message(f),
)
self.log.debug("{tb}", tb=failure_format_traceback(f))
raise SerializationError("unable to serialize WAMP application payload ({0})".format(e))
else:
self._receive.queue(payload)
else:
raise TransportLost()
def isOpen(self):
"""
Implements :func:`autobahn.wamp.interfaces.ITransport.isOpen`
"""
return self._session is not None
class WampLongPollResourceOpen(Resource):
"""
A Web resource for creating new WAMP sessions.
"""
log = make_logger()
def __init__(self, parent):
"""
:param parent: The parent Web resource.
:type parent: Instance of :class:`autobahn.twisted.longpoll.WampLongPollResource`.
"""
Resource.__init__(self)
self._parent = parent
def render_POST(self, request):
"""
Request to create a new WAMP session.
"""
self.log.debug("WampLongPoll: creating new session ..")
payload = request.content.read().decode("utf8")
try:
options = json.loads(payload)
except Exception:
f = create_failure()
self.log.error(
"Couldn't parse WAMP request body: {msg}",
msg=failure_message(f),
)
self.log.debug("{msg}", msg=failure_format_traceback(f))
return self._parent._fail_request(request, b"could not parse WAMP session open request body")
if not isinstance(options, dict):
return self._parent._fail_request(request, b"invalid type for WAMP session open request")
if "protocols" not in options:
return self._parent._fail_request(request, "missing attribute 'protocols' in WAMP session open request")
# determine the protocol to speak
#
protocol = None
serializer = None
for p in options["protocols"]:
version, serializerId = parseSubprotocolIdentifier(p)
if version == 2 and serializerId in self._parent._serializers.keys():
serializer = self._parent._serializers[serializerId]
protocol = p
break
if protocol is None:
return self._fail_request(
request,
b"no common protocol to speak (I speak: {0})".format(
["wamp.2.{0}".format(s) for s in self._parent._serializers.keys()]
),
)
# make up new transport ID
#
if self._parent._debug_transport_id:
# use fixed transport ID for debugging purposes
transport = self._parent._debug_transport_id
else:
transport = generate_token(1, 12)
# this doesn't contain all the info (when a header key appears multiple times)
# http_headers_received = request.getAllHeaders()
http_headers_received = {}
for key, values in request.requestHeaders.getAllRawHeaders():
if key not in http_headers_received:
http_headers_received[key] = []
http_headers_received[key].extend(values)
transport_details = {
"transport": transport,
"serializer": serializer,
"protocol": protocol,
"peer": request.getClientIP(),
"http_headers_received": http_headers_received,
"http_headers_sent": None,
}
# create instance of WampLongPollResourceSession or subclass thereof ..
#
self._parent._transports[transport] = self._parent.protocol(self._parent, transport_details)
# create response
#
self._parent._set_standard_headers(request)
request.setHeader(b"content-type", b"application/json; charset=utf-8")
result = {"transport": transport, "protocol": protocol}
self.log.debug(
"WampLongPoll: new session created on transport '{transport}'".format(
transport=transport,
)
)
payload = json.dumps(result)
return payload.encode()
[docs]
class WampLongPollResource(Resource):
"""
A WAMP-over-Longpoll resource for use with Twisted Web Resource trees.
This class provides an implementation of the WAMP-over-Longpoll transport
for WAMP.
The Resource exposes the following paths (child resources).
Opening a new WAMP session:
* ``<base-url>/open``
Once a transport is created and the session is opened:
* ``<base-url>/<transport-id>/send``
* ``<base-url>/<transport-id>/receive``
* ``<base-url>/<transport-id>/close``
"""
[docs]
protocol = WampLongPollResourceSession
def __init__(
self,
factory,
serializers=None,
timeout=10,
killAfter=30,
queueLimitBytes=128 * 1024,
queueLimitMessages=100,
debug_transport_id=None,
reactor=None,
):
"""
Create new HTTP WAMP Web resource.
:param factory: A (router) session factory.
:type factory: Instance of :class:`autobahn.twisted.wamp.RouterSessionFactory`.
:param serializers: List of WAMP serializers.
:type serializers: list of obj (which implement :class:`autobahn.wamp.interfaces.ISerializer`)
:param timeout: XHR polling timeout in seconds.
:type timeout: int
:param killAfter: Kill WAMP session after inactivity in seconds.
:type killAfter: int
:param queueLimitBytes: Kill WAMP session after accumulation of this many bytes in send queue (XHR poll).
:type queueLimitBytes: int
:param queueLimitMessages: Kill WAMP session after accumulation of this many message in send queue (XHR poll).
:type queueLimitMessages: int
:param debug: Enable debug logging.
:type debug: bool
:param debug_transport_id: If given, use this fixed transport ID.
:type debug_transport_id: str
:param reactor: The Twisted reactor to run under.
:type reactor: obj
"""
Resource.__init__(self)
# RouterSessionFactory
[docs]
self._factory = factory
# lazy import to avoid reactor install upon module import
if reactor is None:
from twisted.internet import reactor
[docs]
self._debug_transport_id = debug_transport_id
[docs]
self._timeout = timeout
[docs]
self._killAfter = killAfter
[docs]
self._queueLimitBytes = queueLimitBytes
[docs]
self._queueLimitMessages = queueLimitMessages
if serializers is None:
serializers = []
# try CBOR WAMP serializer
try:
from autobahn.wamp.serializer import CBORSerializer
serializers.append(CBORSerializer(batched=True))
serializers.append(CBORSerializer())
except ImportError:
pass
# try MsgPack WAMP serializer
try:
from autobahn.wamp.serializer import MsgPackSerializer
serializers.append(MsgPackSerializer(batched=True))
serializers.append(MsgPackSerializer())
except ImportError:
pass
# try UBJSON WAMP serializer
try:
from autobahn.wamp.serializer import UBJSONSerializer
serializers.append(UBJSONSerializer(batched=True))
serializers.append(UBJSONSerializer())
except ImportError:
pass
# try JSON WAMP serializer
try:
from autobahn.wamp.serializer import JsonSerializer
serializers.append(JsonSerializer(batched=True))
serializers.append(JsonSerializer())
except ImportError:
pass
if not serializers:
raise Exception("could not import any WAMP serializers")
for ser in serializers:
self._serializers[ser.SERIALIZER_ID] = ser
# <Base URL>/open
#
self.putChild(b"open", WampLongPollResourceOpen(self))
self.log.debug("WampLongPollResource initialized")
[docs]
def render_GET(self, request):
request.setHeader(b"content-type", b"text/html; charset=UTF-8")
peer = b"{0}:{1}".format(request.client.host, request.client.port)
return self._get_notice(peer=peer)
[docs]
def getChild(self, name, request):
"""
Returns send/receive/close resource for transport.
.. seealso::
* :class:`twisted.web.resource.Resource`
* :class:`zipfile.ZipFile`
"""
name = name.decode("utf8")
if name not in self._transports:
if not name:
return self
else:
self.log.error("No WAMP transport '{name}'", name=name)
return NoResource("no WAMP transport '{0}'".format(name))
if len(request.postpath) == 0 or (
len(request.postpath) == 1 and request.postpath[0] in [b"send", b"receive", b"close"]
):
return self._transports[name]
else:
return NoResource("invalid WAMP transport operation '{0}'".format(request.postpath))
[docs]
def _set_standard_headers(self, request):
"""
Set standard HTTP response headers.
"""
origin = request.getHeader(b"origin")
if origin is None or origin == b"null":
origin = b"*"
request.setHeader(b"access-control-allow-origin", origin)
request.setHeader(b"access-control-allow-credentials", b"true")
request.setHeader(b"cache-control", b"no-store, no-cache, must-revalidate, max-age=0")
headers = request.getHeader(b"access-control-request-headers")
if headers is not None:
request.setHeader(b"access-control-allow-headers", headers)
[docs]
def _fail_request(self, request, msg):
"""
Fails a request to the long-poll service.
"""
self._set_standard_headers(request)
request.setHeader(b"content-type", b"text/plain; charset=UTF-8")
request.setResponseCode(http.BAD_REQUEST)
return msg
[docs]
def _get_notice(self, peer, redirect_url=None, redirect_after=0):
"""
Render a user notice (HTML page) when the Long-Poll root resource
is accessed via HTTP/GET (by a user).
:param redirect_url: Optional URL to redirect the user to.
:type redirect_url: str
:param redirect_after: When ``redirect_url`` is provided, redirect after this time (seconds).
:type redirect_after: int
"""
if redirect_url:
redirect = b"""<meta http-equiv="refresh" content="{};URL='{}'">""".format(redirect_after, redirect_url)
else:
redirect = b""
html = b"""
<!DOCTYPE html>
<html>
<head>
%s
<style>
body {
color: #333;
background-color: #ffde00;
font-family: "Segoe UI", "Lucida Grande", "Helvetica Neue", Helvetica, Arial, sans-serif;
font-size: 16px;
}
a, a:visited, a:hover {
color: #333;
}
</style>
</head>
<body>
<h1>Crossbar.io</h1>
<p>I am not Web server, but a <b>WAMP-over-Longpoll</b> listening transport.</p>
</body>
</html>
""" % (redirect,)
return html