########################################################################
# File name: node.py
# This file is part of: aioxmpp
#
# LICENSE
#
# This program is free software: you can redistribute it and/or modify
# it under the terms of the GNU Lesser General Public License as
# published by the Free Software Foundation, either version 3 of the
# License, or (at your option) any later version.
#
# This program is distributed in the hope that it will be useful, but
# WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
# Lesser General Public License for more details.
#
# You should have received a copy of the GNU Lesser General Public
# License along with this program. If not, see
# <http://www.gnu.org/licenses/>.
#
########################################################################
"""
:mod:`~aioxmpp.node` --- XMPP network nodes (clients, mostly)
#############################################################
This module contains functions to connect to an XMPP server, as well as
maintaining the stream. In addition, a client class which completely manages a
stream based on a presence setting is provided.
Using XMPP
==========
.. currentmodule:: aioxmpp
.. autoclass:: Client
.. autoclass:: PresenceManagedClient
.. currentmodule:: aioxmpp.node
.. class:: AbstractClient
Alias of :class:`Client`.
.. deprecated:: 0.8
The alias will be removed in 1.0.
Connecting streams low-level
============================
.. autofunction:: discover_connectors
.. autofunction:: connect_xmlstream
Utilities
=========
.. autoclass:: UseConnected
"""
import asyncio
import contextlib
import logging
import warnings
from datetime import timedelta
import dns.resolver
import aiosasl
from . import (
connector,
network,
protocol,
errors,
stream,
callbacks,
nonza,
rfc3921,
rfc6120,
stanza,
structs,
security_layer,
presence as mod_presence,
)
from .utils import namespaces
logger = logging.getLogger(__name__)
def lookup_addresses(loop, jid):
addresses = yield from network.find_xmpp_host_addr(
loop,
jid.domain)
return network.group_and_order_srv_records(addresses)
@asyncio.coroutine
[docs]def discover_connectors(domain, loop=None, logger=logger):
"""
Discover all connection options for a domain, in descending order of
preference.
This coroutine returns options discovered from SRV records, or if none are
found, the generic option using the domain name and the default XMPP client
port.
Each option is represented by a triple ``(host, port, connector)``.
`connector` is a :class:`aioxmpp.connector.BaseConnector` instance which is
suitable to connect to the given host and port.
`logger` is the logger used by the function.
The following sources are supported:
* :rfc:`6120` SRV records. One option is returned per SRV record.
If one of the SRV records points to the root name (``.``),
:class:`ValueError` is raised (the domain specifically said that XMPP is
not supported here).
* :xep:`368` SRV records. One option is returned per SRV record.
* :rfc:`6120` fallback process (only if no SRV records are found). One
option is returned for the host name with the default XMPP client port.
The options discovered from SRV records are mixed together, ordered by
priority and then within priorities are shuffled according to their weight.
Thus, if there are multiple records of equal priority, the result of the
function is not deterministic.
.. versionadded:: 0.6
"""
try:
starttls_srv_records = yield from network.lookup_srv(
domain,
"xmpp-client",
)
starttls_srv_disabled = False
except ValueError:
starttls_srv_records = []
starttls_srv_disabled = True
try:
tls_srv_records = yield from network.lookup_srv(
domain,
"xmpps-client",
)
tls_srv_disabled = False
except ValueError:
tls_srv_records = []
tls_srv_disabled = True
if starttls_srv_disabled and (tls_srv_disabled or tls_srv_records is None):
raise ValueError(
"XMPP not enabled on domain {!r}".format(domain),
)
if starttls_srv_records is None and tls_srv_records is None:
# no SRV records published, fall back
logger.debug(
"no SRV records found for %s, falling back",
domain,
)
return [
(domain, 5222, connector.STARTTLSConnector()),
]
starttls_srv_records = starttls_srv_records or []
tls_srv_records = tls_srv_records or []
srv_records = [
(prio, weight, (host, port, connector.STARTTLSConnector()))
for prio, weight, (host, port) in starttls_srv_records
]
srv_records.extend(
(prio, weight, (host, port, connector.XMPPOverTLSConnector()))
for prio, weight, (host, port) in tls_srv_records
)
options = list(
network.group_and_order_srv_records(srv_records)
)
logger.debug(
"options for %s: %r",
domain,
options,
)
return options
@asyncio.coroutine
def _try_options(options, exceptions,
jid, metadata, negotiation_timeout, loop, logger):
"""
Helper function for :func:`connect_xmlstream`.
"""
for host, port, conn in options:
logger.debug(
"domain %s: trying to connect to %r:%s using %r",
jid.domain, host, port, conn
)
try:
transport, xmlstream, features = yield from conn.connect(
loop,
metadata,
jid.domain,
host,
port,
negotiation_timeout,
)
except OSError as exc:
logger.warning(
"connection failed: %s", exc
)
exceptions.append(exc)
continue
logger.debug(
"domain %s: connection succeeded using %r",
jid.domain,
conn,
)
try:
features = yield from security_layer.negotiate_sasl(
transport,
xmlstream,
metadata.sasl_providers,
negotiation_timeout,
jid,
features,
)
except errors.SASLUnavailable as exc:
protocol.send_stream_error_and_close(
xmlstream,
condition=(namespaces.streams, "policy-violation"),
text=str(exc),
)
exceptions.append(exc)
continue
except Exception as exc:
protocol.send_stream_error_and_close(
xmlstream,
condition=(namespaces.streams, "undefined-condition"),
text=str(exc),
)
raise
return transport, xmlstream, features
return None
@asyncio.coroutine
[docs]def connect_xmlstream(
jid,
metadata,
negotiation_timeout=60.,
override_peer=[],
loop=None,
logger=logger):
"""
Prepare and connect a :class:`aioxmpp.protocol.XMLStream` to a server
responsible for the given `jid` and authenticate against that server using
the SASL mechansims described in `metadata`.
:param jid: Address of the user for which the connection is made.
:type jid: :class:`aioxmpp.JID`
:param metadata: Connection metadata for configuring the TLS usage.
:type metadata: :class:`~.security_layer.SecurityLayer`
:param negotiation_timeout: Timeout for each individual negotiation step.
:type negotiation_timeout: :class:`float` in seconds
:param override_peer: Sequence of connection options which take precedence
over normal discovery methods.
:type override_peer: sequence of (:class:`str`, :class:`int`,
:class:`~.BaseConnector`) triples
:param loop: asyncio event loop to use (defaults to current)
:type loop: :class:`asyncio.BaseEventLoop`
:param logger: Logger to use (defaults to module-wide logger)
:type logger: :class:`logging.Logger`
:raises ValueError: if the domain from the `jid` announces that XMPP is not
supported at all.
:raises aioxmpp.errors.TLSFailure: if all connection attempts fail and one
of them is a :class:`~.TLSFailure`.
:raises aioxmpp.errors.MultiOSError: if all connection attempts fail.
:return: Transport, XML stream and the current stream features
:rtype: tuple of (:class:`asyncio.BaseTransport`, :class:`~.XMLStream`,
:class:`~.nonza.StreamFeatures`)
The part of the `metadata` specifying the use of TLS is applied. If the
security layer does not mandate TLS, the resulting XML stream may not be
using TLS. TLS is used whenever possible.
The connection options in `override_peer` are tried before any standardised
discovery of connection options is made. Only if all of them fail,
automatic discovery of connection options is performed.
`loop` may be a :class:`asyncio.BaseEventLoop` to use. Defaults to the
current event loop.
If the domain from the `jid` announces that XMPP is not supported at all,
:class:`ValueError` is raised. If no options are returned from
:func:`discover_connectors` and `override_peer` is empty,
:class:`ValueError` is raised, too.
If all connection attempts fail, :class:`aioxmpp.errors.MultiOSError` is
raised. The error contains one exception for each of the options discovered
as well as the elements from `override_peer` in the order they were tried.
A TLS problem is treated like any other connection problem and the other
connection options are considered. However, if *all* connection options
fail and the set of encountered errors includes a TLS error, the TLS error
is re-raised instead of raising a :class:`aioxmpp.errors.MultiOSError`.
Return a triple ``(transport, xmlstream, features)``. `transport`
the underlying :class:`asyncio.Transport` which is used for the `xmlstream`
:class:`~.protocol.XMLStream` instance. `features` is the
:class:`aioxmpp.nonza.StreamFeatures` instance describing the features of
the stream.
.. versionadded:: 0.6
.. versionchanged:: 0.8
The explicit raising of TLS errors has been introduced. Before, TLS
errors were treated like any other connection error, possibly masking
configuration problems.
"""
loop = asyncio.get_event_loop() if loop is None else loop
domain = jid.domain.encode("idna")
options = list(override_peer)
exceptions = []
result = yield from _try_options(
options,
exceptions,
jid, metadata, negotiation_timeout, loop, logger,
)
if result is not None:
return result
options = list((yield from discover_connectors(
domain,
loop=loop,
logger=logger,
)))
result = yield from _try_options(
options,
exceptions,
jid, metadata, negotiation_timeout, loop, logger,
)
if result is not None:
return result
if not options and not override_peer:
raise ValueError("no options to connect to XMPP domain {!r}".format(
jid.domain
))
for exc in exceptions:
if isinstance(exc, errors.TLSFailure):
raise exc
raise errors.MultiOSError(
"failed to connect to XMPP domain {!r}".format(jid.domain),
exceptions
)
class Client:
"""
Base class to implement an XMPP client.
:param local_jid: Jabber ID to connect as
:type local_jid: :class:`~aioxmpp.JID`
:param security_layer: Configuration for authentication and TLS
:type security_layer: :class:`~aioxmpp.SecurityLayer`
:param negotiation_timeout: Timeout for the individual stream negotiation
steps (bounds initial connection time)
:type negotiation_timeout: :class:`datetime.timedelta`
:param override_peer: Connection options which take precedence over the
standardised connection options
:type override_peer: sequence of connection option triples
:param max_inital_attempts: Maximum number of initial connection attempts
:type max_initial_attempts: :class:`int`
:param loop: Override the :mod:`asyncio` event loop to use
:type loop: :class:`asyncio.BaseEventLoop` or :data:`None`
:param logger: Logger to use instead of the default logger
:type logger: :class:`logging.Logger` or :data:`None`
These classes deal with managing the :class:`~aioxmpp.stream.StanzaStream`
and the underlying :class:`~aioxmpp.protocol.XMLStream` instances. The
abstract client provides functionality for connecting the xmlstream as well
as signals which indicate changes in the stream state.
The `security_layer` is best created using the
:func:`aioxmpp.security_layer.make` function and must provide
authentication for the given `local_jid`.
If `loop` is given, it must be a :class:`asyncio.BaseEventLoop`
instance. If it is not given, the current event loop is used.
As a glue between the stanza stream and the XML stream, it also knows about
stream management and performs stream management negotiation. It is
specialized on client operations, which implies that it will try to keep
the stream alive as long as wished by the client.
The client will attempt to connect to the server(s) associated with the
`local_jid`, using the prioritised `override_peer` setting or the
standardised options for connecting (see :meth:`discover_connectors`). The
initial connection attempt must succeed within `max_initial_attempts`.
If the connection breaks after the first connection attempt, the client
will try to resume the connection transparently. If the server supports
stream management (:xep:`198`) with resumption, this is entirely
transparent to all operations over the stream. If the stream is not
resumable or the resumption fails and `allow_implicit_reconnect` is true,
the application and services using the stream are notified about that. If,
in that situation, `allow_implicit_reconnect` is false instead, the client
stops with an error.
The number of reconnection attempts is generally unbounded. The application
is notified that the stream got interrupted with the
:meth:`on_stream_suspended` is emitted. After reconnection,
:meth:`on_stream_established` is emitted (possibly preceded by a
:meth:`on_stream_destroyed` emission if the stream failed to resume). If
the application wishes to bound the time the stream tries to transparently
reconnect, it should connect to the :meth:`on_stream_suspended` signal and
stop the stream as needed.
The reconnection attempts are throttled using expenential backoff
controlled by the :attr:`backoff_start`, :attr:`backoff_factor` and
:attr:`backoff_cap` attributes.
.. note::
If `max_initial_attempts` is :data:`None`, the stream will try
indefinitly to connect to the server even if the connection has
never succeeded yet. This is may mask problems with the configuration of
the client itself, because the client cannot successfully distinguish
permanent problems arising from the configuration (of the client or the
server) from problems arising from transient problems such as network
faliures.
This may severely degrade usabilty, because the client is then stuck in
a connect loop without any usable feedback. Setting a bound for the
initial connection attempt is usually better, for interactive
applications an upper bound of 1 might make most sense (possibly the
interactive application may retry on its own if the user did not
indicate that they wish to do so after a timeout). We’ll leave the UX
considerations up to you.
.. versionchanged:: 0.4
Since 0.4, support for legacy XMPP sessions has been implemented. Mainly
for compatiblity with ejabberd.
.. versionchanged:: 0.8
The amount of initial connection attempts is now bounded by
`max_initial_attempts`. The :meth:`on_stream_suspended` signal and the
associated logic has been introduced.
Controlling the client:
.. automethod:: start
.. automethod:: stop
.. autoattribute:: running
.. attribute:: negotiation_timeout = timedelta(seconds=60)
The timeout applied to the connection process and the individual steps
of negotiating the stream. See the `negotiation_timeout` argument to
:func:`connect_xmlstream`.
.. attribute:: override_peer
A sequence of triples ``(host, port, connector)``, where `host` must be
a host name or IP as string, `port` must be a port number and
`connector` must be a :class:`aioxmpp.connector.BaseConnctor` instance.
These connection options are passed to :meth:`connect_xmlstream` and
thus take precedence over the options discovered using
:meth:`discover_connectors`.
.. note::
If Stream Management is used and the peer server provided a location
to connect to on resumption, that location is preferred even over the
options set here.
.. versionadded:: 0.6
Connection information:
.. autoattribute:: established
.. autoattribute:: local_jid
.. attribute:: stream
The :class:`~aioxmpp.stream.StanzaStream` instance used by the node.
.. attribute:: stream_features
An instance of :class:`~aioxmpp.nonza.StreamFeatures`. This is the
most-recently received stream features information (the one received
right before resource binding).
While no stream has been established yet, this is :data:`None`. During
transparent re-negotiation, that information may be obsolete. However,
when :attr:`before_stream_established` fires, the information is
up-to-date.
Configuration of exponential backoff for reconnects:
.. attribute:: backoff_start
:annotation: = timedelta(1)
When an underlying XML stream fails due to connectivity issues (generic
:class:`OSError` raised), exponential backoff takes place before
attempting to reconnect.
The initial time to wait before reconnecting is described by
:attr:`backoff_start`.
.. attribute:: backoff_factor
:annotation: = 1.2
Each subsequent time a connection fails, the previous backoff time is
multiplied with :attr:`backoff_factor`.
.. attribute:: backoff_cap
:annotation: = timedelta(60)
The backoff time is capped to :attr:`backoff_cap`, to avoid having
unrealistically high values.
Signals:
.. signal:: on_failure(err)
This signal is fired when the client fails and stops.
.. syncsignal:: before_stream_established()
This coroutine signal is executed right before
:meth:`on_stream_established` fires.
.. signal:: on_stopped()
Fires when the client stops gracefully. This is the counterpart to
:meth:`on_failure`.
.. signal:: on_stream_established()
When the stream is established and resource binding took place, this
event is fired. It means that the stream can now be used for XMPP
interactions.
.. signal:: on_stream_suspended(reason)
The stream has been suspened due to a connection failure.
:param reason: The exception which terminated the stream.
:type reason: :class:`Exception`
This signal may be immediately followed by a
:meth:`on_stream_destroyed`, if the stream did not support stream
resumption. Otherwise, a new connection is attempted transparently.
In general, this signal exists solely for informational purposes. It
can be used to drive a user interface which indicates that messages may
be delivered with delay, because the underlying network is transiently
interrupted.
:meth:`on_stream_suspended` is not emitted if the stream was stopped on
user request.
Only :meth:`on_stream_destroyed` indicates that state was actually lost
and that others most likely see or saw an unavailable presence broadcast
for the resource.
.. versionadded:: 0.8
.. signal:: on_stream_destroyed(reason=None)
This is called whenever a stream is destroyed. The conditions for this
are the same as for
:attr:`aioxmpp.stream.StanzaStream.on_stream_destroyed`.
:param reason: An optional exception which indicates the reason for the
destruction of the stream.
:type reason: :class:`Exception`
This event can be used to know when to discard all state about the XMPP
connection, such as roster information. Services implemented in
:mod:`aioxmpp` generally subscribe to this signal to discard cached
state.
`reason` is optional. It is given if there is has been a specific
exception which describes the cause for the stream destruction, such as
a :class:`ConnectionError`.
.. versionchanged:: 0.8
The `reason` argument was added.
Services:
.. automethod:: summon
Miscellaneous:
.. attribute:: logger
The :class:`logging.Logger` instance which is used by the
:class:`Client`. This is the `logger` passed to the constructor or a
logger derived from the fully qualified name of the class.
.. versionadded:: 0.6
The :attr:`logger` attribute was added.
"""
on_failure = callbacks.Signal()
on_stopped = callbacks.Signal()
on_stream_destroyed = callbacks.Signal()
on_stream_suspended = callbacks.Signal()
on_stream_established = callbacks.Signal()
before_stream_established = callbacks.SyncSignal()
def __init__(self,
local_jid,
security_layer,
*,
negotiation_timeout=timedelta(seconds=60),
max_initial_attempts=4,
override_peer=[],
loop=None,
logger=None):
super().__init__()
self._local_jid = local_jid
self._loop = loop or asyncio.get_event_loop()
self._main_task = None
self._security_layer = security_layer
self._failure_future = asyncio.Future()
self.logger = (logger or
logging.getLogger(".".join([
type(self).__module__,
type(self).__qualname__,
])))
self._backoff_time = None
self._established = False
self._is_suspended = False
# track whether the connection succeeded *at least once*
# used to enforce max_initial_attempts
self._had_connection = False
self._nattempt = 0
self._services = {}
self.stream_features = None
self.negotiation_timeout = negotiation_timeout
self.backoff_start = timedelta(seconds=1)
self.backoff_factor = 1.2
self.backoff_cap = timedelta(seconds=60)
self.override_peer = list(override_peer)
self._max_initial_attempts = max_initial_attempts
self.on_stopped.logger = self.logger.getChild("on_stopped")
self.on_failure.logger = self.logger.getChild("on_failure")
self.on_stream_established.logger = \
self.logger.getChild("on_stream_established")
self.on_stream_destroyed.logger = \
self.logger.getChild("on_stream_destroyed")
self.on_stream_suspended.logger = \
self.logger.getChild("on_stream_suspended")
self.stream = stream.StanzaStream(local_jid.bare())
def _stream_failure(self, exc):
if self._failure_future.done():
self.logger.warning(
"something is odd: failure future is already done ..."
)
return
if not self._is_suspended:
self.on_stream_suspended(exc)
self._is_suspended = True
self._failure_future.set_result(exc)
self._failure_future = asyncio.Future()
def _stream_destroyed(self, reason):
if not self._is_suspended:
if not isinstance(reason, stream.DestructionRequested):
self.on_stream_suspended(reason)
self._is_suspended = True
if self._established:
self._established = False
self.on_stream_destroyed()
def _on_main_done(self, task):
try:
task.result()
except asyncio.CancelledError:
# task terminated normally
self.on_stopped()
except Exception as err:
self.logger.exception("main failed")
self.on_failure(err)
@asyncio.coroutine
def _try_resume_stream_management(self, xmlstream, features):
try:
yield from self.stream.resume_sm(xmlstream)
except errors.StreamNegotiationFailure as exc:
self.logger.warn("failed to resume stream (%s)",
exc)
return False
return True
@asyncio.coroutine
def _negotiate_legacy_session(self):
self.logger.debug(
"remote server announces support for legacy sessions"
)
yield from self.stream.send(
stanza.IQ(type_=structs.IQType.SET,
payload=rfc3921.Session())
)
self.logger.debug(
"legacy session negotiated (upgrade your server!)"
)
@asyncio.coroutine
def _negotiate_stream(self, xmlstream, features):
server_can_do_sm = True
try:
features[nonza.StreamManagementFeature]
except KeyError:
if self.stream.sm_enabled:
self.logger.warn("server isn’t advertising SM anymore")
self.stream.stop_sm()
server_can_do_sm = False
self.logger.debug("negotiating stream (server_can_do_sm=%s)",
server_can_do_sm)
if self.stream.sm_enabled:
resumed = yield from self._try_resume_stream_management(
xmlstream, features)
if resumed:
return features, resumed
else:
resumed = False
self.stream_features = features
self.stream.start(xmlstream)
if not resumed:
self.logger.debug("binding to resource")
yield from self._bind()
if server_can_do_sm:
self.logger.debug("attempting to start stream management")
try:
yield from self.stream.start_sm()
except errors.StreamNegotiationFailure:
self.logger.debug("stream management failed to start")
self.logger.debug("stream management started")
try:
features[rfc3921.SessionFeature]
except KeyError:
pass # yay
else:
yield from self._negotiate_legacy_session()
self._established = True
yield from self.before_stream_established()
self.on_stream_established()
return features, resumed
@asyncio.coroutine
def _bind(self):
iq = stanza.IQ(type_=structs.IQType.SET)
iq.payload = rfc6120.Bind(resource=self._local_jid.resource)
try:
result = yield from self.stream.send(iq)
except errors.XMPPError as exc:
raise errors.StreamNegotiationFailure(
"Resource binding failed: {}".format(exc)
)
self._local_jid = result.jid
self.stream.local_jid = result.jid.bare()
self.logger.info("bound to jid: %s", self._local_jid)
@asyncio.coroutine
def _main_impl(self):
failure_future = self._failure_future
override_peer = []
if self.stream.sm_enabled:
sm_location = self.stream.sm_location
if sm_location:
override_peer.append((
str(sm_location[0]),
sm_location[1],
connector.STARTTLSConnector(),
))
override_peer += self.override_peer
tls_transport, xmlstream, features = \
yield from connect_xmlstream(
self._local_jid,
self._security_layer,
negotiation_timeout=self.negotiation_timeout.total_seconds(),
override_peer=override_peer,
loop=self._loop,
logger=self.logger)
self._had_connection = True
try:
features, sm_resumed = yield from self._negotiate_stream(
xmlstream,
features)
self._is_suspended = False
self._backoff_time = None
exc = yield from failure_future
self.logger.error("stream failed: %s", exc)
raise exc
except asyncio.CancelledError:
self.logger.info("client shutting down (on request)")
# cancelled, this means a clean shutdown is requested
yield from self.stream.close()
raise
finally:
self.logger.info("stopping stream")
self.stream.stop()
@asyncio.coroutine
def _main(self):
with contextlib.ExitStack() as stack:
stack.enter_context(
self.stream.on_failure.context_connect(self._stream_failure)
)
stack.enter_context(
self.stream.on_stream_destroyed.context_connect(
self._stream_destroyed)
)
while True:
self._nattempt += 1
self._failure_future = asyncio.Future()
try:
yield from self._main_impl()
except errors.StreamError as err:
if err.condition == (namespaces.streams, "conflict"):
self.logger.debug("conflict!")
raise
except (errors.StreamNegotiationFailure,
aiosasl.SASLError):
if self.stream.sm_enabled:
self.stream.stop_sm()
raise
except (OSError, dns.resolver.NoNameservers) as exc:
self.logger.info("connection error: (%s) %s",
type(exc).__qualname__,
exc)
if (not self._had_connection and
self._max_initial_attempts is not None and
self._nattempt >= self._max_initial_attempts):
self.logger.warning("out of connection attempts")
raise
if self._backoff_time is None:
self._backoff_time = self.backoff_start.total_seconds()
self.logger.debug("re-trying after %.1f seconds",
self._backoff_time)
yield from asyncio.sleep(self._backoff_time)
self._backoff_time *= self.backoff_factor
if self._backoff_time > self.backoff_cap.total_seconds():
self._backoff_time = self.backoff_cap.total_seconds()
continue # retry
def start(self):
"""
Start the client. If it is already :attr:`running`,
:class:`RuntimeError` is raised.
While the client is running, it will try to keep an XMPP connection
open to the server associated with :attr:`local_jid`.
"""
if self.running:
raise RuntimeError("client already running")
self._main_task = asyncio.async(
self._main(),
loop=self._loop
)
self._main_task.add_done_callback(self._on_main_done)
def stop(self):
"""
Stop the client. This sends a signal to the clients main task which
makes it terminate.
It may take some cycles through the event loop to stop the client
task. To check whether the task has actually stopped, query
:attr:`running`.
"""
if not self.running:
return
self.logger.debug("stopping main task of %r", self, stack_info=True)
self._main_task.cancel()
# services
def _summon(self, class_):
try:
return self._services[class_]
except KeyError:
instance = class_(
self,
logger_base=self.logger,
dependencies={
depclass: self._services[depclass]
for depclass in class_.ORDER_AFTER
}
)
self._services[class_] = instance
return instance
def summon(self, class_):
"""
Summon a :class:`~aioxmpp.service.Service` for the client.
If the `class_` has already been summoned for the client, it’s instance
is returned.
Otherwise, all requirements for the class are first summoned (if they
are not there already). Afterwards, the class itself is summoned and
the instance is returned.
"""
requirements = sorted(class_.ORDER_AFTER)
for req in requirements:
self._summon(req)
return self._summon(class_)
# properties
@property
def local_jid(self):
"""
The :class:`~aioxmpp.JID` the client currently has. While the
client is disconnected, which parts of the :attr:`local_jid` can be
relied upon depends on the authentication mechanism used. For example,
using anonymous authentication, the server dictates even the local part
of the JID and it will change after a reconnect. For more common
authentication schemes (such as normal password-based authentication),
the localpart is usually chosen by the client.
For interoperability with different authentication schemes, code must
invalidate all copies of this attribute when a
:meth:`on_stream_established` or :meth:`on_stream_destroyed` event is
emitted.
Writing this attribute is not allowed, as changing the JID introduces a
lot of issues with respect to reusability of the stream. Instanciate a
new :class:`Client` if you need to change the bare part of the JID.
.. note::
Changing the resource between reconnects may be allowed later.
"""
return self._local_jid
@property
def running(self):
"""
true if the client is currently running, false otherwise.
"""
return self._main_task is not None and not self._main_task.done()
@property
def established(self):
"""
true if the stream is currently established (as defined in
:attr:`on_stream_established`) and false otherwise.
"""
return self._established
def connected(self, *, presence=structs.PresenceState(False), **kwargs):
"""
Return a :class:`.node.UseConnected` context manager which does not
modify the presence settings.
The keyword arguments are passed to the :class:`.node.UseConnected`
context manager constructor.
.. versionadded:: 0.8
"""
return UseConnected(self, presence=presence, **kwargs)
class PresenceManagedClient(Client):
"""
Client whose connection is controlled by its configured presence.
.. seealso::
:class:`Client`
for a description of the arguments.
The presence is set using :attr:`presence` or the :class:`PresenceServer`
service. If the set presence is an *available* presence, the client is
started (if it is not already running). If the set presence is an
*unavailable* presence, the unavailable presence is broadcast and the
client is stopped.
While the start/stop interfaces of :class:`~.Client` are still available,
using them may interfere with the behaviour of the presence automagic.
The initial presence is set to `unavailable`, thus, the client will not
connect immediately.
.. autoattribute:: presence
.. automethod:: set_presence
.. automethod:: connected
Signals:
.. attribute:: on_presence_sent
The event is fired after :meth:`.Client.on_stream_established` and after
the current presence has been sent to the server as *initial presence*.
.. versionchanged:: 0.8
Since 0.8, the :class:`PresenceManagedClient` is implemented on top of
:class:`PresenceServer`. Changing the presence via the
:class:`PresenceServer` has the same effect as writing :attr:`presence`
or calling :meth:`set_presence`.
"""
on_presence_sent = callbacks.Signal()
def __init__(self, jid, security_layer, **kwargs):
super().__init__(jid, security_layer, **kwargs)
self._presence_server = self.summon(mod_presence.PresenceServer)
self._presence_server.on_presence_state_changed.connect(
self._update_presence
)
self.on_stream_established.connect(self._handle_stream_established)
def _handle_stream_established(self):
self.on_presence_sent()
def _update_presence(self):
if self._presence_server.state.available:
if not self.running:
self.start()
else:
if self.running:
self.stop()
@property
def presence(self):
"""
Control or query the current presence state (see
:class:`~.PresenceState`) of the client. Note that when
reading, the property only returns the "set" value, not the actual
value known to the server (and others). This may differ if the
connection is still being established.
.. seealso::
Setting the presence state using :attr:`presence` clears the
`status` of the presence. To set the status and state at once,
use :meth:`set_presence`.
Upon setting this attribute, the :class:`PresenceManagedClient` will do
whatever neccessary to achieve the given presence. If the presence is
an `available` presence, the client will attempt to connect to the
server. If the presence is `unavailable` and the client is currently
connected, it will disconnect.
Instead of setting the presence to unavailable, :meth:`stop` can also
be called. The :attr:`presence` attribute is *not* affected by calls to
:meth:`start` or :meth:`stop`.
"""
return self._presence_server.state
@presence.setter
def presence(self, value):
call_update = value == self.presence
self._presence_server.set_presence(value)
if call_update:
self._update_presence()
def set_presence(self, state, status):
"""
Set the presence `state` and `status` on the client. This has the same
effects as writing `state` to :attr:`presence`, but the status of the
presence is also set at the same time.
`status` must be either a string or something which can be passed to
:class:`dict`. If it is a string, the string is wrapped in a ``{None:
status}`` dictionary. Otherwise, the dictionary is set as the
:attr:`~.Presence.status` attribute of the presence stanza. It
must map :class:`aioxmpp.structs.LanguageTag` instances to strings.
The `status` is the text shown alongside the `state` (indicating
availability such as *away*, *do not disturb* and *free to chat*).
"""
self._presence_server.set_presence(state, status=status)
def connected(self, **kwargs):
"""
Return a :class:`.node.UseConnected` context manager which sets the
presence to available.
The keyword arguments are passed to the :class:`.node.UseConnected`
context manager constructor.
.. note::
In contrast to the same method on :class:`Client`, this method
implies setting an available presence.
.. versionadded:: 0.6
"""
return UseConnected(self, **kwargs)
[docs]class UseConnected:
"""
Asynchronous context manager which connects and disconnects a
:class:`.Client`.
:param client: The client to manage
:type client: :class:`.Client`
:param timeout: Limit on the time it may take to start the client
:type timeout: :class:`datetime.timedelta` or :data:`None`
:param presence: Presence state to set on the client (deprecated)
:type presence: :class:`.PresenceState`
When the asynchronous context is entered (see :pep:`492`), the client is
connected. This blocks until the client has finished connecting and the
stream is established. If the client takes longer than `timeout` to
connect, :class:`TimeoutError` is raised and the client is stopped. The
context manager returns the :attr:`~.Client.stream` of the client.
When the context is exited, the client is disconnected and the context
manager waits for the client to cleanly shut down the stream.
If the client is already connected when the context is entered, the
connection is re-used and not shut down when the context is entered, but
leaving the context still disconnects the client.
If the `presence` refers to an available presence, the
:class:`.PresenceServer` is :meth:`~.Client.summon`\ -ed on the `client`.
The presence is set using :meth:`~.PresenceServer.set_presence` (clearing
the :attr:`~.PresenceServer.status` and resetting
:attr:`~.PresenceServer.priority` to 0) before the client is connected. If
the client is already connected, the presence is set when the context is
entered.
.. deprecated:: 0.8
The use of the `presence` argument is deprecated. The deprecation will
happen in two phases:
1. Until (but not including the release of) 1.0, passing a presence
state which refers to an available presence will emit
:class:`DeprecationWarning`. This *includes* the default of the
argument, so unless an unavailable presence state is passed
explicitly, all uses of :class:`UseConnected` emit that warning.
2. Starting with 1.0, passing an available presence will raise
:class:`ValueError`.
3. Starting with a to-be-determined release after 1.0, passing the
`presence` argument at all will raise :class:`TypeError`.
Users which previously used the `presence` argument should use the
:class:`.PresenceServer` service on the client and set the presence
before using the context manager instead.
.. autoattribute:: presence
See the description of the `presence` argument.
.. deprecated:: 0.8
Using this attribute (for reading or writing) is deprecated and emits
a deprecation warning.
.. autoattribute:: timeout
See the description of the `timeout` argument.
.. deprecated:: 0.8
Using this attribute (for reading or writing) is deprecated and emits
a deprecation warning.
"""
def __init__(self, client, *,
timeout=None,
presence=structs.PresenceState(True)):
super().__init__()
self._client = client
self._timeout = timeout
self._presence = presence
if presence.available:
warnings.warn(
"using an available presence state for UseConnected is"
" deprecated and will raise ValueError as of 1.0",
DeprecationWarning,
stacklevel=1,
)
@property
def timeout(self):
warnings.warn(
"the timeout attribute is deprecated and will be removed in 1.0",
DeprecationWarning,
stacklevel=1,
)
return self._timeout
@timeout.setter
[docs] def timeout(self, value):
warnings.warn(
"the timeout attribute is deprecated and will be removed in 1.0",
DeprecationWarning,
stacklevel=1,
)
self._timeout = value
@property
def presence(self):
warnings.warn(
"the presence attribute is deprecated and will be removed in 1.0",
DeprecationWarning,
stacklevel=1,
)
return self._presence
@presence.setter
[docs] def presence(self, value):
warnings.warn(
"the presence attribute is deprecated and will be removed in 1.0",
DeprecationWarning,
stacklevel=1,
)
self._presence = value
@asyncio.coroutine
def __aenter__(self):
if self._presence.available:
svc = self._client.summon(
mod_presence.PresenceServer
)
svc.set_presence(self._presence)
if self._client.established:
return self._client.stream
conn_future = asyncio.Future()
self._client.on_stream_established.connect(
conn_future,
self._client.on_stream_established.AUTO_FUTURE,
)
self._client.on_failure.connect(
conn_future,
self._client.on_failure.AUTO_FUTURE,
)
if not self._client.running:
self._client.start()
if self._timeout is not None:
try:
yield from asyncio.wait_for(
conn_future,
self._timeout.total_seconds(),
)
except asyncio.TimeoutError:
self._client.stop()
raise TimeoutError()
else:
yield from conn_future
return self._client.stream
@asyncio.coroutine
def __aexit__(self, exc_type, exc_value, exc_traceback):
if not self._client.running:
return
disconn_future = asyncio.Future()
self._client.on_stopped.connect(
disconn_future,
self._client.on_stopped.AUTO_FUTURE,
)
self._client.on_failure.connect(
disconn_future,
self._client.on_failure.AUTO_FUTURE,
)
self._client.stop()
try:
yield from disconn_future
except Exception:
# we don’t want to re-raise that; the stream is dead, goal
# achieved.
pass