view sat/plugins/plugin_adhoc_dbus.py @ 3153:2c7b42f53e9a

core (xmpp): avoid starting several clients at the same time: a check is done to avoid running startConnection several times at once, which would lead to the creation of several SatXMPPEntity instances at the same time, resulting in many issues. If startConnection is called while a previous one is not finished yet, a CancelError is now raised.
author Goffi <goffi@goffi.org>
date Mon, 03 Feb 2020 13:46:24 +0100
parents 46a6251713d3
children be6d91572633
line wrap: on
line source

#!/usr/bin/env python3


# SAT plugin for adding D-Bus to Ad-Hoc Commands
# Copyright (C) 2009-2020 Jérôme Poisson (goffi@goffi.org)

# This program is free software: you can redistribute it and/or modify
# it under the terms of the GNU Affero 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 Affero General Public License for more details.

# You should have received a copy of the GNU Affero General Public License
# along with this program.  If not, see <http://www.gnu.org/licenses/>.

from sat.core.i18n import D_, _
from sat.core.constants import Const as C
from sat.core.log import getLogger

log = getLogger(__name__)
from twisted.internet import defer
from twisted.words.protocols.jabber import jid
from wokkel import data_form

try:
    from lxml import etree
except ImportError:
    etree = None
    log.warning("Missing module lxml, please download/install it from http://lxml.de/ ."
                "Auto D-Bus discovery will be disabled")
from collections import OrderedDict
import os.path
import uuid
try:
    import dbus
    from dbus.mainloop.glib import DBusGMainLoop
except ImportError:
    dbus = None
    log.warning("Missing module dbus, please download/install it, "
                "auto D-Bus discovery will be disabled")

else:
    DBusGMainLoop(set_as_default=True)

NS_MEDIA_PLAYER = "org.salutatoi.mediaplayer"
FD_NAME = "org.freedesktop.DBus"
FD_PATH = "/org/freedekstop/DBus"
INTROSPECT_IFACE = "org.freedesktop.DBus.Introspectable"
MPRIS_PREFIX = "org.mpris.MediaPlayer2"
CMD_GO_BACK = "GoBack"
CMD_GO_FWD = "GoFW"
SEEK_OFFSET = 5 * 1000 * 1000
MPRIS_COMMANDS = ["org.mpris.MediaPlayer2.Player." + cmd for cmd in (
    "Previous", CMD_GO_BACK, "PlayPause", CMD_GO_FWD, "Next")]
MPRIS_PATH = "/org/mpris/MediaPlayer2"
MPRIS_PROPERTIES = OrderedDict((
    ("org.mpris.MediaPlayer2", (
        "Identity",
        )),
    ("org.mpris.MediaPlayer2.Player", (
        "Metadata",
        "PlaybackStatus",
        "Volume",
        )),
    ))
MPRIS_METADATA_KEY = "Metadata"
MPRIS_METADATA_MAP = OrderedDict((
    ("xesam:title", "Title"),
    ))

INTROSPECT_METHOD = "Introspect"
IGNORED_IFACES_START = (
    "org.freedesktop",
    "org.qtproject",
    "org.kde.KMainWindow",
)  # commands in interface starting with these values will be ignored
FLAG_LOOP = "LOOP"

PLUGIN_INFO = {
    C.PI_NAME: "Ad-Hoc Commands - D-Bus",
    C.PI_IMPORT_NAME: "AD_HOC_DBUS",
    C.PI_TYPE: "Misc",
    C.PI_PROTOCOLS: [],
    C.PI_DEPENDENCIES: ["XEP-0050"],
    C.PI_MAIN: "AdHocDBus",
    C.PI_HANDLER: "no",
    C.PI_DESCRIPTION: _("""Add D-Bus management to Ad-Hoc commands"""),
}


class AdHocDBus(object):

    def __init__(self, host):
        log.info(_("plugin Ad-Hoc D-Bus initialization"))
        self.host = host
        if etree is not None:
            host.bridge.addMethod(
                "adHocDBusAddAuto",
                ".plugin",
                in_sign="sasasasasasass",
                out_sign="(sa(sss))",
                method=self._adHocDBusAddAuto,
                async_=True,
            )
        host.bridge.addMethod(
            "adHocRemotesGet",
            ".plugin",
            in_sign="s",
            out_sign="a(sss)",
            method=self._adHocRemotesGet,
            async_=True,
        )
        self._c = host.plugins["XEP-0050"]
        host.registerNamespace("mediaplayer", NS_MEDIA_PLAYER)
        if dbus is not None:
            self.session_bus = dbus.SessionBus()
            self.fd_object = self.session_bus.get_object(
                FD_NAME, FD_PATH, introspect=False)

    def profileConnected(self, client):
        if dbus is not None:
            self._c.addAdHocCommand(
                client, self.localMediaCb, D_("Media Players"),
                node=NS_MEDIA_PLAYER,
                timeout=60*60*6  # 6 hours timeout, to avoid breaking remote
                                 # in the middle of a movie
            )

    def _DBusAsyncCall(self, proxy, method, *args, **kwargs):
        """ Call a DBus method asynchronously and return a deferred

        @param proxy: DBus object proxy, as returner by get_object
        @param method: name of the method to call
        @param args: will be transmitted to the method
        @param kwargs: will be transmetted to the method, except for the following poped
                       values:
                       - interface: name of the interface to use
        @return: a deferred

        """
        d = defer.Deferred()
        interface = kwargs.pop("interface", None)
        kwargs["reply_handler"] = lambda ret=None: d.callback(ret)
        kwargs["error_handler"] = d.errback
        proxy.get_dbus_method(method, dbus_interface=interface)(*args, **kwargs)
        return d

    def _DBusGetProperty(self, proxy, interface, name):
        return self._DBusAsyncCall(
            proxy, "Get", interface, name, interface="org.freedesktop.DBus.Properties")


    def _DBusListNames(self):
        return self._DBusAsyncCall(self.fd_object, "ListNames")

    def _DBusIntrospect(self, proxy):
        return self._DBusAsyncCall(proxy, INTROSPECT_METHOD, interface=INTROSPECT_IFACE)

    def _acceptMethod(self, method):
        """ Return True if we accept the method for a command
        @param method: etree.Element
        @return: True if the method is acceptable

        """
        if method.xpath(
            "arg[@direction='in']"
        ):  # we don't accept method with argument for the moment
            return False
        return True

    @defer.inlineCallbacks
    def _introspect(self, methods, bus_name, proxy):
        log.debug("introspecting path [%s]" % proxy.object_path)
        introspect_xml = yield self._DBusIntrospect(proxy)
        el = etree.fromstring(introspect_xml)
        for node in el.iterchildren("node", "interface"):
            if node.tag == "node":
                new_path = os.path.join(proxy.object_path, node.get("name"))
                new_proxy = self.session_bus.get_object(
                    bus_name, new_path, introspect=False
                )
                yield self._introspect(methods, bus_name, new_proxy)
            elif node.tag == "interface":
                name = node.get("name")
                if any(name.startswith(ignored) for ignored in IGNORED_IFACES_START):
                    log.debug("interface [%s] is ignored" % name)
                    continue
                log.debug("introspecting interface [%s]" % name)
                for method in node.iterchildren("method"):
                    if self._acceptMethod(method):
                        method_name = method.get("name")
                        log.debug("method accepted: [%s]" % method_name)
                        methods.add((proxy.object_path, name, method_name))

    def _adHocDBusAddAuto(self, prog_name, allowed_jids, allowed_groups, allowed_magics,
                          forbidden_jids, forbidden_groups, flags, profile_key):
        client = self.host.getClient(profile_key)
        return self.adHocDBusAddAuto(
            client, prog_name, allowed_jids, allowed_groups, allowed_magics,
            forbidden_jids, forbidden_groups, flags)

    @defer.inlineCallbacks
    def adHocDBusAddAuto(self, client, prog_name, allowed_jids=None, allowed_groups=None,
                         allowed_magics=None, forbidden_jids=None, forbidden_groups=None,
                         flags=None):
        bus_names = yield self._DBusListNames()
        bus_names = [bus_name for bus_name in bus_names if "." + prog_name in bus_name]
        if not bus_names:
            log.info("Can't find any bus for [%s]" % prog_name)
            defer.returnValue(("", []))
        bus_names.sort()
        for bus_name in bus_names:
            if bus_name.endswith(prog_name):
                break
        log.info("bus name found: [%s]" % bus_name)
        proxy = self.session_bus.get_object(bus_name, "/", introspect=False)
        methods = set()

        yield self._introspect(methods, bus_name, proxy)

        if methods:
            self._addCommand(
                client,
                prog_name,
                bus_name,
                methods,
                allowed_jids=allowed_jids,
                allowed_groups=allowed_groups,
                allowed_magics=allowed_magics,
                forbidden_jids=forbidden_jids,
                forbidden_groups=forbidden_groups,
                flags=flags,
            )

        defer.returnValue((str(bus_name), methods))

    def _addCommand(self, client, adhoc_name, bus_name, methods, allowed_jids=None,
                    allowed_groups=None, allowed_magics=None, forbidden_jids=None,
                    forbidden_groups=None, flags=None):
        if flags is None:
            flags = set()

        def DBusCallback(client, command_elt, session_data, action, node):
            actions = session_data.setdefault("actions", [])
            names_map = session_data.setdefault("names_map", {})
            actions.append(action)

            if len(actions) == 1:
                # it's our first request, we ask the desired new status
                status = self._c.STATUS.EXECUTING
                form = data_form.Form("form", title=_("Command selection"))
                options = []
                for path, iface, command in methods:
                    label = command.rsplit(".", 1)[-1]
                    name = str(uuid.uuid4())
                    names_map[name] = (path, iface, command)
                    options.append(data_form.Option(name, label))

                field = data_form.Field(
                    "list-single", "command", options=options, required=True
                )
                form.addField(field)

                payload = form.toElement()
                note = None

            elif len(actions) == 2:
                # we should have the answer here
                try:
                    x_elt = next(command_elt.elements(data_form.NS_X_DATA, "x"))
                    answer_form = data_form.Form.fromElement(x_elt)
                    command = answer_form["command"]
                except (KeyError, StopIteration):
                    raise self._c.AdHocError(self._c.ERROR.BAD_PAYLOAD)

                if command not in names_map:
                    raise self._c.AdHocError(self._c.ERROR.BAD_PAYLOAD)

                path, iface, command = names_map[command]
                proxy = self.session_bus.get_object(bus_name, path)

                self._DBusAsyncCall(proxy, command, interface=iface)

                # job done, we can end the session, except if we have FLAG_LOOP
                if FLAG_LOOP in flags:
                    # We have a loop, so we clear everything and we execute again the
                    # command as we had a first call (command_elt is not used, so None
                    # is OK)
                    del actions[:]
                    names_map.clear()
                    return DBusCallback(
                        client, None, session_data, self._c.ACTION.EXECUTE, node
                    )
                form = data_form.Form("form", title=_("Updated"))
                form.addField(data_form.Field("fixed", "Command sent"))
                status = self._c.STATUS.COMPLETED
                payload = None
                note = (self._c.NOTE.INFO, _("Command sent"))
            else:
                raise self._c.AdHocError(self._c.ERROR.INTERNAL)

            return (payload, status, None, note)

        self._c.addAdHocCommand(
            client,
            DBusCallback,
            adhoc_name,
            allowed_jids=allowed_jids,
            allowed_groups=allowed_groups,
            allowed_magics=allowed_magics,
            forbidden_jids=forbidden_jids,
            forbidden_groups=forbidden_groups,
        )

    ## Local media ##

    def _adHocRemotesGet(self, profile):
        return self.adHocRemotesGet(self.host.getClient(profile))

    @defer.inlineCallbacks
    def adHocRemotesGet(self, client):
        """Retrieve available remote media controlers in our devices
        @return (list[tuple[unicode, unicode, unicode]]): list of devices with:
            - entity full jid
            - device name
            - device label
        """
        found_data = yield defer.ensureDeferred(self.host.findByFeatures(
            client, [self.host.ns_map['commands']], service=False, roster=False,
            own_jid=True, local_device=True))

        remotes = []

        for found in found_data:
            for device_jid_s in found:
                device_jid = jid.JID(device_jid_s)
                cmd_list = yield self._c.list(client, device_jid)
                for cmd in cmd_list:
                    if cmd.nodeIdentifier == NS_MEDIA_PLAYER:
                        try:
                            result_elt = yield self._c.do(client, device_jid,
                                                          NS_MEDIA_PLAYER, timeout=5)
                            command_elt = self._c.getCommandElt(result_elt)
                            form = data_form.findForm(command_elt, NS_MEDIA_PLAYER)
                            if form is None:
                                continue
                            mp_options = form.fields['media_player'].options
                            session_id = command_elt.getAttribute('sessionid')
                            if mp_options and session_id:
                                # we just want to discover player, so we cancel the
                                # session
                                self._c.do(client, device_jid, NS_MEDIA_PLAYER,
                                           action=self._c.ACTION.CANCEL,
                                           session_id=session_id)

                            for opt in mp_options:
                                remotes.append((device_jid_s,
                                                opt.value,
                                                opt.label or opt.value))
                        except Exception as e:
                            log.warning(_(
                                "Can't retrieve remote controllers on {device_jid}: "
                                "{reason}".format(device_jid=device_jid, reason=e)))
                        break
        defer.returnValue(remotes)

    def doMPRISCommand(self, proxy, command):
        iface, command = command.rsplit(".", 1)
        if command == CMD_GO_BACK:
            command = 'Seek'
            args = [-SEEK_OFFSET]
        elif command == CMD_GO_FWD:
            command = 'Seek'
            args = [SEEK_OFFSET]
        else:
            args = []
        return self._DBusAsyncCall(proxy, command, *args, interface=iface)

    def addMPRISMetadata(self, form, metadata):
        """Serialise MRPIS Metadata according to MPRIS_METADATA_MAP"""
        for mpris_key, name in MPRIS_METADATA_MAP.items():
            if mpris_key in metadata:
                value = str(metadata[mpris_key])
                form.addField(data_form.Field(fieldType="fixed",
                                              var=name,
                                              value=value))

    @defer.inlineCallbacks
    def localMediaCb(self, client, command_elt, session_data, action, node):
        try:
            x_elt = next(command_elt.elements(data_form.NS_X_DATA, "x"))
            command_form = data_form.Form.fromElement(x_elt)
        except StopIteration:
            command_form = None

        if command_form is None or len(command_form.fields) == 0:
            # root request, we looks for media players
            bus_names = yield self._DBusListNames()
            bus_names = [b for b in bus_names if b.startswith(MPRIS_PREFIX)]
            if len(bus_names) == 0:
                note = (self._c.NOTE.INFO, D_("No media player found."))
                defer.returnValue((None, self._c.STATUS.COMPLETED, None, note))
            options = []
            status = self._c.STATUS.EXECUTING
            form = data_form.Form("form", title=D_("Media Player Selection"),
                                  formNamespace=NS_MEDIA_PLAYER)
            for bus in bus_names:
                player_name = bus[len(MPRIS_PREFIX)+1:]
                if not player_name:
                    log.warning(_("Ignoring MPRIS bus without suffix"))
                    continue
                options.append(data_form.Option(bus, player_name))
            field = data_form.Field(
                "list-single", "media_player", options=options, required=True
            )
            form.addField(field)
            payload = form.toElement()
            defer.returnValue((payload, status, None, None))
        else:
            # player request
            try:
                bus_name = command_form["media_player"]
            except KeyError:
                raise ValueError(_("missing media_player value"))

            if not bus_name.startswith(MPRIS_PREFIX):
                log.warning(_("Media player ad-hoc command trying to use non MPRIS bus. "
                              "Hack attempt? Refused bus: {bus_name}").format(
                              bus_name=bus_name))
                note = (self._c.NOTE.ERROR, D_("Invalid player name."))
                defer.returnValue((None, self._c.STATUS.COMPLETED, None, note))

            try:
                proxy = self.session_bus.get_object(bus_name, MPRIS_PATH)
            except dbus.exceptions.DBusException as e:
                log.warning(_("Can't get D-Bus proxy: {reason}").format(reason=e))
                note = (self._c.NOTE.ERROR, D_("Media player is not available anymore"))
                defer.returnValue((None, self._c.STATUS.COMPLETED, None, note))
            try:
                command = command_form["command"]
            except KeyError:
                pass
            else:
                yield self.doMPRISCommand(proxy, command)

            # we construct the remote control form
            form = data_form.Form("form", title=D_("Media Player Selection"))
            form.addField(data_form.Field(fieldType="hidden",
                                          var="media_player",
                                          value=bus_name))
            for iface, properties_names in MPRIS_PROPERTIES.items():
                for name in properties_names:
                    try:
                        value = yield self._DBusGetProperty(proxy, iface, name)
                    except Exception as e:
                        log.warning(_("Can't retrieve attribute {name}: {reason}")
                                    .format(name=name, reason=e))
                        continue
                    if name == MPRIS_METADATA_KEY:
                        self.addMPRISMetadata(form, value)
                    else:
                        form.addField(data_form.Field(fieldType="fixed",
                                                      var=name,
                                                      value=str(value)))

            commands = [data_form.Option(c, c.rsplit(".", 1)[1]) for c in MPRIS_COMMANDS]
            form.addField(data_form.Field(fieldType="list-single",
                                          var="command",
                                          options=commands,
                                          required=True))

            payload = form.toElement()
            status = self._c.STATUS.EXECUTING
            defer.returnValue((payload, status, None, None))