view sat/bridge/bridge_constructor/constructors/dbus/constructor.py @ 3998:402d31527af4

plugin app manager: `start` doesn't wait anymore for actual app start: Application may be long to start (e.g. a Docker app may have to download images first, and even without the downloading, the starting could be long), which may lead to UI blocking or bridge time out. To prevent that, `start` is now returning immediately, and 2 new signals are used to indicate when the application is started, of if something wrong happened. `start` now returns initial app data, including exposed data without the computed exposed data. The computed data must be retrieved after the app has been started.
author Goffi <goffi@goffi.org>
date Sat, 04 Mar 2023 18:30:47 +0100
parents 60d3861e5996
children 524856bd7b19
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#!/usr/bin/env python3


# Libervia: an XMPP client
# Copyright (C) 2009-2021 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.bridge.bridge_constructor import base_constructor


class DbusConstructor(base_constructor.Constructor):
    NAME = "dbus"
    CORE_TEMPLATE = "dbus_core_template.py"
    CORE_DEST = "dbus_bridge.py"
    CORE_FORMATS = {
        "methods_declarations": """\
        Method('{name}', arguments='{sig_in}', returns='{sig_out}'),""",

        "methods": """\
    def dbus_{name}(self, {args}):
        {debug}return self._callback("{name}", {args_no_default})\n""",

        "signals_declarations": """\
        Signal('{name}', '{sig_in}'),""",

        "signals": """\
    def {name}(self, {args}):
        self._obj.emitSignal("{name}", {args})\n""",
    }

    FRONTEND_TEMPLATE = "dbus_frontend_template.py"
    FRONTEND_DEST = CORE_DEST
    FRONTEND_FORMATS = {
        "methods": """\
    def {name}(self, {args}{async_comma}{async_args}):
        {error_handler}{blocking_call}{debug}return {result}\n""",
        "async_methods": """\
    def {name}(self{async_comma}{args}):
        loop = asyncio.get_running_loop()
        fut = loop.create_future()
        reply_handler = lambda ret=None: loop.call_soon_threadsafe(fut.set_result, ret)
        error_handler = lambda err: loop.call_soon_threadsafe(fut.set_exception, dbus_to_bridge_exception(err))
        self.db_{category}_iface.{name}({args_result}{async_comma}timeout=const_TIMEOUT, reply_handler=reply_handler, error_handler=error_handler)
        {debug}return fut\n""",
    }

    def core_completion_signal(self, completion, function, default, arg_doc, async_):
        completion["category"] = completion["category"].upper()
        completion["body"] = (
            "pass"
            if not self.args.debug
            else 'log.debug ("{}")'.format(completion["name"])
        )

    def core_completion_method(self, completion, function, default, arg_doc, async_):
        completion.update(
            {
                "debug": (
                    "" if not self.args.debug
                    else f'log.debug ("{completion["name"]}")\n{8 * " "}'
                )
            }
        )

    def frontend_completion_method(self, completion, function, default, arg_doc, async_):
        completion.update(
            {
                # XXX: we can manage blocking call in the same way as async one: if callback is None the call will be blocking
                "debug": ""
                if not self.args.debug
                else 'log.debug ("%s")\n%s' % (completion["name"], 8 * " "),
                "args_result": self.getArguments(function["sig_in"], name=arg_doc),
                "async_args": "callback=None, errback=None",
                "async_comma": ", " if function["sig_in"] else "",
                "error_handler": """if callback is None:
            error_handler = None
        else:
            if errback is None:
                errback = log.error
            error_handler = lambda err:errback(dbus_to_bridge_exception(err))
        """,
            }
        )
        if async_:
            completion["blocking_call"] = ""
            completion[
                "async_args_result"
            ] = "timeout=const_TIMEOUT, reply_handler=callback, error_handler=error_handler"
        else:
            # XXX: To have a blocking call, we must have not reply_handler, so we test if callback exists, and add reply_handler only in this case
            completion[
                "blocking_call"
            ] = """kwargs={}
        if callback is not None:
            kwargs['timeout'] = const_TIMEOUT
            kwargs['reply_handler'] = callback
            kwargs['error_handler'] = error_handler
        """
            completion["async_args_result"] = "**kwargs"
        result = (
            "self.db_%(category)s_iface.%(name)s(%(args_result)s%(async_comma)s%(async_args_result)s)"
            % completion
        )
        completion["result"] = (
            "str(%s)" if self.args.unicode and function["sig_out"] == "s" else "%s"
        ) % result