from __future__ import annotations
import argparse
import collections
import contextlib
import logging
import os
import pathlib
import signal
import sys
from typing import TYPE_CHECKING
import pykka
from pykka.messages import ProxyCall
from mopidy import config as config_lib
from mopidy import exceptions
from mopidy.audio import Audio
from mopidy.core import Core
from mopidy.internal import deps, process, timer, versioning
from mopidy.internal.gi import GLib
if TYPE_CHECKING:
from typing import Optional
logger = logging.getLogger(__name__)
_default_config = [
(pathlib.Path(base) / "mopidy" / "mopidy.conf").resolve()
for base in GLib.get_system_config_dirs() + [GLib.get_user_config_dir()]
]
DEFAULT_CONFIG = ":".join(map(str, _default_config))
def config_files_type(value):
return value.split(":")
def config_override_type(value):
try:
section, remainder = value.split("/", 1)
key, value = remainder.split("=", 1)
return (section.strip(), key.strip(), value.strip())
except ValueError:
raise argparse.ArgumentTypeError(
f"{value} must have the format section/key=value"
)
class _ParserError(Exception):
def __init__(self, message):
self.message = message
class _HelpError(Exception):
pass
class _ArgumentParser(argparse.ArgumentParser):
def error(self, message):
raise _ParserError(message)
class _HelpAction(argparse.Action):
def __init__(self, option_strings, dest=None, help=None):
super().__init__(
option_strings=option_strings,
dest=dest or argparse.SUPPRESS,
default=argparse.SUPPRESS,
nargs=0,
help=help,
)
def __call__(self, parser, namespace, values, option_string=None):
raise _HelpError()
[docs]
class Command:
"""Command parser and runner for building trees of commands.
This class provides a wraper around :class:`argparse.ArgumentParser`
for handling this type of command line application in a better way than
argprases own sub-parser handling.
"""
help: Optional[str] = None
#: Help text to display in help output.
def __init__(self):
self._children = collections.OrderedDict()
self._arguments = []
self._overrides = {}
def _build(self):
actions = []
parser = _ArgumentParser(add_help=False)
parser.register("action", "help", _HelpAction)
for args, kwargs in self._arguments:
actions.append(parser.add_argument(*args, **kwargs))
parser.add_argument(
"_args", nargs=argparse.REMAINDER, help=argparse.SUPPRESS
)
return parser, actions
[docs]
def add_child(self, name, command):
"""Add a child parser to consider using.
:param name: name to use for the sub-command that is being added.
:type name: string
"""
self._children[name] = command
[docs]
def add_argument(self, *args, **kwargs):
"""Add an argument to the parser.
This method takes all the same arguments as the
:class:`argparse.ArgumentParser` version of this method.
"""
self._arguments.append((args, kwargs))
[docs]
def set(self, **kwargs):
"""Override a value in the finaly result of parsing."""
self._overrides.update(kwargs)
[docs]
def exit(self, status_code=0, message=None, usage=None):
"""Optionally print a message and exit."""
print("\n\n".join(m for m in (usage, message) if m))
sys.exit(status_code)
def _usage(self, actions, prog):
formatter = argparse.HelpFormatter(prog)
formatter.add_usage(None, actions, [])
return formatter.format_help().strip()
def _subhelp(self, name, result):
actions = self._build()[1]
if self.help or actions:
formatter = argparse.HelpFormatter(name)
formatter.add_usage(None, actions, [], "")
formatter.start_section(None)
formatter.add_text(self.help)
formatter.start_section(None)
formatter.add_arguments(actions)
formatter.end_section()
formatter.end_section()
result.append(formatter.format_help())
for childname, child in self._children.items():
child._subhelp(" ".join((name, childname)), result)
[docs]
def parse(self, args, prog=None):
"""Parse command line arguments.
Will recursively parse commands until a final parser is found or an
error occurs. In the case of errors we will print a message and exit.
Otherwise, any overrides are applied and the current parser stored
in the command attribute of the return value.
:param args: list of arguments to parse
:type args: list of strings
:param prog: name to use for program
:type prog: string
:rtype: :class:`argparse.Namespace`
"""
prog = prog or os.path.basename(sys.argv[0])
try:
return self._parse(
args, argparse.Namespace(), self._overrides.copy(), prog
)
except _HelpError:
self.exit(0, self.format_help(prog))
def _parse(self, args, namespace, overrides, prog):
overrides.update(self._overrides)
parser, actions = self._build()
try:
result = parser.parse_args(args, namespace)
except _ParserError as exc:
self.exit(1, str(exc), self._usage(actions, prog))
if not result._args:
for attr, value in overrides.items():
setattr(result, attr, value)
delattr(result, "_args")
result.command = self
return result
child = result._args.pop(0)
if child not in self._children:
usage = self._usage(actions, prog)
self.exit(1, f"unrecognized command: {child}", usage)
return self._children[child]._parse(
result._args, result, overrides, " ".join([prog, child])
)
[docs]
def run(self, *args, **kwargs):
"""Run the command.
Must be implemented by sub-classes that are not simply an intermediate
in the command namespace.
"""
raise NotImplementedError
@contextlib.contextmanager
def _actor_error_handling(name):
try:
yield
except exceptions.BackendError as exc:
logger.error("Backend (%s) initialization error: %s", name, exc)
except exceptions.FrontendError as exc:
logger.error("Frontend (%s) initialization error: %s", name, exc)
except exceptions.MixerError as exc:
logger.error("Mixer (%s) initialization error: %s", name, exc)
except Exception:
logger.exception("Got un-handled exception from %s", name)
# TODO: move out of this utility class
[docs]
class RootCommand(Command):
def __init__(self):
super().__init__()
self.set(base_verbosity_level=0)
self.add_argument(
"-h", "--help", action="help", help="Show this message and exit"
)
self.add_argument(
"--version",
action="version",
version=f"Mopidy {versioning.get_version()}",
)
self.add_argument(
"-q",
"--quiet",
action="store_const",
const=-1,
dest="verbosity_level",
help="less output (warning level)",
)
self.add_argument(
"-v",
"--verbose",
action="count",
dest="verbosity_level",
default=0,
help="more output (repeat up to 4 times for even more)",
)
self.add_argument(
"--config",
action="store",
dest="config_files",
type=config_files_type,
default=DEFAULT_CONFIG,
metavar="FILES",
help="config files to use, colon seperated, later files override",
)
self.add_argument(
"-o",
"--option",
action="append",
dest="config_overrides",
type=config_override_type,
metavar="OPTIONS",
help="`section/key=value` values to override config options",
)
[docs]
def run(self, args, config):
def on_sigterm(loop):
logger.info("GLib mainloop got SIGTERM. Exiting...")
loop.quit()
loop = GLib.MainLoop()
GLib.unix_signal_add(
GLib.PRIORITY_DEFAULT, signal.SIGTERM, on_sigterm, loop
)
mixer_class = self.get_mixer_class(config, args.registry["mixer"])
backend_classes = args.registry["backend"]
frontend_classes = args.registry["frontend"]
core = None
exit_status_code = 0
try:
mixer = None
if mixer_class is not None:
mixer = self.start_mixer(config, mixer_class)
if mixer:
self.configure_mixer(config, mixer)
audio = self.start_audio(config, mixer)
backends = self.start_backends(config, backend_classes, audio)
core = self.start_core(config, mixer, backends, audio)
self.start_frontends(config, frontend_classes, core)
logger.info("Starting GLib mainloop")
loop.run()
except (
exceptions.BackendError,
exceptions.FrontendError,
exceptions.MixerError,
):
logger.info("Initialization error. Exiting...")
exit_status_code = 1
except KeyboardInterrupt:
logger.info("Interrupted. Exiting...")
except Exception:
logger.exception("Uncaught exception")
finally:
loop.quit()
self.stop_frontends(frontend_classes)
self.stop_core(core)
self.stop_backends(backend_classes)
self.stop_audio()
if mixer_class is not None:
self.stop_mixer(mixer_class)
process.stop_remaining_actors()
return exit_status_code
def get_mixer_class(self, config, mixer_classes):
logger.debug(
"Available Mopidy mixers: %s",
", ".join(m.__name__ for m in mixer_classes) or "none",
)
if config["audio"]["mixer"] == "none":
logger.debug("Mixer disabled")
return None
selected_mixers = [
m for m in mixer_classes if m.name == config["audio"]["mixer"]
]
if len(selected_mixers) != 1:
logger.error(
'Did not find unique mixer "%s". Alternatives are: %s',
config["audio"]["mixer"],
", ".join(m.name for m in mixer_classes) + ", none" or "none",
)
process.exit_process()
return selected_mixers[0]
def start_mixer(self, config, mixer_class):
logger.info("Starting Mopidy mixer: %s", mixer_class.__name__)
with _actor_error_handling(mixer_class.__name__):
mixer = mixer_class.start(config=config).proxy()
try:
mixer.ping().get()
return mixer
except pykka.ActorDeadError as exc:
logger.error("Actor died: %s", exc)
return None
def configure_mixer(self, config, mixer):
volume = config["audio"]["mixer_volume"]
if volume is not None:
mixer.set_volume(volume)
logger.info("Mixer volume set to %d", volume)
else:
logger.debug("Mixer volume left unchanged")
def start_audio(self, config, mixer):
logger.info("Starting Mopidy audio")
return Audio.start(config=config, mixer=mixer).proxy()
def start_backends(self, config, backend_classes, audio):
logger.info(
"Starting Mopidy backends: %s",
", ".join(b.__name__ for b in backend_classes) or "none",
)
backends = []
for backend_class in backend_classes:
with _actor_error_handling(backend_class.__name__):
with timer.time_logger(backend_class.__name__):
backend = backend_class.start(
config=config, audio=audio
).proxy()
backends.append(backend)
# Block until all on_starts have finished, letting them run in parallel
for backend in backends[:]:
try:
backend.ping().get()
except pykka.ActorDeadError as exc:
backends.remove(backend)
logger.error("Actor died: %s", exc)
return backends
def start_core(self, config, mixer, backends, audio):
logger.info("Starting Mopidy core")
core = Core.start(
config=config, mixer=mixer, backends=backends, audio=audio
).proxy()
call = ProxyCall(attr_path=["_setup"], args=[], kwargs={})
core.actor_ref.ask(call, block=True)
return core
def start_frontends(self, config, frontend_classes, core):
logger.info(
"Starting Mopidy frontends: %s",
", ".join(f.__name__ for f in frontend_classes) or "none",
)
for frontend_class in frontend_classes:
with _actor_error_handling(frontend_class.__name__):
with timer.time_logger(frontend_class.__name__):
frontend_class.start(config=config, core=core)
def stop_frontends(self, frontend_classes):
logger.info("Stopping Mopidy frontends")
for frontend_class in frontend_classes:
process.stop_actors_by_class(frontend_class)
def stop_core(self, core):
logger.info("Stopping Mopidy core")
if core:
call = ProxyCall(attr_path=["_teardown"], args=[], kwargs={})
core.actor_ref.ask(call, block=True)
process.stop_actors_by_class(Core)
def stop_backends(self, backend_classes):
logger.info("Stopping Mopidy backends")
for backend_class in backend_classes:
process.stop_actors_by_class(backend_class)
def stop_audio(self):
logger.info("Stopping Mopidy audio")
process.stop_actors_by_class(Audio)
def stop_mixer(self, mixer_class):
logger.info("Stopping Mopidy mixer")
process.stop_actors_by_class(mixer_class)
[docs]
class ConfigCommand(Command):
help = "Show currently active configuration."
def __init__(self):
super().__init__()
self.set(base_verbosity_level=-1)
[docs]
def run(self, config, errors, schemas):
data = config_lib.format(config, schemas, errors)
# Throw away all bytes that are not valid UTF-8 before printing
data = data.encode(errors="surrogateescape").decode(errors="replace")
print(data)
return 0
[docs]
class DepsCommand(Command):
help = "Show dependencies and debug information."
def __init__(self):
super().__init__()
self.set(base_verbosity_level=-1)
[docs]
def run(self):
print(deps.format_dependency_list())
return 0