def start_server(self) -> bool:
with DBus(user_mode=True) as bus, \
Unit(self.__config.get_system_service_unit_name(), \
bus=bus, _autoload=True) as service:
try:
service.Unit.Start(b"replace")
except Exception as e:
print(f"Can't start server: {e}")
return False
# print(f'Server\'s state: {service.Unit.ActiveState}')
return True
print('Can\t read server state via Dbus!')
return False
def bus_context(self):
close_bus_at_end = self._bus is None
try:
if self._bus is None:
bus = DBus()
bus.open()
else:
bus = self._bus
yield bus
finally:
if close_bus_at_end:
bus.close()
def monitor(name):
unit = Unit(name)
with DBus() as bus:
bus.match_signal(
unit.destination,
unit.path,
b"org.freedesktop.DBus.Properties",
b"PropertiesChanged",
process, # callback for this message
STATE, # maybe pass custom python objects as userdata?
)
fd = bus.get_fd()
while not STATE.EXIT:
select.select([fd], [], []) # wait for message
bus.process() # execute all methods (driver)
def _unit_action_sync(self, action, wait, timeout):
unit = self._get_systemd_unit()
job = getattr(unit.Unit, action)(b"replace")
if wait:
with DBus() as bus:
done = False
def callback(msg, error=None, userdata=None):
nonlocal done
msg.process_reply(True)
if msg.body[1] == job:
done = True
bus.match_signal(
b"org.freedesktop.systemd1",
b"/org/freedesktop/systemd1",
b"org.freedesktop.systemd1.Manager",
b"JobRemoved",
callback,
None,
)
job_object = Job(job, bus)
try:
job_object.load()
except DBusUnknownObjectError:
# Job has already completed
return
fd = bus.get_fd()
while True:
fds = select.select([fd], [], [], timeout)
if not any(fds):
break
bus.process()
if done:
break
def monitor():
with DBus() as bus:
bus.match_signal(
b"org.freedesktop.systemd1",
None,
b"org.freedesktop.DBus.Properties",
b"PropertiesChanged",
process, # callback for this message
None,
)
fd = bus.get_fd()
while True:
try:
select.select([fd], [], []) # wait for message
bus.process() # execute all methods (driver)
except KeyboardInterrupt:
break
def monitor(*args):
"""
This is a simple mock of the monitor function inside busctl. the c version can
be found in https://github.com/systemd/systemd/blob/master/src/busctl/busctl.c#L1081
a couple of interesting stuff here:
1.- We interface directly with dbus, as we need to keep it open.
2.- we construct argument for `BecomeMonitor`.
3.- we dump stuff to stdout as simple as possible.
"""
with DBus() as bus:
cargs = apply_signature(
b"asu", # signature
[
chain(*[[b"sender='%s'" %
arg, b"destination='%s'" % arg] for arg in args]),
0,
],
)
# BecomeMonitor takes 2 argument an array of string (filters) and a
# uint32 flag. We could have known this by inspecting
# /org/freedesktop/DBus object.
bus.call_method(
b"org.freedesktop.DBus",
b"/org/freedesktop/DBus",
b"org.freedesktop.DBus.Monitoring",
b"BecomeMonitor",
cargs,
)
name = bus.get_unique_name()
while True:
msg = bus.process()
if not msg.is_signal(b"org.freedesktop.DBus", b"NameLost"):
continue
msg.process_reply(False)
if msg.body == name:
break
while True:
msg = bus.process()
if msg.is_empty():
bus.wait(1000000000)
continue
msg.process_reply(True)
# print headers
pprint({k: v for k, v in msg.headers.items() if v is not None})
# print response
pprint(msg.body)
print("#*" * 40)
if msg.is_signal(b"org.freedesktop.DBus.Local", b"Disconnected"):
break
bus.wait(1000000000)
def bus_factory():
if machine:
return DBusMachine(x2char_star(machine))
else:
return DBus(user_mode=user_mode)
def bus_factory():
if machine:
return DBusMachine(machine)
else:
return DBus(user_mode=user_mode)
from app import app, db
from app.models import Image
from app.schemas import ImageSchema
from app.camera import Camera
CORS(app)
dbus = None
yolo_unit = None
camera = None
yolo_version = app.config['YOLO_VERSION']
if app.config['JETSON_PLATFORM'] == 'True':
from pystemd.systemd1 import Unit
from pystemd.dbuslib import DBus
dbus = DBus(user_mode=True)
dbus.open()
yolo_unit = Unit(b'orninet-yolov5.service', bus=dbus, _autoload=True)
# yolo_unit = Unit(bytes(f'orninet-yolov{yolo_version}.service', 'utf-8'), bus=dbus, _autoload=True)
else:
class PlaceholderUnit(object):
def __init__(self):
self.ActiveState = 'inactive'
class PlaceholderYoloUnit(object):
def __init__(self):
self.Unit = PlaceholderUnit()
class McUnit:
"""
A class to represent a Unit of the minecraft service.
The factory function discover_units expects to find installations of
Minecraft Server in folders under /home/minecraft/MinecraftServers
and returns a list of McUnit
"""
repr_format = "{:3.2s}{:20.19s}{:11.10s}{:8.7s}{:9.8s}{:10.9s}{:15.14s}{:4.4s}"
heading = repr_format.format("No", "Name", "State", "SubSt", "Auto Start",
"GameMode", "World", "Wlds")
config_name = "server.properties"
# keep a dbus and a manager for the lifetime of the class/app
dbus = DBus(user_mode=True)
dbus.open()
manager = Manager(bus=dbus)
manager.load()
def __init__(self, name, unit, unit_name, num):
self.name = name
self.unit = unit
self.unit_name = unit_name
self.num = num
self.config_path = Config.mc_root / name / self.config_name
self.properties = Properties(self.config_path)
self.properties.read()
self.world = self.properties["level-name"]
self.mode = self.properties["gamemode"]
self.worlds = [
f.name for f in (Config.mc_root / name).iterdir()
if f.name not in Config.non_worlds and f.is_dir()
]
@classmethod
def discover_units(cls):
# factory function that queries systemd files and returns a list
# of McUints (1 systemd unit per Minecraft installation)
mc_installs = list(Config.mc_root.glob("*"))
mc_names = [
str(mc.name) for mc in mc_installs
if not str(mc.name).startswith(".")
]
units = []
for i, mc_name in enumerate(mc_names):
unit_name = Config.unit_name_format.format(mc_name)
unit = Unit(unit_name.encode("utf8"), bus=cls.dbus)
unit.load()
units.append(McUnit(mc_name, unit, unit_name, i))
return units
def __repr__(self):
state = self.unit.Unit.ActiveState.decode("utf8")
sub_state = self.unit.Unit.SubState.decode("utf8")
enabled = self.manager.Manager.GetUnitFileState(
self.unit_name).decode()
return self.repr_format.format(str(self.num), self.name, state,
sub_state, enabled, self.mode,
self.world, str(len(self.worlds)))
def get_world_path(self, world_num):
if not len(self.worlds) >= world_num >= 0:
raise ValueError(f"world number {world_num} does not exist")
return Config.mc_root / self.name / self.worlds[world_num]
def set_world(self, world_num):
self.properties.read()
if not len(self.worlds) >= world_num >= 0:
raise ValueError(f"world number {world_num} does not exist")
self.properties["level-name"] = self.worlds[world_num]
self.properties.write()
self.world = self.worlds[world_num]
def start(self):
print(f"Starting {self.name} ...")
self.unit.Start(b"replace")
def stop(self):
print(f"Stopping {self.name} ...")
self.unit.Stop(b"replace")
# wait for the service to complete termination
while self.running:
sleep(.2)
def restart(self):
# unit.Restart does not work for some reason
self.stop()
self.start()
def enable(self):
self.manager.Manager.EnableUnitFiles([self.unit_name], False, False)
def disable(self):
self.manager.Manager.DisableUnitFiles([self.unit_name], False)
def console(self):
cmd = Config.screen_cmd_format.format(self.name)
os.system(cmd)
@property
def running(self):
state = self.unit.Unit.ActiveState.decode("utf8")
return state != "inactive"
actions = {
"s": start,
"k": stop,
"e": enable,
"d": disable,
"r": restart,
"c": console,
}