state_machine

State machine for parsing systemd unit journal entries.

Classes:

• State –

  Abstract base class for state machine states.

• SystemdUnitStateChange –

  Event emitted when a systemd unit changes state.

• SystemdUnitStateMachine –

  State machine for tracking a systemd unit's state via journal entries.

State dataclass

State()

Bases: ABC

Abstract base class for state machine states.

Returned by:

• API Reference linuxptp_monitor
  •  phc2sys_instance  Phc2SysRunningState  parse
  •  state_machine
    •  State  parse
    •  SystemdUnitStateMachine  Uninitialized  parse

Subclassed by:

• API Reference linuxptp_monitor
  •  phc2sys_instance  Phc2SysRunningState
  •  ptp4l_instance  Ptp4lRunningState
  •  state_machine  SystemdUnitStateMachine  Uninitialized

Used by:

• API Reference linuxptp_monitor  state_machine
  •  SystemdUnitStateChange
  •  SystemdUnitStateMachine

Methods:

• parse –

  Parse a journal entry and yield events, returning the next state.

parse abstractmethod

parse(entry: JournalEntry) -> Generator[Event, None, State]

Parse a journal entry and yield events, returning the next state.

SystemdUnitStateChange dataclass

SystemdUnitStateChange(old_state: State, new_state: State)

Event emitted when a systemd unit changes state.

Attributes:

• old_state (State) –

  The previous state.

• new_state (State) –

  The new state.

Returned by:

• API Reference linuxptp_monitor  state_machine  SystemdUnitStateMachine  consume

Used by:

• API Reference diag_worker
  •  phc2sys_monitor_task  Phc2SysMonitorTask  phc2sys_to_graph_updates
  •  ptp4l_monitor_task  Ptp4lMonitorTask  ptp4l_to_graph_updates

SystemdUnitStateMachine

SystemdUnitStateMachine(
    inner_state_factory: Callable[[], State | None],
    inner_state_on_exit: Callable[[State], None],
    unit_name: str,
)

State machine for tracking a systemd unit's state via journal entries.

Parameters:

• inner_state_factory (Callable[[], State | None]) –

  Factory to create the running state.

• inner_state_on_exit (Callable[[State], None]) –

  Callback when the unit stops.

• unit_name (str) –

  The systemd unit name to monitor.

Classes:

• Uninitialized –

  State before the unit has started or after it stopped.

Methods:

• consume –

  Process journal entries, yielding events and state changes.

Uninitialized dataclass

Uninitialized(factory: Callable[[], State | None])

Bases: State

State before the unit has started or after it stopped.

Attributes:

• factory (Callable[[], State | None]) –

  Factory function to create the initial running state. Called when the unit starts. Can be called multiple times if the unit restarts.

Methods:

• __eq__ –

  Check equality with another Uninitialized state.

• parse –

  Try to instantiate an initial state, and parse the incoming entry with it.

__eq__

__eq__(value: object) -> bool

Check equality with another Uninitialized state.

parse

parse(entry: JournalEntry) -> Generator[Event, None, State]

Try to instantiate an initial state, and parse the incoming entry with it.

consume

consume(
    entries: list[JournalEntry],
) -> Generator[Event | SystemdUnitStateChange, None, None]

Process journal entries, yielding events and state changes.