Signals

Attributes

REGISTERED_SIGNALS

REGISTERED_SIGNALS: dict[int, SignalDescription] = {}

Registered signals.

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Functions

get_available_num

get_available_num() -> int

Returns first available signal number.

UwsgiconfException If no signal is available.

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get_last_received

get_last_received() -> Signal

Get the last signal received.

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Classes

Signal

Signal(num: int | None = None)

Represents uWSGI signal.

Warning

If you define a new function in worker1 and register it as a signal handler, only worker1 can run it. The best way to register signals is defining them in the master (.runtime.uwsgi.postfork_hooks.add), so all workers see them.

signal = Signal()

@signal.register_handler()
def somefunc():
    pass

# or the same:

@signal
def somefunc():
    pass

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registered

.registered()

Whether the signal is registered.

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register_handler

.register_handler(
    target: TypeTarget = None,  # (1)!
    callback: Callable[[Signal],  None] | None = None,  # (2)!
) -> Callable

1. Where this signal will be delivered to. Default: worker.

   * Mule / Farm object - run on a certain mule or a farm.
   * ``workers``  - run the signal handler on all the workers
   * ``workerN`` - run the signal handler only on worker N
   * ``worker``/``worker0`` - run the signal handler on the first available worker
   * ``active-workers`` - run the signal handlers on all the active [non-cheaped] workers
   
   * ``mules`` - run the signal handler on all the mules
   * ``muleN`` - run the signal handler on mule N
   * ``mule``/``mule0`` - run the signal handler on the first available mule
   
   * ``spooler`` - run the signal on the first available spooler
   * ``farmN/farm_XXX``  - run the signal handler in the mule farm N or named XXX
   
   * <http://uwsgi.readthedocs.io/en/latest/Signals.html#signals-targets>
   

2. Function to be called after the registration.

Decorator for a function to be used as a signal handler.

signal = Signal()

@signal.register_handler()
def somefunc():
    pass

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send

.send(
    remote: str | None = None,  # (1)!
)

1. Remote address.

Sends the signal to master or remote.

When you send a signal, it is copied into the master's queue. The master will then check the signal table and dispatch the messages.

ValueError If remote rejected the signal.

OSError If unable to deliver to remote.

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wait

.wait()

Waits for the given of any signal.

Block the process/thread/async core until a signal is received. Use signal_received to get the number of the signal received. If a registered handler handles a signal, signal_wait will be interrupted and the actual handler will handle the signal.

• http://uwsgi-docs.readthedocs.io/en/latest/Signals.html#signal-wait-and-signal-received

SystemError If something went wrong.

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SignalDescription

SignalDescription()

NamedTuple

Registered signal information.

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func

.func: Callable

Function to run on signal.

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num

.num: int

Signal number.

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target

.target: str

Target: worker, mule, etc.

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