patroni.postgresql.callback_executor module

class patroni.postgresql.callback_executor.CallbackAction(value)

Bases: str, enum.Enum

An enumeration.

NOOP = 'noop'
ON_RELOAD = 'on_reload'
ON_RESTART = 'on_restart'
ON_ROLE_CHANGE = 'on_role_change'
ON_START = 'on_start'
ON_STOP = 'on_stop'
_generate_next_value_(start, count, last_values)

Generate the next value when not given.

name: the name of the member start: the initial start value or None count: the number of existing members last_value: the last value assigned or None

_member_map_ = {'NOOP': CallbackAction.NOOP, 'ON_RELOAD': CallbackAction.ON_RELOAD, 'ON_RESTART': CallbackAction.ON_RESTART, 'ON_ROLE_CHANGE': CallbackAction.ON_ROLE_CHANGE, 'ON_START': CallbackAction.ON_START, 'ON_STOP': CallbackAction.ON_STOP}
_member_names_ = ['NOOP', 'ON_START', 'ON_STOP', 'ON_RESTART', 'ON_RELOAD', 'ON_ROLE_CHANGE']
_member_type_

alias of str

_value2member_map_ = {'noop': CallbackAction.NOOP, 'on_reload': CallbackAction.ON_RELOAD, 'on_restart': CallbackAction.ON_RESTART, 'on_role_change': CallbackAction.ON_ROLE_CHANGE, 'on_start': CallbackAction.ON_START, 'on_stop': CallbackAction.ON_STOP}
class patroni.postgresql.callback_executor.CallbackExecutor

Bases: patroni.postgresql.cancellable.CancellableExecutor, threading.Thread

__init__()

This constructor should always be called with keyword arguments. Arguments are:

group should be None; reserved for future extension when a ThreadGroup class is implemented.

target is the callable object to be invoked by the run() method. Defaults to None, meaning nothing is called.

name is the thread name. By default, a unique name is constructed of the form “Thread-N” where N is a small decimal number.

args is the argument tuple for the target invocation. Defaults to ().

kwargs is a dictionary of keyword arguments for the target invocation. Defaults to {}.

If a subclass overrides the constructor, it must make sure to invoke the base class constructor (Thread.__init__()) before doing anything else to the thread.

call(cmd: List[str]) None

Executes one callback at a time.

Already running command is killed (including child processes). If it couldn’t be killed we wait until it finishes.

Parameters

cmd – command to be executed

run() None

Method representing the thread’s activity.

You may override this method in a subclass. The standard run() method invokes the callable object passed to the object’s constructor as the target argument, if any, with sequential and keyword arguments taken from the args and kwargs arguments, respectively.

class patroni.postgresql.callback_executor.OnReloadExecutor

Bases: patroni.postgresql.cancellable.CancellableSubprocess

call_nowait(cmd: List[str]) None

Run one on_reload callback at most.

To achieve it we always kill already running command including child processes.