hio.base.hier.durqing
=====================

.. py:module:: hio.base.hier.durqing

.. autoapi-nested-parse::

   hio.base.hier.durqing Module

   Provides durable  queue for hold hierarchical actions





Module Contents
---------------

.. py:class:: Durq(*pa)

   Durq (durable queue) class when injected with
   .sdb and .key will store its ordered list durably and allow access as a FIFO
   queue

   Properties:
       stale (bool): True means in-memory and durable on disk not synced.
           False means in-memory and durable on disk synced.
       durable (bool): True means ._sdb and ._key and ._sdb.db and
           ._sdb.db.opened are not None.
           False otherwise.

   Hidden:
      _deq (deque): in-memory cache as deque
      _sdb (DomIoSuber): instance of durable store
      _key (str): into .sdb
      _stale (bool): stale-status cache for .stale property.



   .. py:property:: stale

      Getter for ._stale

      :returns: True means in-memory and durable on disk not synced; False means in-memory and durable on disk synced
      :rtype: stale (bool)


   .. py:property:: durable

      Property durable True when durable subdb injected and opened.

      Returns::

          durable (bool): True means ._sdb and ._key and ._sdb.db and
              ._sdb.db.opened are not None
              False otherwise


   .. py:method:: extend(vals: hio.help.NonStringIterable[hio.help.RegDom | hio.help.IceRegDom])

      Extend ._deq with vals
      Performs equivalent operation on durable .sdb at .key if any




   .. py:method:: push(val: hio.help.RegDom | hio.help.IceRegDom)

      If not None, add val to last in. Otherwise ignore
      Performs equivalent operation on durable .sdb at .key if any

      :param val: element to be appended to deck (deque)
      :type val: hio.help.doming.RegDom



   .. py:method:: pull(emptive=True)

      Remove and return first in value
      If empty and emptive return None else raise IndexError

      Performs equivalent operation on durable .sdb at .key if any

      Parameters::

          emptive (bool): True means return None instead of raise IndexError
             when attempt to pull
             False means normal behavior of deque



   .. py:method:: clear()

      Clear all values from deque
      Performs equivalent operation on durable .sdb at .key if any




   .. py:method:: count(value)

      Returns count of entries in ._deq equal to value




   .. py:method:: put(vals: hio.help.NonStringIterable[hio.help.RegDom | hio.help.IceRegDom])

      Put (append) vals to .sdb at .key if any



   .. py:method:: add(val)

      Add value to .sdb at .key if any



   .. py:method:: pop()

      Pop value from .sdb at .key if any



   .. py:method:: rem()

      Remove all values from .sdb at .key if any



   .. py:method:: cnt()

      Count all values in .sdb at .key if any



   .. py:method:: pin()

      Pins all of ._deq to ._sdb at ._key if any.
      Sets ._stale to False on success



   .. py:method:: sync(force=False)

      Syncs by checking exists durable copy in ._sdb at ._key. If so
      and ._stale or force then reads own data from ._sdb at ._key if any.
      If not attempts to write to ._sdb at ._key

      Parameters::
          force (bool): True means force read even if not ._stale
                        False means do not force read