hio.base.hier.holding
=====================

.. py:module:: hio.base.hier.holding

.. autoapi-nested-parse::

   hio.hold.holding Module

   Provides durable data storage with LMDB





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

.. py:class:: Hold(*pa, **kwa)

   Bases: :py:obj:`hio.help.Mine`


   Hold is Mine subclass that on writes intercepts key and keys and then
   also saves updates value in durable storage for value object CanDom and Durq
   serializations

   Hold has special item '_hold_subery' whose value is Subery instance or None.
   Read access is provided via the property .subery

   Subery attributes are the subdbs:
   .cans
   .dsqs

   Hold injects reference to one of these based on the type of value and the Hold
   key  into ._sdb and ._key.  When not a durable value then no injection.
   This allows the value then to read/write to its ._sdb at ._key the fields
   of the Can when Can or Durq when Durq


   Properties::

       subery (None|Subery): gets instance from item at '_hold_subery' or None

   .. method:: - inject

      injects .cans into val._sdb and key into val._key
      
      
      


   .. py:method:: update(*pa, **kwa)

      Convert keys that are tuples when positional argument is Iterable or
      Mapping to '.' joined strings

      dict __init__ signature options are:
          ``dict(**kwa)``
          ``dict(mapping, **kwa)``
          ``dict(iterable, **kwa)``
      dict.update has same call signature
          d.update({"a": 5, "b": 2,}, c=3 , d=4)




   .. py:method:: inject(key, val)

      When val is instance of CanDom, injects .tokey(key) into val._key and
      .subery.cans into val._sdb

      Parameters::

          key (str): for item
          val (Any|CanDom): for item. When instance subclass of CanDom then
              inject to ._key and ._sdb



   .. py:property:: subery

      Gets value of special item '_hold_subery'

      Returns::

          subery (None|Subery): instance or None