httk.serve.optimade.backend.stores
==================================

.. py:module:: httk.serve.optimade.backend.stores

.. autoapi-nested-parse::

   Build an OPTIMADE adapter over lazy SQL-backed entry federation.

   The durable layout, SQL translation, collision policy, and bounded global
   pagination live in :mod:`httk.store.db`.  This module owns only the serving
   boundary: the advertised OPTIMADE schema, request-error translation, public
   response-field projection, and :class:`~httk.serve.optimade.model.ResultRow`
   objects consumed by the endpoint envelope code.

   Imports from ``httk.store.db`` deliberately remain inside call sites.  Importing
   ``httk.serve.optimade`` therefore does not initialize a database backend or
   load optional SQL dialects.



Classes
-------

.. autoapisummary::

   httk.serve.optimade.backend.stores.StoredBackendAdapter


Functions
---------

.. autoapisummary::

   httk.serve.optimade.backend.stores.adapter_from_stores
   httk.serve.optimade.backend.stores.adapter_from_store


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

.. py:class:: StoredBackendAdapter

   Serve one data federation per OPTIMADE entry type.

   :param federations: Durable federations keyed by entry endpoint.
   :param schema: Schema describing the federations' served entries.


   .. py:attribute:: federations
      :type:  collections.abc.Mapping[str, Any]


   .. py:attribute:: schema
      :type:  httk.serve.optimade.schema.served.ServedSchema


   .. py:method:: snapshot_cutoff_ns(entry_type, now_ns)

      Return the resolution-aware snapshot cutoff for one entry type.



   .. py:method:: query_function()

      Return the callback that queries the configured federations.

      :return: Query callback consumed by the OPTIMADE request engine.



.. py:function:: adapter_from_stores(sources, **options)

   Build a lazy store-backed adapter from durable entry sources.

   Sources with the same exact logical family are federated under one entry
   endpoint.  The data layer owns all source/backing traversal and global
   pagination; this adapter advertises the family's definition and turns only
   the returned page into OPTIMADE result rows.

   :param sources: Durable entry sources to federate by entry type.
   :param \*\*options: Schema options forwarded to :func:`~httk.serve.optimade.schema.served.build_served_schema`.
   :return: Lazy adapter over the supplied durable sources.
   :raises ValueError: If sources conflict or expose incomplete sort mappings.
   :raises TypeError: If a source is not a stored entry source.


.. py:function:: adapter_from_store(store, **options)

   Build a lazy OPTIMADE adapter from every described family in one store.

   Families declared without an entry-type definition are deliberately
   ignored.  This lets application-specific records, such as DSP publication
   declarations, coexist with OPTIMADE records in one durable layout.

   :param store: Entry store whose configured layout is discovered.
   :param \*\*options: Schema options forwarded to :func:`adapter_from_stores`.
   :return: Lazy adapter over all configured OPTIMADE families.
   :raises TypeError: If ``store`` does not implement :class:`EntryStore`.
   :raises ValueError: If the store contains no OPTIMADE-described family.