Decorators
==========

Reusable decorators that add cross-cutting behaviour (caching, retries, …)
to any callable.  Unlike the Lambda-specific decorators under
:doc:`/services/lambdas/decorators`, these are framework-agnostic and work
with plain functions, ETL methods, or any other callable.

.. note::

   **Serialization format (pickle)**

   Cached values are serialized with Python's :mod:`pickle` module.  Bandit
   flags ``pickle`` by default (rules B403 and B301) because deserializing
   data from an *untrusted* source can execute arbitrary code.

   That risk does not apply here: the only data ever passed to
   ``pickle.loads()`` is data that *this library* previously wrote with
   ``pickle.dumps()``.  There is no user-controlled input anywhere in the
   deserialization path, so the Bandit warnings are suppressed with
   ``# nosec B403`` / ``# nosec B301``.

   **Do not point these decorators at S3 objects or DynamoDB items that are
   writable by untrusted parties.**

.. toctree::
   :maxdepth: 1

   cache_dynamo_based
   cache_s3_based