[ERP-4395] Cache schema to improve perfomance and reduce memory use

[ScriptSmith]

No description provided.

[Copilot]

Pull request overview

This PR aims to improve GraphQL performance by caching the dynamically generated Graphene schema and invalidating that cache when registry definitions change.

Changes:

• Memoize create_dynamic_schema() using cache_memoize and add clear_dynamic_schema_cache().
• Invalidate the schema cache on registry form/section/CDE changes.
• Add new signal receivers intended to invalidate the schema cache on Registry / ContextFormGroup changes.

Reviewed changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated 2 comments.

File	Description
rdrf/report/schema.py	Adds memoization to the dynamic schema builder and exposes an explicit cache invalidation hook.
rdrf/rdrf/models/definition/models.py	Hooks schema cache invalidation into model lifecycle events via Django signals.

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[Copilot]

@cache_memoize uses the Django cache backend (db/memcached/etc) and will pickle the return value. A graphene.Schema built from dynamically created types and local resolver functions (closures/partials) is not pickleable, so caching create_dynamic_schema() this way is likely to raise a PicklingError at runtime when the decorator attempts to cache the schema.

Suggested fix: use a per-process in-memory cache (e.g., functools.lru_cache(maxsize=1) or a module-level singleton) and update clear_dynamic_schema_cache() to call cache_clear()/reset the module variable. If you truly need cross-process caching, cache a serializable representation (e.g., SDL) rather than the Schema object itself.

[Copilot]

The signal senders for registry_definition_changed are specified as strings ("definition.Registry" and "definition.ContextFormGroup"), but the actual model labels in this project appear to be under the rdrf app (e.g., settings installs the rdrf app, and other code references these models as "rdrf.Registry" / "rdrf.ContextFormGroup"). As written, this receiver likely never fires, so the dynamic schema cache won’t be invalidated when registries or context form groups change.

Suggested fix: use the model classes directly (sender=Registry / sender=ContextFormGroup) or update the string labels to "rdrf.Registry" and "rdrf.ContextFormGroup". It would also be good to add a test that creates/updates a ContextFormGroup or Registry and asserts create_dynamic_schema() reflects the change after invalidation.

Suggested change

	@receiver([post_save, post_delete], sender="definition.Registry")
	@receiver([post_save, post_delete], sender="definition.ContextFormGroup")
	@receiver([post_save, post_delete], sender=Registry)
	@receiver([post_save, post_delete], sender=ContextFormGroup)