Declarative read-through caching for Ash read and generic actions. See AshCache.Resource for the DSL and README.md in this directory for the design.

These helpers are the runtime escape hatch for operational situations (a support task, a migration) that need to reach past the declarative layer.

Telemetry

Seven :telemetry events let you assert cache behaviour in tests and measure hit rates in production. All have empty measurements. Calls that are bypassed, or not cached, emit nothing. Actor and tenant are never in the metadata.

• [:ash_cache, :read, :hit] - a cached read was answered without the data layer: from the store, or with the records of an identical read running at the same time (see AshCache.Coalesce). Metadata: :resource, :action, :store.
• [:ash_cache, :read, :miss] - a cached read was not in the store and went to the data layer. Metadata: :resource, :action, :store, and :error, which is nil normally or the reason when the store failed to answer (the read still goes through).
• [:ash_cache, :action, :hit] and [:ash_cache, :action, :miss] - the same for a cached generic action, with the same metadata. A miss means the action's run was called.
• [:ash_cache, :calculation, :hit] and [:ash_cache, :calculation, :miss] - the same for one record of a cached calculation (see AshCache.Calculations.CalculateThrough), with :calculation in place of :action. A miss means the calculation ran for that record.
• [:ash_cache, :invalidate] - a resource's cache was invalidated, by a successful create, update or destroy or by invalidate/1. Metadata: :resource, :store.