Cache Key Providers

Cache Key Providers

Use ICacheKeyProvider<T> when a request object needs a stable cache key shape that is different from its default structural form.

Why this exists

Most request objects can be cached directly, but complex members such as expressions, iterators, or other non-ideal object graphs can produce noisy or unstable keys. A type-specific provider lets you reduce the key to the fields that actually define cache identity.

Use this when the default object-based key is too broad, too noisy, or not obviously stable across runs. Typical cases are:

• queries that contain Expression trees
• requests that carry deferred IEnumerable values
• objects with members that are only useful for execution, not identity
• requests where only a subset of fields should affect cache identity

Don’t use it for simple request records that already map cleanly to a stable structural key; the default path is simpler and usually good enough there.

Register a provider

public sealed class GetLeadSourceBrandsQueryKeyProvider
    : ICacheKeyProvider<GetLeadSourceBrandsQuery>
{
    public object GetKey(GetLeadSourceBrandsQuery value)
        => new { value.LeadSourceId };
}

builder.Services.AddCleverCache(o =>
    o.AddKeyProvider<GetLeadSourceBrandsQuery, GetLeadSourceBrandsQueryKeyProvider>());

Scan for providers

If you prefer discovery over explicit registration, use:

builder.Services.AddCleverCache(o =>
    o.ScanKeyProviderAssemblies<GetLeadSourceBrandsQuery>());

or:

builder.Services.AddCleverCache(o =>
    o.ScanKeyProviderAssemblies(typeof(GetLeadSourceBrandsQuery).Assembly));

Notes

• Providers are resolved by runtime type and cached in memory.
• Keep the returned key stable and deterministic.
• For simple request shapes, the default structural key generation is usually enough.
• If CleverCache still cannot produce a stable key, it logs a warning and skips caching for that call rather than risking a bad cache entry.