Attribute Reference

[Cache]

[Cache(TtlMs = 60_000, Sliding = false, MaxEntries = 0, UseHybridCache = false)]

Property	Type	Default	Description
TtlMs	int	required	Cache entry lifetime in milliseconds
Sliding	bool	false	When true, the TTL is reset on each access (sliding expiration). Ignored by the L2 tier when UseHybridCache = true — see ZC0001
MaxEntries	int	0 (unlimited)	When greater than zero, the method gets its own isolated MemoryCache instance with this value as its SizeLimit. Useful for bounding memory on high-cardinality methods
UseHybridCache	bool	false	When true, uses Microsoft.Extensions.Caching.Hybrid instead of IMemoryCache. Requires HybridCache to be registered in DI

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Interface-level vs method-level overrides

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[Cache] can be placed on the interface, on individual methods, or on both.

Interface-level only — all methods use the same policy:

[Cache(TtlMs = 60_000)]
public interface IProductRepository
{
    ValueTask<Product?> GetByIdAsync(int id, CancellationToken ct);
    ValueTask<IReadOnlyList<Product>> ListAllAsync(CancellationToken ct);
}

Method-level override — the method attribute shadows the interface attribute entirely for that method. The properties are not merged:

[Cache(TtlMs = 60_000)]
public interface IProductRepository
{
    // uses interface-level: 60 s, IMemoryCache, unlimited entries
    ValueTask<Product?> GetByIdAsync(int id, CancellationToken ct);

    // overrides entirely: 5 min, bounded cache, sliding
    [Cache(TtlMs = 300_000, MaxEntries = 500, Sliding = true)]
    ValueTask<IReadOnlyList<Product>> SearchAsync(string query, CancellationToken ct);
}

Method-level only (no interface attribute) — only annotated methods are cached; unannotated methods are forwarded directly to the inner implementation:

public interface IProductRepository
{
    [Cache(TtlMs = 60_000)]
    ValueTask<Product?> GetByIdAsync(int id, CancellationToken ct);

    // not cached — forwarded directly to inner implementation
    ValueTask SaveAsync(Product product, CancellationToken ct);
}

Method-level attributes shadow interface-level ones — they are not additive. If you set TtlMs at the interface and only specify MaxEntries at the method level, TtlMs is not inherited; you must repeat it.