DKNet.AspCore.Idempotency.RedisStore 10.1.18

DKNet.AspCore.Idempotency.RedisStore

A Redis-backed idempotency key store for DKNet.AspCore.Idempotency. Implements the store contract directly against StackExchange.Redis — no schema, no migrations, and expiry falls out of Redis's own TTL.

Features

• Atomic request reservation via SET NX — exactly one concurrent caller per idempotency key proceeds
• SHA-256 hashed, prefixed Redis keys so distinct composite keys never collide
• Native TTL-based expiry for both in-flight reservations and completed responses
• Reuses an existing IConnectionMultiplexer/IDistributedCache, or registers its own from a connection string

Installation

dotnet add package DKNet.AspCore.Idempotency.RedisStore

Quick Start

using DKNet.AspCore.Idempotency;
using DKNet.AspCore.Idempotency.RedisStore;

var builder = WebApplication.CreateBuilder(args);

builder.Services.AddIdempotencyWithRedisStore(
    builder.Configuration.GetConnectionString("Redis")!,
    options =>
    {
        options.Expiration = TimeSpan.FromHours(48);
        options.ConflictHandling = IdempotentConflictHandling.CachedResult;
    });

var app = builder.Build();

app.MapPost("/orders", () => Results.Ok())
    .RequiredIdempotentKey();

app.Run();

Clients send an X-Idempotency-Key header on POST /orders; a retry with the same key replays the first response instead of creating a second order.

Customisation reference

There is no Redis-specific options type. AddIdempotencyWithRedisStore configures the shared IdempotencyOptions from DKNet.AspCore.Idempotency:

Values are validated eagerly at registration: an empty header key or cache prefix, a non-positive expiration, a status-code window outside 100–599 or with min above max, a null JsonSerializerOptions, a MaxIdempotencyKeyLength below 1, an empty key pattern, or a whitespace ScopeHmacSecret each throw ArgumentException immediately rather than failing at request time.

Of those, this store reads CachePrefix (Redis key prefix), Expiration (TTL on a completed response), InFlightReservationTimeout (TTL on a SET NX reservation) and JsonSerializerOptions (the stored value's format). The rest are applied by the endpoint filter before the store is called.

Fixed by this package, not exposed as options

You provide a reachable Redis instance, its memory sizing and its eviction policy. There is no schema, no migration and no cleanup job — expiry is Redis's own TTL. An eviction under memory pressure silently makes a key look new again.

Registration entry points

IdempotencyRedisStore is internal, so AddIdempotentKey<IdempotencyRedisStore>() does not compile in application code — AddIdempotencyWithRedisStore(...) is the supported way in. Pass an existing multiplexer to the second overload first if you do not want this package connecting one of its own.

Documentation

Full feature reference: https://github.com/baoduy/DKNet/blob/main/docs/AspNetCore/DKNet.AspCore.Idempotency.RedisStore.md

License

MIT — see LICENSE.

About

Developed by Steven Hoang.