Redis Provider

The Redis provider stores idempotency records in a distributed cache, making it suitable for applications running on multiple instances.

It is the recommended provider for most production workloads that require low latency and horizontal scalability.

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When to Use Redis

Use the Redis provider when your application:

• Runs on multiple instances
• Is deployed to Kubernetes
• Requires low-latency request processing
• Needs distributed idempotency
• Can tolerate data loss after Redis persistence policies

If long-term durability is required, consider the PostgreSQL provider instead.

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Configuration

Configure Redis in your application settings.

{
  "ConnectionStrings": {
    "Redis": "localhost:6379"
  },
  "Core": {
    "Idempotency": {
      "Provider": "Redis"
    }
  }
}

Register the framework:

builder.Services.AddCoreIdempotency(options =>
{
    builder.Configuration
        .GetSection("Core:Idempotency")
        .Bind(options);
});

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How It Works

When a request reaches the middleware:

1. The request fingerprint is generated.
2. Redis is queried using the idempotency key.
3. If the key exists:
4. The stored fingerprint is validated.
5. The cached response is returned.
6. Otherwise:
7. The request executes normally.
8. The response is stored in Redis.
9. The response is returned to the client.

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Expiration

Stored responses automatically expire after the configured expiration period.

options.Expiration =
    TimeSpan.FromHours(24);

After expiration, the request is treated as a new operation.

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Production Recommendations

✅ Deploy Redis in a highly available configuration.

✅ Configure persistence according to your recovery requirements.

✅ Monitor memory usage and eviction policies.

✅ Use dedicated Redis instances for production workloads whenever possible.

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Limitations

Redis is an in-memory data store.

Depending on its persistence configuration, data may be lost after an unexpected restart.

Applications that require durable storage should use the PostgreSQL provider.

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Related Documentation

• Configuration
• PostgreSQL Provider
• Fingerprinting
• Response Replay