Redis Idempotency Store

The redis.IdempotencyStore implements the invoker.IdempotencyStore interface using Redis for distributed duplicate detection.

Setup

import (
    "github.com/redis/go-redis/v9"
    eventredis "github.com/isaquesb/go-event-bus/redis"
)

rdb := redis.NewClient(&redis.Options{
    Addr: "localhost:6379",
})

store := eventredis.NewIdempotencyStore(rdb)

Use with the idempotency invoker:

invoker.NewIdempotency(store, invoker.IdempotencyConfig{
    ProcessingTTL: 5 * time.Minute,
}, metrics)

Redis Key Structure

Keys follow the pattern: {idempotency_key}:{handler_name}

Example: order:order-12345:process-order

Value

JSON-encoded IdempotencyRecord:

{"status": "completed", "started_at": "2026-02-05T12:00:00Z", "ended_at": "2026-02-05T12:00:01Z"}

TTL by Status

Status	TTL	Rationale
processing	5 minutes	Lock recovery for crashed pods
completed	24 hours	Duplicate prevention window
failed	1 hour	Allow retry after failure

Operations

Put

Uses SET with TTL based on status. Overwrites existing values (used when transitioning from “processing” to “completed”/”failed”).

Get

Uses GET. Returns (record, true, nil) if found, (empty, false, nil) if not found.

Delete

Uses DEL to remove a key.

Stale Lock Recovery

If a pod crashes while processing (status = “processing”), the TTL ensures the lock expires after 5 minutes. The idempotency invoker detects stale locks and re-acquires them.