@meridianjs/event-bus-redis

Production-grade event bus for MeridianJS, backed by BullMQ + Redis. Provides durable, at-least-once, async event delivery across multiple processes or servers.

For local development without Redis, use @meridianjs/event-bus-local instead.

Installation

npm install @meridianjs/event-bus-redis

Configuration

Register in meridian.config.ts:

export default defineConfig({
  modules: [
    {
      resolve: "@meridianjs/event-bus-redis",
      options: { url: process.env.REDIS_URL },
    },
  ],
})

| Option | Type | Default | Description | |---|---|---|---| | url | string | — | Redis connection URL (required) | | queueName | string | "meridian:events" | BullMQ queue name | | concurrency | number | 5 | Worker concurrency |

Behaviour

• All events are published to a single persistent BullMQ queue.
• A worker processes jobs and fans out to all in-process subscribers for the event name.
• Failed jobs are retried up to 3 times with exponential back-off (1 s base).
• Completed jobs are retained for the last 1 000 entries; failed jobs for 500.
• The queue, worker, and Redis connection are all gracefully closed when the application stops.

Switching from Local

The event bus interface is the same across both implementations:

// development
{ resolve: "@meridianjs/event-bus-local" }

// production
{ resolve: "@meridianjs/event-bus-redis", options: { url: process.env.REDIS_URL } }

Direct Usage

import type { IEventBus } from "@meridianjs/types"

const eventBus = container.resolve("eventBus") as IEventBus

await eventBus.emit([
  { name: "issue.created",       data: { issueId: "..." } },
  { name: "activity.recorded",   data: { actorId: "..." } },
])

License

MIT