---
title: Configuration
description: Config structs, YAML examples, and option helpers for Events
---

## YAML Configuration Example

```yaml title="config.yaml"
extensions:
  events:
    bus:
      defaultBroker: "memory"       # default broker for Publish()
      maxRetries: 3
      retryDelay: "5s"
      enableMetrics: true
      enableTracing: false
      bufferSize: 1000              # event channel buffer
      workerCount: 10               # concurrent event workers
      processingTimeout: "30s"

    store:
      type: "memory"                # "memory", "postgres", "mongodb"
      database: ""                  # database connection name (for postgres/mongodb)
      table: "events"               # events table/collection name

    brokers:
      - name: "memory"
        type: "memory"
        enabled: true
        priority: 1

      - name: "nats"
        type: "nats"
        enabled: true
        priority: 2
        config:
          url: "nats://localhost:4222"
          clusterID: "my-cluster"

      - name: "redis"
        type: "redis"
        enabled: false
        priority: 3
        config:
          url: "redis://localhost:6379"

    metrics:
      enabled: true
      publishInterval: "30s"
      enablePerType: true
      enablePerHandler: true
```

The extension loads config from `extensions.events` first, falling back to `events`.

## Programmatic Configuration

```go
ext := events.NewExtensionWithConfig(events.Config{
    Bus: events.BusConfig{
        DefaultBroker: "memory",
        WorkerCount:   20,
        BufferSize:    5000,
    },
    Store: events.StoreConfig{
        Type:  "memory",
        Table: "events",
    },
    Brokers: []events.BrokerConfig{
        {Name: "memory", Type: "memory", Enabled: true, Priority: 1},
    },
})
```

## Config Struct Reference

### `Config`

| Field | Type | Default | Description |
|---|---|---|---|
| `Bus` | `BusConfig` | See below | Event bus configuration |
| `Store` | `StoreConfig` | See below | Event store configuration |
| `Brokers` | `[]BrokerConfig` | Memory broker | Message broker definitions |
| `Metrics` | `MetricsConfig` | See below | Metrics collection settings |

### `BusConfig`

| Field | Type | Default | Description |
|---|---|---|---|
| `DefaultBroker` | `string` | `"memory"` | Default broker for `Publish()` |
| `MaxRetries` | `int` | `3` | Retry attempts for failed publishes |
| `RetryDelay` | `time.Duration` | `5s` | Delay between retries |
| `EnableMetrics` | `bool` | `true` | Emit bus metrics |
| `EnableTracing` | `bool` | `false` | Enable distributed tracing |
| `BufferSize` | `int` | `1000` | Internal event channel buffer size |
| `WorkerCount` | `int` | `10` | Number of concurrent event workers |
| `ProcessingTimeout` | `time.Duration` | `30s` | Timeout per event processing |

### `StoreConfig`

| Field | Type | Default | Description |
|---|---|---|---|
| `Type` | `string` | `"memory"` | Store backend: `"memory"`, `"postgres"`, `"mongodb"` |
| `Database` | `string` | `""` | Database connection name |
| `Table` | `string` | `"events"` | Table or collection name |

### `BrokerConfig`

| Field | Type | Description |
|---|---|---|
| `Name` | `string` | Unique broker identifier |
| `Type` | `string` | Broker type: `"memory"`, `"nats"`, `"redis"` |
| `Enabled` | `bool` | Whether this broker is active |
| `Priority` | `int` | Selection priority (lower = higher priority) |
| `Config` | `map[string]any` | Broker-specific settings |

### `MetricsConfig`

| Field | Type | Default | Description |
|---|---|---|---|
| `Enabled` | `bool` | `true` | Enable metrics collection |
| `PublishInterval` | `time.Duration` | `30s` | Metrics publishing interval |
| `EnablePerType` | `bool` | `true` | Per-event-type metrics |
| `EnablePerHandler` | `bool` | `true` | Per-handler metrics |