Relay uses functional options for wiring dependencies and a Config struct for tuning runtime behavior.
Functional options01
The Relay struct is configured with functional options passed to relay.New():
r, err := relay.New(
relay.WithStore(postgresStore),
relay.WithLogger(slog.Default()),
relay.WithConcurrency(20),
relay.WithPollInterval(2 * time.Second),
relay.WithBatchSize(100),
relay.WithRequestTimeout(15 * time.Second),
relay.WithMaxRetries(8),
relay.WithRetrySchedule(customSchedule),
relay.WithShutdownTimeout(60 * time.Second),
relay.WithCacheTTL(time.Minute),
)Available options
| Option | Purpose | Default |
WithStore(s) | Set the persistence backend (required) | -- |
WithLogger(l) | Set the structured logger | slog.Default() |
WithConcurrency(n) | Number of delivery worker goroutines | 10 |
WithPollInterval(d) | How often the engine checks for pending deliveries | 1s |
WithBatchSize(n) | Max deliveries dequeued per poll cycle | 50 |
WithRequestTimeout(d) | HTTP timeout per delivery attempt | 30s |
WithMaxRetries(n) | Maximum delivery attempts before DLQ | 5 |
WithRetrySchedule(s) | Backoff intervals between retries | [5s, 30s, 2m, 15m, 2h] |
WithShutdownTimeout(d) | Max wait for in-flight deliveries on shutdown | 30s |
WithCacheTTL(d) | TTL for the catalog's in-memory cache (0 = no cache) | 30s |
Config struct02
type Config struct {
Concurrency int
PollInterval time.Duration
BatchSize int
RequestTimeout time.Duration
MaxRetries int
RetrySchedule []time.Duration
ShutdownTimeout time.Duration
CacheTTL time.Duration
}Default retry schedule03
var DefaultRetrySchedule = []time.Duration{
5 * time.Second,
30 * time.Second,
2 * time.Minute,
15 * time.Minute,
2 * time.Hour,
}After all retries are exhausted, the delivery moves to the DLQ.
Required options04
The only required option is WithStore(). Without a store, relay.New() returns ErrNoStore.