Register a producer

Register(ctx context.Context, cfg *ProducerConfig) (*ProducerInstance[T], error)

Creates a producer instance for an existing stream. Each call creates an independent instance and automatic batch queue. Producer settings live in the process and are not stored as a registration row.

Example

Use an initialized client, the registered payments.requested stream, and the example payload.

payments := client.Stream[PaymentRequestedV1]("payments.requested")
producer, err := payments.Producer().Register(ctx, nil)
if err != nil {
  return err
}
result, err := producer.Produce(ctx, &PaymentRequestedV1{OrderId: "order-123"}, nil)
if err != nil {
  return err
}
fmt.Println(result.Id, result.Duplicate)

Parameters

Parameter	Type	Required	Description
`ctx`	`context.Context`	Yes	Cancellation or its deadline interrupts registration’s database reads. Later produce calls use their own contexts.
`cfg`	`*ProducerConfig`	No	`nil` uses defaults. `Register` fills defaults and retains the supplied configuration. Do not mutate it while the instance is in use.

ProducerConfig

Field	Type	Default	Description
`Message`	`*MessageOptions`	`nil`	Producer defaults for fields left unset by a produce call. Fields unset in both remain unset for the consumer to resolve.
`Batch`	`BatcherConfig`	Nested defaults	Automatic batching for concurrent `Produce` calls on this instance.
`SlowProduceThreshold`	`time.Duration`	`0`	Calls exceeding a positive threshold emit `SQL0038` with their duration. Zero disables warnings. Must be nonnegative.

BatcherConfig

Field	Type	Default	Description
`MaxSize`	`int`	`100`	Maximum messages in an automatic batch. Must be at least `1`.
`ConcurrencyLimit`	`int`	`4`	Maximum automatic batch transactions this instance can run concurrently. Each transaction needs a pool connection. Must be at least `1`.
`AttemptTimeout`	`time.Duration`	`10s`	Time allowed for one batch transaction attempt. Also applies to `ProduceBatch`. Must be positive.
`ShutdownGrace`	`time.Duration`	`15s`	How long a cancelled `Produce` call already in the batch queue waits for its outcome. A positive value must exceed `AttemptTimeout`. A negative value abandons the wait immediately.

Zero selects the default for every Batch field. Automatic batching applies to Produce calls without a caller-supplied idempotency key. ProduceBatch, ProduceFunc, ProduceInTx, and ProduceFuncInTx do not share this queue.

Returns

Condition	Return value
Registration succeeds	`(producer, nil)`, where `producer` is a `*ProducerInstance[T]`.
Registration fails	`(nil, err)`.

The instance resolves the stream id at registration. Reuse it across produce calls to share its batch queue.

Errors

Error	When
Validation error	The stream name is empty or configuration is invalid.
`ErrStreamNotFound`	The stream has not been registered.
Schema compatibility error	The system or stream schema is incompatible with this build.
Database or context error	Registration reads fail or are interrupted.

Register a stream — Create the producer’s target stream.
Message options — Requested processing options and consumer bounds.