connections

type Connection interface {
	Raw() interface{}
	CreateSubscription(ctx context.Context, opts *SubscriptionOptions) (Queue, error)
	CreateTopic(ctx context.Context, opts *TopicOptions) (Topic, error)
	DeleteSubscription(ctx context.Context, opts *SubscriptionOptions) error
}

type Queue interface {

	// ReceiveMessages pulls messages from the nats queue server.
	// If no messages are currently available, this method should block for
	// no more than about 1 second. It can return an empty
	// slice of messages and no error. ReceiveBatch will be called again
	// immediately, so implementations should try to wait for messages for some
	// non-zero amount of time before returning zero messages. If the underlying
	// service doesn't support waiting, then a time.Sleep can be used.
	ReceiveMessages(ctx context.Context, batchCount int) ([]*driver.Message, error)
	Unsubscribe() error
	Ack(ctx context.Context, ids []driver.AckID) error
	Nack(ctx context.Context, ids []driver.AckID) error
	IsQueueGroup() bool
}

type SubscriptionOptions struct {
	StreamName        string
	StreamDescription string

	Subjects []string
	Durable  string

	ConsumerName string

	ConsumersMaxCount            int
	ConsumerRequestBatch         int
	ConsumerRequestMaxBatchBytes int
	ConsumerRequestTimeoutMs     int
	ConsumerAckWaitTimeoutMs     int

	//The maximum number of fetch requests that are all waiting in parallel to receive messages.
	//This prevents building up too many requests that the server will have to distribute to for a given consumer.
	ConsumerMaxWaiting          int
	ConsumerMaxRequestExpiresMs int

	ConsumerMaxAckPending int
}

type Topic interface {
	Subject() string
	PublishMessage(ctx context.Context, msg *nats.Msg) (string, error)
}

type TopicOptions struct {
	Subject string
}