ErrNoError on TopicCreate

[maciej]

The call to CreateTopics using sarama.Broker returns a TopicErrors map containing errors on topic creation. However it does also return a quite peculiar error:

go
const (
	ErrNoError                            KError = 0
// ...
)

Why was the API designed this way? It seems not to be idiomatic Go.

[dnwe]

@maciej 👋🏻 thanks for getting in touch

Those 'KError' codes map to the return codes that the Kafka protocol returns.

So CreateTopics on sarama.Broker (although an exported name) isn't really intended for Sarama users, but is roundtripping the CreateTopics protocol message to Kafka and receiving the response in a CreateTopicsResponse struct

sarama/broker.go

Lines 629 to 638 in c067a7f

	func (b *Broker) CreateTopics(request *CreateTopicsRequest) (*CreateTopicsResponse, error) {
	response := new(CreateTopicsResponse)
	err := b.sendAndReceive(request, response)
	if err != nil {
	return nil, err
	}
	return response, nil
	}

Typically a Sarama user would be creating topics through the Admin client interface, which should return more idiomatic Go types and expose less of the internals of the client (although we have a backlog item to improve that separation in /v2 of Sarama

sarama/admin.go

Line 223 in c067a7f

func (ca *clusterAdmin) CreateTopic(topic string, detail *TopicDetail, validateOnly bool) error {

[maciej]

Thanks for getting back to me quickly on that @dnwe ! I have missed ClusterAdmin when browsing the library interfaces. Thanks for pointing me to it.

With my question answered I'm considering the discussion closed.

[dnwe]

No worries at all, feel free to post any questions you have as these are always handy to help buildup a FAQ that others users can find in the future