Connectum API Reference / @connectum/events / assertPublishTopic

Function: assertPublishTopic()

assertPublishTopic(options): void

Defined in: packages/events/src/subscriptionPatterns.ts:91

Reject a topic the adapter's broker cannot serve, before the adapter publishes anything.

The publishing twin of assertSubscriptionPatterns, with the same two rules. Adapters call it at the start of publish(): without it NATS answers a malformed subject with jetstream is not enabled, Kafka answers its reserved names with an error that does not name the topic, and the in-memory adapter delivers the event to wildcard subscribers although no subscription pattern could ever name that topic. Adapters whose broker accepts any key (Redis, RabbitMQ) do not call it.

Parameters

options

adapter

string

The adapter name used in the message

rule?

SubscriptionPatternRule

What to refuse; "no-empty-segment" when omitted

topic

string

The topic the event is published to

Returns

void

Throws

When the topic is refused; the message names the adapter and the topic.

Example

assertPublishTopic({ adapter: "MyAdapter", topic: "user.created" }); // returns
assertPublishTopic({ adapter: "MyAdapter", topic: "user..created" }); // throws TypeError
assertPublishTopic({ adapter: "MyAdapter", topic: "user..created", rule: "kafka-topic-name" }); // returns