A Kubeless Trigger represents an event source the functions can be associated with it. When an event occurs in the event source, Kubeless will ensure that the associated functions are invoked. HTTP-trigger addon to Kubeless adds support for HTTP based invocation of Kubeless functions. A NATS queue topic can be associated with one or more Kubeless functions. Kubeless functions associated with a topic are triggerd as and when messages get pubslished to the topic.
Please refer to the documentation on how to use HTTP trigger with Kubeless.