Channels

export default {
  ...,
  generators: [
    {
      preset: 'channels',
      outputPath: './src/__gen__/', 
      language: 'typescript',
      protocols: ['nats']
    }
  ]
};

channels preset with asyncapi input generates support functions for each operation based on the selected protocol.

This generator uses payloads and parameters generators, in case you dont have any defined, it will automatically include them with default values.

This is supported through the following inputs: asyncapi

It supports the following languages; typescript

It supports the following protocols; nats, kafka, mqtt, amqp, event_source

Options

These are the available options for the channels generator;

Option	Default	Type	Description
asyncapiReverseOperations	`false`	Boolean	Used in conjunction with AsyncAPI input, and reverses the operation actions i.e. send becomes receive and receive becomes send. Often used in testing scenarios to act as the reverse API.
asyncapiGenerateForOperations	`true`	Boolean	Used in conjunction with AsyncAPI input, which if `true` generate the functions upholding how operations are defined. If `false` the functions are generated regardless of what operations define. I.e. `send` and `receive` does not matter.
functionTypeMapping	`{}`	Record<String, ChannelFunctionTypes[]>	Used in conjunction with AsyncAPI input, can define channel ID along side the type of functions that should be rendered.
kafkaTopicSeparator	`'.'`	String	Used with AsyncAPI to ensure the right character separate topics, example if address is my/resource/path it will be converted to my.resource.path
eventSourceDependency	`'@microsoft/fetch-event-source'`	String	Because @microsoft/fetch-event-source is out-dated in some areas we allow you to change the fork/variant that can be used instead

TypeScript

Depending on which protocol, these are the dependencies:

NATS: https://github.com/nats-io/nats.js v2
Kafka: https://github.com/tulios/kafkajs v2
MQTT: https://github.com/mqttjs/MQTT.js v5
AMQP: https://github.com/amqp-node/amqplib v0
EventSource: event_source_fetch: https://github.com/Azure/fetch-event-source v2, event_source_express: https://github.com/expressjs/express v4

For TypeScript what is generated is a single file that include functions to help easier interact with AsyncAPI channels. For example;

import { Protocols } from 'src/__gen__/index';
const { nats, kafka, mqtt, amqp, event_source, ... } = Protocols;
const { jetStreamPublishTo..., jetStreamPullSubscribeTo..., jetStreamPushSubscriptionFrom..., publishTo..., subscribeTo... } = nats;

First we import the generated file, which is located based on your outputPath in the generator options.

Next we import the desired protocol and then we have access to all the support functions. These support functions are an easy way to interact with channels defined in your AsyncAPI document. Take notice it does not care which operations you have defined.

Options​

TypeScript​

Options

TypeScript