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Kafka

Kafka is currently supported through the following generators (channels):

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TypeScript✅✅

All of this is available through AsyncAPI. If you use

Channels​

Read more about the channels generator here before continuing.

This generator provides support functions for each resource ensuring you the right payload and parameter are used.

Input (AsyncAPI)Using the code
asyncapi: 3.0.0
info:
  title: Account Service
  version: 1.0.0
  description: This service is in charge of processing user signups
channels:
  userSignups:
    address: user/signedup
    messages:
      userSignedup:
        $ref: '#/components/messages/UserSignedUp'
operations:
  publishUserSignups:
    action: send
    channel:
      $ref: '#/channels/userSignups'
  consumeUserSignups:
    action: receive
    channel:
      $ref: '#/channels/userSignups'
components:
  messages:
    UserSignedUp:
      payload:
        type: object
        properties:
          displayName:
            type: string
            description: Name of the user
          email:
            type: string
            format: email
            description: Email of the user

import { Kafka } from 'kafkajs';
// Location depends on the payload generator configurations
import { UserSignedup } from './__gen__/payloads/UserSignedup';
// Location depends on the channel generator configurations
import { Protocols } from './__gen__/channels';
const { kafka } = Protocols;
const { consumeFromConsumeUserSignups, produceToPublishUserSignups } = kafka;

/**
 * Setup the regular client
 */
const kafkaClient = new Kafka({
  clientId: 'test',
  brokers: ['localhost:9093'],
});

const myPayload = new UserSignedup({displayName: 'test', email: 'test@test.dk'});

// Consume the messages with the generated channel function
const consumerCallback = async (
    err,
    msg: UserSignedUp | undefined, 
    parameters: UserSignedUpParameters | undefined, 
    kafkaMsg: EachMessagePayload | undefined
  ) => {
  // Do stuff once you consumer from the topic
};
const consumer = await consumeFromConsumeUserSignups(
  consumerCallback,
  myParameters, 
  kafkaClient, 
  {
    fromBeginning: true, 
    groupId: 'testId1'
  }
);

// Produce the messages with the generated channel function
const producer = await produceToPublishUserSignups(myPayload, kafkaClient);