README.md

graphql-kafka-subscriptions

It implements the PubSubEngine Interface from the graphql-subscriptions package and also the new AsyncIterator interface. It allows you to connect your subscriptions manager to a single Kafka topic used as Pub/Sub communication channel.

Installation

npm install graphql-kafka-subscriptions

Mac OS High Sierra / Mojave

OpenSSL has been upgraded in High Sierra and homebrew does not overwrite default system libraries. That means when building node-rdkafka, because you are using openssl, you need to tell the linker where to find it:

export CPPFLAGS=-I/usr/local/opt/openssl/include
export LDFLAGS=-L/usr/local/opt/openssl/lib

Then you can run npm install on your application to get it to build correctly.

Usage

Initializing the kafka pubsub client

import { KafkaPubSub } from 'graphql-kafka-subscriptions'

export const pubsub = new KafkaPubSub({
  topic: 'name-of-the-topic',
  host: 'INSERT_KAFKA_IP',
  port: 'INSERT_KAFKA_PORT',
  globalConfig: {} // options passed directly to the consumer and producer
})

Publishing messages to the subcrition

payload = {
  firstName: "John",
  lastName: "Doe"
}

pubsub.publish('pubSubChannel', payload);

Subscribing to a channel

const onMessage = (payload) => {
  console.log(payload);
}

const subscription = await pubsub.subscribe('pubSubChannel', onMessage)

Contributing

Contributions are welcome. Make sure to check the existing issues (including the closed ones) before requesting a feature, reporting a bug or opening a pull requests.

For sending a PR follow:

1. Fork it (https://github.com/ancashoria/graphql-kafka-subscriptions/fork)
2. Create your feature branch (git checkout -b my-new-feature)
3. Commit your changes (git commit -am 'Add some feature')
4. Push to the branch (git push origin my-new-feature)
5. Create a new Pull Request

Horia Miron notes:

Thanks to davidyaha for graphql-redis-subscriptions which was the main inspiration point for this project.