note►howto

How to test nsq with docker (and nsqjs)

Preparations

  1. Find out docker host’s IP and create the following shell function. Replace 172.17.0.1 with the one found on your system:
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export DOCKER_HOST=172.17.0.1
runnsq() {
  host=$DOCKER_HOST
  docker run --rm --name lookupd -p 4160:4160 -p 4161:4161 -d nsqio/nsq /nsqlookupd
  docker run --rm --name nsqd -p 4150:4150 -p 4151:4151 -d nsqio/nsq /nsqd \
      --broadcast-address=$host --lookupd-tcp-address=$host:4160
  docker run --rm --name nsqadmin -p 4171:4171 -d nsqio/nsq /nsqadmin \
      --lookupd-http-address=$host:4161
}

  1. Get nsq
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    docker pull nsqio/nsq

Start the containers

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run-nsq

Publish a message **

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curl -d 'hello world' "http://$DOCKER_HOST:4151/pub?topic=sample_topic"

Set up a consumer

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mkdir -p ~/projects/test-nsq
cd $_
npm i nsqjs

Create consumer.js as listed below. 

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// consumer.js
const nsq = require('nsqjs')

const reader = new nsq.Reader('sample_topic', 'test_channel', {
  lookupdHTTPAddresses: `${process.env.DOCKER_HOST}:4161`
})

reader.connect()

console.log('started')
reader.on('message', msg => {
  console.log('Received message [%s]: %s', msg.id, msg.body.toString())
  msg.finish()
})

Test

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node consumer.js

You should see something similar to:

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Received message [0abc62e587053000]: hello world

nsqadmin

Open http://127.0.0.1:4171/ from a browser.

** The reason why publisher runs before consumer is for the topic to be created before a consumer can subscribe to it.