Use Kue in Node.js
2019, Jan 09
First, start a redis server locally
The easiest way start the redis instance is using Docker, just one command
$ docker run --name some-redis -p 6379:6379 -d redis
Install Kue in Node.js project
npm install kue
See more details at GitHub page: https://github.com/Automattic/kue
Build a queue.js with Kue
queue.js
'use strict';
import kue from 'kue';
const queue = kue.createQueue();
const TOPIC = 'LOG';
const push = (log, callback) => {
const job = queue.create(TOPIC, {
log: log
})
job.save(callback);
};
const process = (func) => {
queue.process(TOPIC, 1, async (job, done) => {
await func(job.data.log);
done();
});
};
module.exports = { push, process };
use queue.js
// push
queue.push(log, err => {
if (err) {
console.log(err.stack);
}
console.log('pushed.');
})
// process
queue.process(async log => {
// process the log
});
Unit testing
Here is the unit test for queue.js with Jest: queue.test.js
'use strict';
const kue = require('kue');
const queue = kue.createQueue();
import risQueue from '../src/queue';
beforeAll(() => {
queue.testMode.enter(true);
});
afterEach(() => {
queue.testMode.clear();
});
afterAll(async () => {
let queue = kue.createQueue();
queue.testMode.exit();
queue.shutdown(1, null);
});
test('enqueue records', async () => {
const mockPushCallback = jest.fn();
const mockProcessCallback = jest.fn();
risQueue.process(mockProcessCallback);
risQueue.push({ foo: 'bar' }, mockPushCallback);
risQueue.push({ foo: 'bar' }, mockPushCallback);
await new Promise((resolve, reject) => {
setTimeout(() => {
resolve();
}, 300);
});
expect(mockPushCallback.mock.calls.length).toBe(2);
expect(mockProcessCallback.mock.calls.length).toBe(2);
expect(queue.testMode.jobs.length).toBe(2);
});
Run the test
- Call
jestto run the unittest. - Call
jest -u --coverageto run the unittest with a report about the code coverage.
Important:
- While running the unittest, you must make sure the redis server is running on the test system.
- Make sure call the
queue.shutdown(1, null);at theafterAll()function.