simple in-process job dispatcher
npm install simple-job-dispatcherCurent Version 0.0.3
simple-job-dispatcher is a simple in-process job dispatcher. This is probably
useful only if the job you going to do is async, as all jobs are still executed
in single event-loop. If you job is synchronus, it might be easier just to use a
simple loop.
- node.js -- v10.16.0 or newer, older version probably
works but only tested on 10.16
npm install simple-job-dispatcher
There is an exmaple.js provided, which also shown below.
const dispatcher_factory = require('simple-job-dispatcher');
const dispatcher = new dispatcher_factory();
// define a worker function that process job
// in this case it just display job detail and return after 5s
const worker = (job, done) => {
console.log(received job: ${JSON.stringify(job)});
setTimeout(done, 5000);
};
// initialize dispatcher with max parallel processing of 2 jobs
dispatcher.init(
2,
worker
);
// use getStats to check dispatcher status
setInterval(() => {
console.log(dispatcher.getStats());
}, 1000);
// exit the app after 11s
setTimeout(process.exit, 11000, 0);
// push some jobs
dispatcher.addJob({
id: 1,
data: "something"
}, () => console.log('job done'));
dispatcher.addJob({
id: 2,
data: "something"
}, () => console.log('job done'));
dispatcher.addJob({
id: 3,
data: "something"
}, () => console.log('job done'));
dispatcher.addJob({
id: 4,
data: "something"
}, () => console.log('job done'));
Running it shall give you result like below
% node example.js
received job: {"id":1,"data":"something"}
received job: {"id":2,"data":"something"}
{ queue_count: 2, loading: 2 }
{ queue_count: 2, loading: 2 }
{ queue_count: 2, loading: 2 }
{ queue_count: 2, loading: 2 }
job done
received job: {"id":3,"data":"something"}
job done
received job: {"id":4,"data":"something"}
{ queue_count: 0, loading: 2 }
{ queue_count: 0, loading: 2 }
{ queue_count: 0, loading: 2 }
{ queue_count: 0, loading: 2 }
{ queue_count: 0, loading: 2 }
job done
job done
{ queue_count: 0, loading: 0 }