CODEWITHSUNDEEP
heroku
drmrbrewer
drmrbrewer

Reputation: 12989

heroku: scaling dynos from node app

Using the heroku CLI it is possible to scale dynos like so:

$ heroku ps:scale web=1

But I'd like to be able to scale dynos from within my node app (running on heroku, so I can't just exec the above command because the CLI isn't available), e.g. to respond dynamically to changes in load.

I am vaguely familiar with the heroku client package, but can't see how it could be used for dyno scaling.

Upvotes: 2

Views: 220

Answers (1)

drmrbrewer
drmrbrewer

Reputation: 12989

So curiousity got the better of me, and I seem to have worked out an answer to my own question...

The key is to use the Heroku API, which is accessed in the node app using the heroku-client package mentioned in my question.

The Heroku API has a Formation Update interface, which allows you to set the scale (or quantity) of the web dynos.

The following example scales the web dyno to 2:

var Heroku = require('heroku-client');
var heroku = new Heroku({ token: process.env.HEROKU_API_TOKEN });

heroku.patch('/apps/yourappname/formation/web', { body: {"quantity": 2} }).then(response => {
    console.log('patch response: ' + JSON.stringify(response));
});

... where yourappname is of course your app's name.

Upvotes: 3

Related Questions