How to automatically launch browser when rails server starts?

Question

Is there a way of automatically launching your browser and pointing it to http://localhost:3000 when you run rails server?

And secondly ensuring this only happens in development?

I would have thought that Launchy would have done the trick, but I'm struggling to work out where to put it.

I've tried adding an initialiser config/initializers/launchy.rb

require 'launchy'
Launchy.open("http://localhost:3000")

And this triggers the browser to open, create a new tab and visit http://localhost:3000 as expected, however it runs before the server / application has finished booting and I get a Cannot connect to Server error in the browser.

If I reload in the browser my app works just fine so I'm confident it's not a problem with my app, rather the timing of the Launch.open call.

I tried renaming launchy.rb to z_launchy.rb so it gets loaded last as per the docs but still the same problem. Launchy fires before the Application is ready for it.

I've also tried adding the code to config/puma.rb (I'm using puma as my server), to config/enviroments/developoment.rb but always the same problem. The Launchy.open command gets called to soon.

Where should I call Launchy.open("http://localhost:3000") to ensure that a) It runs after the application has loaded and is ready to receive requests; and b) So it only runs in development, not in test or production?

System set up OS X 10.11.3, Rails 4.2.5, ruby 2.2.1p85, puma version 2.15.3

Answer 1

Putting it into config.ru would work, after the run Rails.application line. By the time that returns, your app is ready to go. To run it only in development, check the Rails.env.

require ::File.expand_path('../config/environment', __FILE__)
run Rails.application
Launchy.open("http://localhost:3000") if Rails.env.development?

This is easy, but it feels dirty to me to have this sitting in your app. Better would be a small script that starts your server, waits a moment, then launches the browser.