Why?

We have several demo/example/tutorial Apps deployed to Heroku. Apps on the “free” tier go to sleep after 30 minutes of inactivity. see: https://devcenter.heroku.com/articles/free-dyno-hours

In order to wake them, we wrote a few lines of code that can be added to any Elixir/Phoenix App and invoked as an image in the README.md of the project that links to the App.

We had implemented the “wake from sleep” endpoint several times in our Heroku Apps, most recently in our email app. After copy-pasting the code a couple of times, we decided to make it a DRY reusable package that we can use in our next app(s)!

What?

An easy way for us to wake our Heroku demo apps.

Note: our use case for this module is “just in time” waking of Heroku dynos. <br /> If you need your “Free” Heroku app to be always awake or awake during specific times of day, consider combining the ping package with a CRON job. You can use a free service such as: https://cron-job.org as described by Mahdhi Rezvi in: https://medium.com/better-programming/keeping-my-heroku-app-alive-b19f3a8c3a82

Who?

This package is for anyone building an Elixir/Phoenix app deployed to Heroku.

How?

1. Installation

Install by adding ping to your list of dependencies in mix.exs:

def deps do
  [
    {:ping, "~> 1.0.0"}
  ]
end

2. Create a get /ping Route in your router.ex

3. Create the ping/2 Function in your Controller

You can either create a brand new controller, or use an existing one if you prefer.

4. Add a GIF to the README.md of the Heroku App

Documentation available at https://hexdocs.pm/ping. But there’s really not much to it.