How to have a Play framework app autostart during boot on Elastic Beanstalk CentOS ec2 instances

So you’ve created an Elastic Beanstalk environment, you have a play framework distribution which you’ve created using play dist (either on your local environment, or right there on the server, whatever you prefer)

play dist outputs a my-app-1.0.zip file which has a self-contained version of your app with all the necessary libraries and a start script.

Afer you unzip it, you end up with a my-app-1.0/lib/ folder and a start script.

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Make sure it’s executable by using chmod +x start on the start script.

So now, this is all in the first ec2 instance of your elastic beanstalk environment, if you’re like me and you’ve used ubuntu/debian for your server management things can be slightly different here, since Amazon preferred CentOS for their default image, and here I’ll show you how to make your play app auto start when the server boots because you want every new machine that may be instanciated to have your app installed and to start the service as soon as the machine is up.

Create a /etc/init.d/myappd script
(I’m using ‘myapp’ here as an example, your app can be named whatever is named, so replace accordingly)

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Wire it to autostart

The simplest way I found to have this script start when the server would boot was to add it at the end of the
/etc/rc.local file. (In ubuntu you’d register the new script with the upate-rc.d command)

[pastacode lang=”bash” manual=”%23!%2Fbin%2Fsh%0A%23%0AThis%20script%20will%20be%20executed%20after%20all%20the%20other%20init%20scripts.%0AYou%20can%20put%20your%20own%20initialization%20stuff%20in%20here%20if%20you%20don%E2%80%99t%0Awant%20to%20do%20the%20full%20Sys%20V%20style%20init%20stuff.%0A%0Atouch%20%2Fvar%2Flock%2Fsubsys%2Flocal%0A%0A%2Fetc%2Finit.d%2Fmyappd%20start” message=”” highlight=”” provider=”manual”/]