Callback (or equivalent) when container w/ Rails app finishes booting?

Question

I have a docker container containing a rails app. Running the container starts a script similar to this: https://github.com/defunkt/unicorn/blob/master/examples/init.sh, which does some busy work and then reaches out to a unicorn.rb script similar to this: https://github.com/defunkt/unicorn/blob/master/examples/unicorn.conf.rb.

I have a clojure web app that can tell this container to run. The request to do this is nonblocking, and the user of the site will somehow be notified when the rails app is ready to receive requests.

I can think of various hacky ways to do this, but is there an idiomatic way to have the container let me know when the unicorn rails app is ready to receive web requests?.

I'd like to have it hit some callback url in my app but I'm open to other options. Thanks!

Answer 1

I don't get why you need to do it that way. Couldn't you just perform HTTP requests to the rails part (eg http:://my_page.com/status) and handle the response accordingly?