AWS OpsWorks Environment variables not working

Question

I am running Ubuntu 14.04 LTS 64 bit Rails Application and I am unable to access my App environment variables.

In OpsWorks App panel, I set my environment variables, say:

MYKEY: 1234

Then I save and deploy my app again to make these visible.

In my Rails app, or the rails console I get nil:

$ bundle exec rails c production
>ENV["MYKEY"]
=> nil

I have tried restarting the server. I'm not sure what I am missing, I have been using environment variables in other services.

How can I trace where these should be set?

Answer 1

AWS OpsWorks console lets you declare environment variables but to let them be available for our Rails app we need to use a Chef cookbook recipe plus some precautions.

In a nutshell we use the config/secrets.yml file combined with config/application.yml file, Figaro gem and a Chef cookbook recipe. The chef cookbook recipe read the variables defined in OpsWorks console and let them available to Rails app writing the config/application.yml file.

I have published a detailed guide to explain how exactly do it. Link here.

These are the core points that I covered:

1. Use config/secrets.yml file (added from Rails 4.1)
2. Use Figaro gem to load variables in the environment
3. Declare environment variables inside AWS OpsWorks Console
4. Use a custom Chef recipe to create a config/application.yml file that Figaro will use to let variables available

Answer 2

OpsWorks stores environmental variables in different places depending on what kind of app you're deploying. On Rails / Passenger they should be saved in the Apache config file #{your_app_name}.conf. (Source)

This means they aren't available in your normal shell environment.

I know the Node.js recipes stored everything in an /srv/www/#{app_name}/shared/app.env file... which is then sourced to pull in the environment to run the Node server. This implementation detail also meant you could write shell scripts that sourced that app.env file, then called some Node script or whatever.

Of course, Rails isn't Node. I have no idea if the environmental variables are also stored somewhere else or not: a quick look at the Rails recipes in the OpsWorks cookbooks didn't find anything obvious, but maybe I missed something.

Depending on the amount of modifications you have going on in your OpsWorks cookbook, you could create a deploy recipe that does something like this:

application_environment_file do user deploy[:user] group deploy[:group] path ::File.join(deploy[:deploy_to], "shared") environment_variables deploy[:environment_variables] end

(maybe adjusting the path)

Then to run your console, when you're SSHed into the server, do something like

sudo source /srv/www/my_app_name/shared/app.env; bundle exec rails console -e production or whatever.

Answer 3

I (with some help from Bruno at the AWS PopUp Loft in NYC) added some custom Chef code inside the after_restart.rb deploy hook, simply add the folder "deploy" to your apps root directory and inside add "after_restart.eb." In it ....

Chef::Log.info("Running deploy/after_restart.rb")

contents = []

node[:deploy].each do |application, deploy|
  deploy[:environment_variables].each do |key, value|
    contents << "export #{key}=\"'#{value}'\""
  end
end


Chef::Log.info("Adding the environment variables to /etc/profile.d/startup_env_config.sh")

bash "create_startup_env_config.sh" do
  user "root"
  cwd  "/etc/profile.d"
  code <<-EOH
    echo \''#{contents.join(" ")}\'' > startup_env_config.sh
    source startup_env_config.sh
    cd #{release_path}

    EOH
  end

And that's it. If you update the environment variables inside the OpsWorks panel remember to restart your instances.