Change a Rails application to production

Question

This would now be

rails server -e production

Or, more compact

rails s -e production

It works for rails 3+ projects.

How to setup and run a Rails 4 app in Production mode (step-by-step) using Apache and Phusion Passenger:

Normally you would be able to enter your Rails project, rails s, and get a development version of your app at http://something.com:3000. Production mode is a little trickier to configure.

I've been messing around with this for a while, so I figured I'd write this up for the newbies (such as myself). There are a few little tweaks which are spread throughout the internet and figured this might be easier.

1. Refer to this guide for core setup of the server (CentOS 6, but it should apply to nearly all Linux flavors): https://www.digitalocean.com/community/tutorials/how-to-setup-a-rails-4-app-with-apache-and-passenger-on-centos-6

2. Make absolute certain that after Passenger is set up you've edited the /etc/httpd/conf/httpd.conf file to reflect your directory structure. You want to point DocumentRoot to your Rails project /public folder Anywhere in the httpd.conf file that has this sort of dir: /var/www/html/your_application/public needs to be updated or everything will get very frustrating. I cannot stress this enough.

3. Reboot the server (or Apache at the very least - service httpd restart )

4. Enter your Rails project folder /var/www/html/your_application and start the migration with rake db:migrate. Make certain that a database table exists, even if you plan on adding tables later (this is also part of step 1).

5. RAILS_ENV=production rake secret - this will create a secret_key that you can add to config/secrets.yml . You can copy/paste this into config/secrets.yml for the sake of getting things running, although I'd recommend you don't do this. Personally, I do this step to make sure everything else is working, then change it back and source it later.

6. RAILS_ENV=production rake db:migrate

7. RAILS_ENV=production rake assets:precompile if you are serving static assets. This will push js, css, image files into the /public folder.

8. RAILS_ENV=production rails s

At this point your app should be available at http://something.com/whatever instead of :3000. If not, passenger-memory-stats and see if there an entry like 908 469.7 MB 90.9 MB Passenger RackApp: /var/www/html/projectname

I've probably missed something heinous, but this has worked for me in the past.

If you're running on Passenger, then the default is to run in production, in your apache conf:

<VirtualHost *:80>
  ServerName application_name.rails.local
  DocumentRoot "/Users/rails/application_name/public"
  RailsEnv production ## This is the default
</VirtualHost>

If you're just running a local server with mongrel or webrick, you can do:

./script/server -e production

or in bash:

RAILS_ENV=production ./script/server

actually overriding the RAILS_ENV constant in the enviornment.rb should probably be your last resort, as it's probably not going to stay set (see another answer I gave on that)

If mipadi's suggestion doesn't work, add this to config/environment.rb

# force Rails into production mode when                          
# you don't control web/app server and can't set it the proper way                  
ENV['RAILS_ENV'] ||= 'production'

Change the environment variable RAILS_ENV to production.

$> export RAILS_ENV=production