Professional Ruby on Rails™

Chapter 12. Deploying Your Application

It's inevitable. At some point your Rails application has to leave the comforting home of your development setting and make its own way in the cold, cruel world of production environments. Deploying Rails applications has been an area of extremely rapid change and development — even by Rails standards — with the definition of deployment best-practice tools changing completely every few months. As I write this, though, the field appears to have settled on a consistent set of tools. This toolset is designed to take you from your development environment to low-traffic, high-traffic, and very-high–traffic production sites using the same basic technologies.

Every deployment is different, of course, and the requirements for deploying high-traffic Rails sites like Basecamp or Twitter are different than you might need for an internal sales tool, or for a soup-recipe trading site. This chapter focuses on two of the most generally valuable tools in the Rails deployment kit: Capistrano, which is used to automate deployment activities, and Mongrel, which has emerged as the Rails application server of choice.

Deployment can be complex, and one of the best ways to mitigate that complexity is to start practicing the deployment early and often. Even during the earliest part of development, you should try to set up a staging server and start deploying to it, to test out all the various connections between the web server, source control, the database, and ...