Easy Deploys to Multiple Environments with Capistrano

At Viddler, we’re switching to using Git and Capistrano for our internal projects, and I was tasked with setting up the system to deploy our code to both staging and production environments. Capistrano doesn’t have built-in environment switching, but it’s dead simple to add it yourself.

The key to getting this to work is to utilize Capistrano’s ability to chain tasks–if you run cap task1 task2, it will run the two commands in the order you listed them. Variables are shared between the tasks, so if you set a variable in task1, task2 will be able to access it. To get multiple environments working, you just create tasks to set environment variables, which you call before the actual task you want to run.

The first step is to figure out which variables you need to change, and then move them into their own tasks. Here’s an example of the tasks we added:

desc "Run on staging server"
task :staging do
  server "staging.myserver.com", :app, :web, :db, :primary => true
end

desc "Run on production server"
task :production do
  server "myserver.com", :app, :web, :db, :primary => true
end

Now, if you want to deploy to staging, just run cap staging deploy, and for production run cap production deploy. Easy.

Posted on December 10, 2009 • Leave a Comment
Tagged with: Capistrano, Viddler, Tips, Development, Code