Peter Marklund's Home

Murphy teaches us that if something can go wrong it will. Given all the differences there are between my development and production server - operating system, web server, database, gems etc. - I can't really feel comfortable deploying my application unless I have first run my test suite not only in development but also in production. Thanks to the beautiful and powerful API of Capistrano this is a walk in the park to accomplish:

desc "Run the full tests on the deployed app." 
task :run_tests do
 run "cd #{release_path} && RAILS_ENV=production rake && cat /dev/null > log/test.log" 
end

desc "Copy in server specific configuration files"
task :copy_shared do
  run <<-CMD
    cp #{shared_path}/system/voxway.rb #{release_path}/config &&
    cp #{shared_path}/system/database.yml #{release_path}/config
  CMD
end

desc "Run pre-symlink tasks" 
task :before_symlink, :roles => :web do
  copy_shared
  run_tests
end

In my current project I am deploying to two identical Linux servers and since Capistrano runs the tests in parallel on those servers I need to keep two distinct test databases in production - one for each server. Credit for this approach goes to Evan Henshaw-Plath who described it nicely.