Mina provides the
deploy command which queues up a deploy script for you.
# config/deploy.rb set :domain, 'flipstack.com' set :user, 'flipstack' set :deploy_to, '/var/www/flipstack.com' set :repository, 'http://github.com/flipstack/flipstack.git' task :deploy do deploy do # Put things that prepare the empty release folder here. # Commands queued here will be ran on a new release directory. invoke :'git:clone' invoke :'bundle:install' # These are instructions to start the app after it's been prepared. to :launch do queue 'touch tmp/restart.txt' end # This optional block defines how a broken release should be cleaned up. to :clean do queue 'log "failed deployment"' end end end
It works by capturing the queued commands inside the block, wrapping them in a deploy script, then queueing them back in.
How deploying works
Here is an example of a deploy! (Note that some commands have been simplified to illustrate the point better.)
Step 1: Build it
The deploy process builds a new temp folder with instructions you provide. In this example, it will do
$ mina deploy --verbose -----> Creating the build path $ mkdir tmp/build-128293482394 -----> Cloning the Git repository $ git clone https://github.com/flipstack/flipstack.git . -n --recursive Cloning... done. -----> Installing gem dependencies using Bundler $ bundle install --without development:test Using i18n (0.6.0) Using multi_json (1.0.4) ... Your bundle is complete! It was installed to ./vendor/bundle
Step 2: Move it to releases
Once the project has been built, it will be moved to
releases/. A symlink called
current/ will be created to point to the active release.
$ -----> Moving to releases/4 $ mv "./tmp/build-128293482394" "releases/4" -----> Symlinking to current $ ln -nfs releases/4 current
Step 3: Launch it
Invoke the commands queued up in the
to :launch block. These often commands to restart the webserver process. Once this in complete, you’re done!
$ -----> Launching $ cd releases/4 $ sudo service nginx restart -----> Done. Deployed v4
What about failure?
If it fails at any point, the release path will be deleted. If any commands are queued using the
to :clean block, they will be ran. It will be as if nothing happened. Lets see what happens if a build fails:
$ -----> Launching $ cd releases/4 $ sudo service nginx restart Starting nginx... error: can't start service -----> ERROR: Deploy failed. -----> Cleaning up build $ rm -rf tmp/build-128293482394 -----> Unlinking current $ ln -nfs releases/3 current OK