Tagging release before deploying with Capistrano

Thanks to @dunedain289 for a great answer. I took it a step further to try replicate heroku releases for capistrano. I needed a nice tool to know what was already deployed on the servers, and to make a diff with my current local branch:

1. first, use @dunedain289's code, slightly modified to work for me

   task :push_deploy_tag do
      user = `git config --get user.name`.chomp
      email = `git config --get user.email`.chomp
      stage = "production" unless stage # hack, stage undefined for me
      puts `git tag #{stage}_#{release_name} -m "Deployed by #{user} <#{email}>"`
      puts `git push --tags origin`
    end
   

2. Add a task to filter the release tags and diff the last

   task :diff do
     stage = "production" unless stage
     last_stage_tag = `git tag -l #{stage}* | tail -1`
     system("git diff #{last_stage_tag}", out: $stdout, err: :out)
   end
   
   #this preserves coloring if you have a .gitconfig with 
   [color "diff"]
     meta = yellow bold
     frag = magenta bold
     old = red bold
     new = green bold
   

3. execute

   $ cap diff
   # awesome colored diff of production and local
   

Just add the short hash of the commit you are building from.

git log -1 --format=%h

I've done something similar with Capistrano. The easiest thing to do is tag using the timestamp name that Capistrano used during the deploy - that's YYYYMMDDHHMMSS, so it's really hard to get duplicates.

Example:

task :push_deploy_tag do
  user = `git config --get user.name`.chomp
  email = `git config --get user.email`.chomp
  puts `git tag #{stage}_#{release_name} #{current_revision} -m "Deployed by #{user} <#{email}>"`
  puts `git push --tags origin`
end

Regarding your question in the code about how to output the text via Capistrano. Just change p to puts and it displays fine.