/app/models/repository_observer.rb

class RepositoryObserver < ActiveRecord::Observer
# CREATE DIR Manually
# KNOWN Problem: Changing BitBucket Git Dir in use
# KNOWN Problem: Two Repositorys with the same name from different users

  def before_save(repository)
      Rails.logger.info("before save")
      flag = repository.type == 'Git' || repository.type == 'Repository::Git'
      flag &= repository.url.match('.*(bitbucket.org|github.com).*') 
      if flag 
          base_dir_name = repository.url[/[^\/]+.git/]
          url = repository.url
          user = /^\S*[:\/](.*)\/\S*$/.match( url )
          user = user[1]
          git_dir = Setting.plugin_redmine_bitbucketgit_hook[:bitbucketgit_dir].to_s
          git_dir = git_dir  + '/' + user + '_' + base_dir_name 
          Rails.logger.info git_dir
          redminedir = Dir.getwd + '/'
          Rails.logger.info redminedir+git_dir
          comm_str = ""
          unless Dir[redminedir+git_dir] == []
                #Rails.logger.info "Dir already in use..."
       	        comm_str = 'rm -rf "' + redminedir + git_dir + '" &&'
                #return false
          end
          comm_str += 'git clone --mirror '+ url + ' "'+ redminedir + git_dir +'"'
          b = system(comm_str)
          repository.url = redminedir + git_dir
          return false
      end
  end
  
  private
  def exec(command)
    Rails.logger.info("BitbucketGitHook: Executing command: '#{command}'")
    output = `#{command}`
    Rails.logger.info("BitbucketGitHook: Shell returned '#{output}'")
  end

end