A rake task to audit gems against latest versions

gemfile_audit.rake

# Instructions:
#
# 1. Make sure to add the `gems` gem to your Gemfile so this can work:
#    https://rubygems.org/gems/gems
#
# 2. Register at RubyGems.org and add your API key to ~/.gem/credentials
#    and chmod the credentials file to 0600
#
# 3. Use this content to create `lib/tasks/gemfile_audit.rake`
#
# 4. Run `bundle exec rake gemfile:audit`
#
# 5. It will create `gems_data.csv` in the application root. Open it and
#    go wild organizing your new spreadsheet.
#
desc 'Run through the gemfile and build a spreadsheet of knowledge of the gems'
namespace :gemfile do
  task :audit => :environment do
    require 'csv'

 
    gems = []

    # Let's get the gemfile lines in an array
    File.open('Gemfile').each do |line|
      gems << line.strip.gsub(/gem\s/, '') if line =~ /gem\s/
    end

    gems_data = []

    # Now let's parse all of the gems and get the relevant meta data
    gems.each do |line|
      clean_line = line.delete("'~>=,#\"").strip

      bits = clean_line.split(' ')

      gem_name = bits[0]
      gem_version = bits[1]

      puts "Fetching #{gem_name}..."

      begin
        # Let's fetch the info on the current versions of the gem...
        latest_version = Gems.versions(gem_name).first
        info = Gems.info(gem_name)

        created_at = Date.parse(latest_version["created_at"])
        age = ((Date.current - created_at).to_f/365).round(2)

        values = {
          name: gem_name,
          current_version: gem_version,
          latest_version: latest_version["number"],
          years_old: age,
          created_at: created_at.strftime('%b %d, %Y'),
          latest_prerelease: latest_version["prerelease"],
          downloads: info["downloads"],
          summary: latest_version["summary"],
          string: line
        }
      rescue
        puts "  #{gem_name} not found."
        values = {
          name: gem_name,
          current_version: gem_version,
          latest_version: '',
          years_old: '',
          created_at: '',
          latest_prerelease: '',
          downloads: '',
          summary: '',
          string: line
        }
      end

      gems_data << values
    end

    gems_data.compact!

    CSV.open("gems_data.csv", "wb") do |csv|
      csv << gems_data.first.keys
      gems_data.each do |gem|
        csv << gem.values
      end
    end
  end
end