assets:copy_to_s3 rake task

copy_assets_to_s3.rake

namespace :assets do
  desc 'copy precompiled assets to S3'
  task :copy_to_s3 => :environment do
    Rails.logger.info('Copying compiled assets to s3...')
    s3 = AWS::S3.new
    bucket = s3.buckets[APP_CONFIG[:rails_assets_bucket]]
    base_dir = Rails.root.join('public', 'assets').to_s + '/'

    regexp_extensions   = []
    ['js', 'css', 'html', 'png', 'jpg', 'jpeg', 'gif', 'ttf', 'woff', 'svg', 'eot', 'otf'].each do |ext|
      regexp_extensions << "\\.#{ext}"
      regexp_extensions << "\\.#{ext}\\.gz"
    end
    regexp = /#{regexp_extensions.join('|')}$/i

    gzip_lookup = {}
    Dir[Rails.root.join('public', 'assets', '**/*.gz')].each do |asset_file_path|
      # Overwrite non-gzipped files with gzipped
      omit_gz_file_path = asset_file_path.sub(/\.gz$/, '')
      FileUtils.mv(asset_file_path, omit_gz_file_path)
      key = path_to_key(omit_gz_file_path, base_dir)
      gzip_lookup[key] = true
    end

    Dir[Rails.root.join('public', 'assets', '**/*.*')].each do |asset_file_path|
      copy_file_to_s3(regexp, bucket, base_dir, asset_file_path, gzip_lookup)
    end
  end

  def path_to_key(asset_file_path, base_dir)
    asset_file_path.sub(base_dir, '')
  end

  def copy_file_to_s3(regexp, bucket, base_dir, asset_file_path, gzip_lookup, force_upload=false)
    key = path_to_key(asset_file_path, base_dir)
    if key =~ regexp
      if key =~ /\.js(\.gz)?$/i
        content_type = 'application/javascript'
      elsif key =~ /\.css(\.gz)?$/i
        content_type = 'text/css'
      elsif key =~ /\.html(\.gz)?$/i
        content_type = 'text/html'
      elsif key =~ /\.png(\.gz)?$/i
        content_type = 'image/png'
      elsif key =~ /\.je?pg(\.gz)?$/i
        content_type = 'image/jpeg'
      elsif key =~ /\.gif(\.gz)?$/i
        content_type = 'image/gif'
      elsif key =~ /\.ttf(\.gz)?$/i
        content_type = 'application/x-font-ttf'
      elsif key =~ /\.woff(\.gz)?$/i
        content_type = 'application/x-font-woff'
      elsif key =~ /\.svg(\.gz)?$/i
        content_type = 'image/svg+xml'
      elsif key =~ /\.eot(\.gz)?$/i
        content_type = 'application/vnd.ms-fontobject'
      elsif key =~ /\.otf(\.gz)?$/i
        content_type = 'application/octet-stream'
      else
        content_type = nil
      end

      s3_object = bucket.objects["assets/#{key}"]
      if force_upload || !s3_object.exists?
        options = {
                    :file => asset_file_path,
                    :acl => :public_read,
                    :content_type => content_type,
                    :cache_control => 'public, max-age=31557600'
                  }
        options[:content_encoding] = 'gzip' if gzip_lookup[key]
        Rails.logger.info("uploading #{key}")
        Rails.logger.info('     gzipped') if gzip_lookup[key]
        s3_object.write(options)
      else
        Rails.logger.info("#{key} already exists")
      end
    end
  end
end