a.rb

namespace :redis do
  namespace :flush do
    desc "Flushes all redis cached moldbi views"
    task :moldbi do
      on roles(:db) do
        execute "redis-cli KEYS \"moldbi/*\" | xargs redis-cli DEL"
      end
    end

    desc "Flushes all redis cached moldbi resources"
    task :moldbi_resources do
      on roles(:db) do
        execute "redis-cli KEYS \"moldbi/*/resource\" | xargs redis-cli DEL"
      end
    end
  end
end