How can you check to see if a file exists (on the remote server) in Capistrano?

Question

Like many others I\'ve seen in the Googleverse, I fell victim to the File.exists? trap, which of course checks your local file system, not the server y

Answer 1

Inspired by @bhups response, with tests:

def remote_file_exists?(full_path)
  'true' ==  capture("if [ -e #{full_path} ]; then echo 'true'; fi").strip
end

namespace :remote do
  namespace :file do
    desc "test existence of missing file"
    task :missing do
      if remote_file_exists?('/dev/mull')
        raise "It's there!?"
      end
    end

    desc "test existence of present file"
    task :exists do
      unless remote_file_exists?('/dev/null')
        raise "It's missing!?"
      end
    end
  end
end