Capistrano 3在远程服务器上执行任意命令

问题描述

Capistrano 3不再使用命令cap env shell。

现在我们应该使用cap env console

但是它不是交互式的，例如，我们不能使用箭头键来记录或tab按钮上的自动完成

那我该怎么办？

解决方法

我建议编写自己的小耙子任务来完成。使用readline宝石 首先要感谢以下材料：

1. https://thoughtbot.com/blog/tab-completion-in-gnu-readline-ruby-edition

2. How to write a Ruby command line app that supports tab completion?

desc "Remote console" 
task :console do
  require 'readline'
  # https://thoughtbot.com/blog/tab-completion-in-gnu-readline-ruby-edition

  host_args = (ENV['HOSTS'] || '').split(',').map { |r| r.to_sym }
  role_args = (ENV['ROLES'] || '').split(',').map { |r| r.to_sym }

  LIST = `ls /usr/bin`.split("\n").sort + `ls /bin`.split("\n").sort

  comp = proc { |s| LIST.grep(/^#{Regexp.escape(s)}/) }

  Readline.completion_append_character = " "
  Readline.completion_proc = comp

  while line = Readline.readline('cap> ',true)
    begin
      next if line.strip.empty?
      exec_cmd(line,host_args,role_args)
    rescue StandardError => e
      puts e
      puts e.backtrace
    end
  end
end

def exec_cmd(line,role_args)
  line = "RAILS_ENV=#{fetch(:stage)} #{line}" if fetch(:stage)
  cmd = "bash -lc '#{line}'"
  puts "Final command: #{cmd}"
  if host_args.any?
    on hosts host_args do
      execute cmd
    end
  elsif role_args.any?
    on roles role_args do
      execute cmd
    end
  else
    on roles :all do
      execute cmd
    end
  end
end

做点什么，加油！ =））