如何设置服务器进行部署并使用 Capistrano 进行冷部署？

Question

deploy:setup 和使用 Capistrano 进行冷部署的正确方法是什么？

使用

• this deploy.rb
• Capistrano v2.14.2
• Vagrant 虚拟化我的服务器，

这是我的场景：

1. 在运行deploy:setup 时，Capistrano 使用 root 权限来准备目录结构以进行部署：

   $ cap deploy:setup
     * 2013-02-28 14:50:21 executing `deploy:setup'
     * executing "sudo -p 'sudo password: ' mkdir -p /home/vagrant/example /home/vagrant/example/releases /home/vagrant/example/shared /home/vagrant/example/shared/system /home/vagrant/example/shared/log /home/vagrant/example/shared/pids"
       servers: ["example.com"]
       [example.com] executing command
       command finished in 29ms
     * executing "sudo -p 'sudo password: ' chmod g+w /home/vagrant/example /home/vagrant/example/releases /home/vagrant/example/shared /home/vagrant/example/shared/system /home/vagrant/example/shared/log /home/vagrant/example/shared/pids"
       servers: ["example.com"]
       [example.com] executing command
       command finished in 11ms
   

2. 然而在deploy:cold Capistrano 尝试结帐（在这种情况下从 git）并以vagrant 用户的身份写入 - 在deploy.rb 中指定的用户：

   $ cap deploy:cold
     * 2013-02-28 14:50:47 executing `deploy:cold'
     * 2013-02-28 14:50:47 executing `deploy:update'
    ** transaction: start
     * 2013-02-28 14:50:47 executing `deploy:update_code'
       updating the cached checkout on all servers
       executing locally: "git ls-remote git@github.com:mariusbutuc/realtime-faye.git master"
       command finished in 2360ms
     * executing "if [ -d /home/vagrant/example/shared/cached-copy ]; then cd /home/vagrant/example/shared/cached-copy && git fetch -q origin && git fetch --tags -q origin && git reset -q --hard a7c05516bc31c2c18f89057c02f84bfad83a6b59 && git clean -q -d -x -f; else git clone -q git@github.com:mariusbutuc/realtime-faye.git /home/vagrant/example/shared/cached-copy && cd /home/vagrant/example/shared/cached-copy && git checkout -q -b deploy a7c05516bc31c2c18f89057c02f84bfad83a6b59; fi"
       servers: ["example.com"]
       [example.com] executing command
    ** [example.com :: out] fatal: could not create work tree dir '/home/vagrant/example/shared/cached-copy'.: Permission denied
       command finished in 26ms
   *** [deploy:update_code] rolling back
     * executing "rm -rf /home/vagrant/example/releases/20130228195049; true"
       servers: ["example.com"]
       [example.com] executing command
       command finished in 7ms
   failed: "sh -c 'if [ -d /home/vagrant/example/shared/cached-copy ]; then cd /home/vagrant/example/shared/cached-copy && git fetch -q origin && git fetch --tags -q origin && git reset -q --hard a7c05516bc31c2c18f89057c02f84bfad83a6b59 && git clean -q -d -x -f; else git clone -q git@github.com:mariusbutuc/realtime-faye.git /home/vagrant/example/shared/cached-copy && cd /home/vagrant/example/shared/cached-copy && git checkout -q -b deploy a7c05516bc31c2c18f89057c02f84bfad83a6b59; fi'" on example.com
   

3. 当然，deploy:check 报告并不令人意外：vagrant 用户无法写入在 deploy:setup 期间创建的目录，因为这两个用户属于不同的组 - root:root 与 vagrant:vagrant：

   $ cap deploy:check
     [...]
   The following dependencies failed. Please check them and try again:
   --> You do not have permissions to write to `/home/vagrant/example'. (example.com)
   --> You do not have permissions to write to `/home/vagrant/example/releases'. (example.com)
   --> `/home/vagrant/example/shared' is not writable (example.com)
   

这背后的原因是什么，什么先决条件还没有满足，所以部署通过了这个问题？

Answer 1

deploy:setup 任务可能不应该使用sudo 来创建应用目录，因为这很可能导致它归root 所有。

您可以在 deploy.rb 文件中关闭它：

set :use_sudo, false

Answer 2

由于有no group setting in Capistrano，我的解决方法是扩展这样的设置，例如：

set :user,  'vagrant'
set :group, 'vagrant'

然后在运行deploy:setup后创建一个任务来“修复”所有权：

after "deploy:setup", :setup_ownership
task :setup_ownership do
  run "#{sudo} chown -R #{user}:#{group} #{deploy_to} && chmod -R g+s #{deploy_to}"
end

但唯一比解决问题更好的方法是一开始就没有它，所以Stuart's answer 更聪明也更优雅。