ruby-on-rails - 为 rails/heroku 组合 rake 任务不起作用

Question

我从这个（http://stackoverflow.com/questions/1890709/combining-many-rake-tasks-into-one-rake-task）看到你可以像这样组合 rake 任务：

desc 'This rebuilds development db'
task :rebuild_dev => ["db:drop", "db:create", "db:migrate", "db:load"]

但是，当我尝试对我的本地应用程序执行此操作以组合相对简单的 rake 任务时，每个任务都只运行 shell 命令，似乎它只执行数组中的第一个 ['heroku:push', 'heroku:migrate', 'heroku:restart']。

这是代码：

desc 'Push to heroku production, db:migrate, and restart app'
task :deploy_production => ['heroku:push', 'heroku:migrate', 'heroku:restart']

namespace :heroku do
  task :push do
    puts 'Deploying app to Heroku...'
    exec 'git push heroku master'
  end

  task :migrate do
    puts 'Running database migrations ...'
    exec 'heroku run rake db:migrate'
  end

  task :restart do
    puts 'Restarting app servers ...'
    exec 'heroku restart'
  end
end

顺便说一下，如果你需要它，这里是 rake 的版本：

$ gem list | grep rake                                                               
rake (0.9.2.2)

Answer 1

I should use backticks (`) instead of the exec ruby command. Here's what the code should like for the rake deploy_production to work:

desc 'Push to heroku production, db:migrate, and restart app'
task :deploy_production => ['heroku:push', 'heroku:migrate', 'heroku:restart']

namespace :heroku do
  task :push do
    puts 'Deploying app to Heroku...'
    `git push heroku master`
  end

  task :migrate do
    puts 'Running database migrations ...'
    `heroku run rake db:migrate`
  end

  task :restart do
    puts 'Restarting app servers ...'
    `heroku restart`
  end
end

I had problems posting it immediately because I am new to stackoverflow, and I can't post an answer immediately to my own question.

The reason I prefer backticks over system in ruby is because of the slight advantage discussed here: Ruby, Difference between exec, system and %x() or Backticks

Answer 2

尝试做

desc 'Push to heroku production, db:migrate, and restart app'
task :deploy_production => ['heroku:push', 'heroku:migrate', 'heroku:restart']

namespace :heroku do
  task :push do
    puts 'Deploying app to Heroku...'
    system 'git push heroku master'
  end

  task :migrate do
    puts 'Running database migrations ...'
    system 'heroku run rake db:migrate'
  end

  task :restart do
    puts 'Restarting app servers ...'
    system 'heroku restart'
  end
end

所以基本上只是用电话代替exec电话system。