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我正在将一个简单的 Rails 应用程序部署到这个小型 ubuntu 精确 64 服务器设置：
* 1 个运行 nginx 的 Web 服务器
* 2 个运行 unicorn 的应用程序服务器
* 1 个运行 postgresql 的数据库服务器

我的服务器配备了 Puppet，我正在使用 capistrano 推送应用程序。

我的Capfile

load 'deploy'
# Uncomment if you are using Rails' asset pipeline
load 'deploy/assets'
load 'config/deploy' # remove this line to skip loading any of the default tasks

deploy.rb 文件超级简单

# Execute "bundle install" after deploy, but only when really needed
require "bundler/capistrano"

# Name of the application in scm (GIT)
set :application, "devops-test-app"
set :repository, "https://github.com/geoffroymontel/devops-test-app.git"
set :scm, :git

set :deploy_to, "/var/www/#{application}"

# server there the web server is running (nginx)
role :web, "172.16.0.2"

# server there the db is running
# This is where Rails migrations will run
role :db, "172.16.0.3", :primary => true

# servers there the app servers are running (unicorn)
role :app, "172.16.0.4", "172.16.0.5"

set :rails_env, :production

# user on the server
set :user, "deployer"
set :use_sudo, false

namespace :deploy do 
  task :start, :roles => :app, :except => { :no_release => true } do
    run "service unicorn_#{application} start"
  end

  task :stop, :roles => :app, :except => { :no_release => true } do
    run "service unicorn_#{application} stop"
  end

  task :restart, :roles => :app, :except => { :no_release => true } do
    run "service unicorn_#{application} restart"
  end

  task :copy_in_database_yml do
    run "cp #{shared_path}/config/database.yml #{latest_release}/config/"
  end

  # Precompile assets
  # I have to precompile the assets on the app servers too, and I don't really know why...
  # namespace :assets do
  #   task :precompile, :roles => [:web, :app], :except => { :no_release => true } do
  #     run %Q{cd #{latest_release} && #{rake} RAILS_ENV=#{rails_env} #{asset_env} assets:precompile}
  #   end
  # end
end

before "deploy:assets:precompile", "deploy:copy_in_database_yml"

如果我不在应用服务器上预编译资产，应用程序将失败。

$ cap ROLES="app" COMMAND="cat /var/www/devops-test-app/current/log/production.log" invoke
  * 2013-05-01 21:43:10 executing `invoke'
  * executing "cat /var/www/devops-test-app/current/log/production.log"
    servers: ["172.16.0.4", "172.16.0.5"]
    [172.16.0.5] executing command
 ** [out :: 172.16.0.5] Connecting to database specified by database.yml
 ** [out :: 172.16.0.5] Connecting to database specified by database.yml
 ** [out :: 172.16.0.5] Started GET "/posts" for 172.16.0.2 at 2013-05-01 19:42:10 +0000
 ** [out :: 172.16.0.5] Processing by PostsController#index as HTML
 ** [out :: 172.16.0.5] Rendered posts/index.html.erb within layouts/application (25.7ms)
 ** [out :: 172.16.0.5] Completed 500 Internal Server Error in 122ms
 ** [out :: 172.16.0.5] 
 ** [out :: 172.16.0.5] ActionView::Template::Error (application.css isn't precompiled):
 ** [out :: 172.16.0.5] 2: <html>
 ** [out :: 172.16.0.5] 3: <head>
 ** [out :: 172.16.0.5] 4:   <title>DevopsTestApp</title>
 ** [out :: 172.16.0.5] 5:   <%= stylesheet_link_tag    "application", :media => "all" %>
 ** [out :: 172.16.0.5] 6:   <%= javascript_include_tag "application" %>
 ** [out :: 172.16.0.5] 7:   <%= csrf_meta_tags %>
 ** [out :: 172.16.0.5] 8: </head>
 ** [out :: 172.16.0.5] app/views/layouts/application.html.erb:5:in `_app_views_layouts_application_html_erb__677166568443748084_17536100'
 ** [out :: 172.16.0.5] app/controllers/posts_controller.rb:7:in `index'

如果我取消注释中的注释行deploy.rb，一切都很好。

但为什么 ？？我认为您只需要在 Web 服务器上编译资产，而不是在应用服务器上。

请帮我理解为什么:)

谢谢，最好的问候

杰弗里

4

3 回答 3

3

因为，除其他外，Rails 会生成预编译资产的清单，包括文件名中文件的哈希值，然后在页面中包含资产时使用这些名称。当你说image_url('foo.jpg')，Rails 最终会foo-b48cf0140bea12734db05ebcdb012f1d265bed84.jpg在源代码中生成。

Rails 需要知道这些资产使用什么编译名称，所以它必须有清单，所以预编译需要在应用服务器上完成。

看一下public/assets/manifest.yml- 这是 Rails 需要的文件，以便正确地提供预编译资产。

于 2013-05-02T17:25:46.897 回答
2

这是 Capistrano 中的一个已知错误。

1条评论

load 'deploy/assets'

在你的Capfile.

2）在文件顶部添加以下行deploy.rb：

set :assets_role, [:web, :app]
load 'deploy/assets'

而已 ！

于 2013-05-03T13:02:36.970 回答
1

确保您已将 Nginx 配置为在不访问应用程序服务器的情况下提供静态文件。这很可能没有配置，因此资产存在，但 Nginx 没有为它们提供服务并且正在回退到应用程序。

于 2013-05-02T17:24:16.810 回答