Heroku 上的非 Rails 应用程序在 config.ru 中有什么内容？

Question

我有一个简单的 ruby​​（非 Rails）应用程序，它使用 resque，如果没有 heroku 上的 config.ru，将无法启动。当我添加 config.ru 文件时，在本地运行 rackup 时出现以下错误：

/usr/local/Cellar/ruby/1.9.3-p194/lib/ruby/gems/1.9.1/gems/rack-1.5.2/lib/rack/builder.rb:133:in `to_app': missing run or map statement (RuntimeError)
from /Users/nickkarrasch/Dropbox/Coding/Ruby/smsnotifyv2/config.ru:in `<main>'
from /usr/local/Cellar/ruby/1.9.3-p194/lib/ruby/gems/1.9.1/gems/rack-1.5.2/lib/rack/builder.rb:49:in `eval'
from /usr/local/Cellar/ruby/1.9.3-p194/lib/ruby/gems/1.9.1/gems/rack-1.5.2/lib/rack/builder.rb:49:in `new_from_string'
from /usr/local/Cellar/ruby/1.9.3-p194/lib/ruby/gems/1.9.1/gems/rack-1.5.2/lib/rack/builder.rb:40:in `parse_file'
from /usr/local/Cellar/ruby/1.9.3-p194/lib/ruby/gems/1.9.1/gems/rack-1.5.2/lib/rack/server.rb:277:in `build_app_and_options_from_config'
from /usr/local/Cellar/ruby/1.9.3-p194/lib/ruby/gems/1.9.1/gems/rack-1.5.2/lib/rack/server.rb:199:in `app'
from /usr/local/Cellar/ruby/1.9.3-p194/lib/ruby/gems/1.9.1/gems/rack-1.5.2/lib/rack/server.rb:314:in `wrapped_app'
from /usr/local/Cellar/ruby/1.9.3-p194/lib/ruby/gems/1.9.1/gems/rack-1.5.2/lib/rack/server.rb:250:in `start'
from /usr/local/Cellar/ruby/1.9.3-p194/lib/ruby/gems/1.9.1/gems/rack-1.5.2/lib/rack/server.rb:141:in `start'
from /usr/local/Cellar/ruby/1.9.3-p194/lib/ruby/gems/1.9.1/gems/rack-1.5.2/bin/rackup:4:in `<top (required)>'
from /usr/local/Cellar/ruby/1.9.3-p194/bin/rackup:23:in `load'
from /usr/local/Cellar/ruby/1.9.3-p194/bin/rackup:23:in `<main>'

我需要在 config.ru 中添加什么？

Answer 1

该文件 (config.ru) 的内容将取决于您实际尝试执行的操作以及您使用的框架，因为它仅用于配置 Rack 应用程序，它告诉Rack::Builder 应该使用什么中间件以及使用顺序。这些是 Heroku 文档for deploying rack applications. 中提供的一些示例：

辛纳特拉：

require './hello'
run Sinatra::Application

拉玛兹：

require ::File.expand_path('./../hello', __FILE__)
Ramaze.start(:file => __FILE__, :started => true)
run Ramaze

露营

require './hello'
run Rack::Adapter::Camping.new(Hello)