当我引发RuntimeError时，为什么Sinatra的“show_exceptions.rb”文件崩溃？

Question

我有如此简单的应用程序：

require "sinatra" 

get "/" do 
    raise "Oops!" 
end 

因为这是一个调试环境，我希望看到一个“RuntimeError：哎呀呀”在浏览器中显示。相反，它似乎西纳特拉崩溃：

NoMethodError at/
undefined method `join' for #<String:0x00000002b74bf0> 

Ruby /home/tomas/.rvm/.../gems/sinatra-1.4.5/lib/sinatra/show_exceptions.rb: in rescue in call, line 37 
Web  GET 127.0.0.1/

回溯控制台：

RuntimeError - Oops!: 
    test.rb:5:in `block in ' 
    /home/tomas/.rvm/gems/ruby-2.0.0-p481@test/gems/sinatra-1.4.5/lib/sinatra/base.rb:1603:in `call' 
    /home/tomas/.rvm/gems/ruby-2.0.0-p481@test/gems/sinatra-1.4.5/lib/sinatra/base.rb:1603:in `block in compile!' 
    /home/tomas/.rvm/gems/ruby-2.0.0-p481@test/gems/sinatra-1.4.5/lib/sinatra/base.rb:966:in `[]' 
    /home/tomas/.rvm/gems/ruby-2.0.0-p481@test/gems/sinatra-1.4.5/lib/sinatra/base.rb:966:in `block (3 levels) in route!' 
    /home/tomas/.rvm/gems/ruby-2.0.0-p481@test/gems/sinatra-1.4.5/lib/sinatra/base.rb:985:in `route_eval' 
    /home/tomas/.rvm/gems/ruby-2.0.0-p481@test/gems/sinatra-1.4.5/lib/sinatra/base.rb:966:in `block (2 levels) in route!' 
    /home/tomas/.rvm/gems/ruby-2.0.0-p481@test/gems/sinatra-1.4.5/lib/sinatra/base.rb:1006:in `block in process_route' 
    /home/tomas/.rvm/gems/ruby-2.0.0-p481@test/gems/sinatra-1.4.5/lib/sinatra/base.rb:1004:in `catch' 
    /home/tomas/.rvm/gems/ruby-2.0.0-p481@test/gems/sinatra-1.4.5/lib/sinatra/base.rb:1004:in `process_route' 
    /home/tomas/.rvm/gems/ruby-2.0.0-p481@test/gems/sinatra-1.4.5/lib/sinatra/base.rb:964:in `block in route!' 
    /home/tomas/.rvm/gems/ruby-2.0.0-p481@test/gems/sinatra-1.4.5/lib/sinatra/base.rb:963:in `each' 
    /home/tomas/.rvm/gems/ruby-2.0.0-p481@test/gems/sinatra-1.4.5/lib/sinatra/base.rb:963:in `route!' 
    /home/tomas/.rvm/gems/ruby-2.0.0-p481@test/gems/sinatra-1.4.5/lib/sinatra/base.rb:1076:in `block in dispatch!' 
    /home/tomas/.rvm/gems/ruby-2.0.0-p481@test/gems/sinatra-1.4.5/lib/sinatra/base.rb:1058:in `block in invoke' 
    /home/tomas/.rvm/gems/ruby-2.0.0-p481@test/gems/sinatra-1.4.5/lib/sinatra/base.rb:1058:in `catch' 
    /home/tomas/.rvm/gems/ruby-2.0.0-p481@test/gems/sinatra-1.4.5/lib/sinatra/base.rb:1058:in `invoke' 
    /home/tomas/.rvm/gems/ruby-2.0.0-p481@test/gems/sinatra-1.4.5/lib/sinatra/base.rb:1073:in `dispatch!' 
    /home/tomas/.rvm/gems/ruby-2.0.0-p481@test/gems/sinatra-1.4.5/lib/sinatra/base.rb:898:in `block in call!' 
    /home/tomas/.rvm/gems/ruby-2.0.0-p481@test/gems/sinatra-1.4.5/lib/sinatra/base.rb:1058:in `block in invoke' 
    /home/tomas/.rvm/gems/ruby-2.0.0-p481@test/gems/sinatra-1.4.5/lib/sinatra/base.rb:1058:in `catch' 
    /home/tomas/.rvm/gems/ruby-2.0.0-p481@test/gems/sinatra-1.4.5/lib/sinatra/base.rb:1058:in `invoke' 
    /home/tomas/.rvm/gems/ruby-2.0.0-p481@test/gems/sinatra-1.4.5/lib/sinatra/base.rb:898:in `call!' 
    /home/tomas/.rvm/gems/ruby-2.0.0-p481@test/gems/sinatra-1.4.5/lib/sinatra/base.rb:886:in `call' 
    /home/tomas/.rvm/gems/ruby-2.0.0-p481@test/gems/rack-protection-1.5.3/lib/rack/protection/xss_header.rb:18:in `call' 
    /home/tomas/.rvm/gems/ruby-2.0.0-p481@test/gems/rack-protection-1.5.3/lib/rack/protection/path_traversal.rb:16:in `call' 
    /home/tomas/.rvm/gems/ruby-2.0.0-p481@test/gems/rack-protection-1.5.3/lib/rack/protection/json_csrf.rb:18:in `call' 
    /home/tomas/.rvm/gems/ruby-2.0.0-p481@test/gems/rack-protection-1.5.3/lib/rack/protection/base.rb:49:in `call' 
    /home/tomas/.rvm/gems/ruby-2.0.0-p481@test/gems/rack-protection-1.5.3/lib/rack/protection/base.rb:49:in `call' 
    /home/tomas/.rvm/gems/ruby-2.0.0-p481@test/gems/rack-protection-1.5.3/lib/rack/protection/frame_options.rb:31:in `call' 
    /home/tomas/.rvm/gems/ruby-2.0.0-p481@test/gems/rack-1.6.0.beta/lib/rack/logger.rb:15:in `call' 
    /home/tomas/.rvm/gems/ruby-2.0.0-p481@test/gems/rack-1.6.0.beta/lib/rack/commonlogger.rb:33:in `call' 
    /home/tomas/.rvm/gems/ruby-2.0.0-p481@test/gems/sinatra-1.4.5/lib/sinatra/base.rb:217:in `call' 
    /home/tomas/.rvm/gems/ruby-2.0.0-p481@test/gems/sinatra-1.4.5/lib/sinatra/base.rb:210:in `call' 
    /home/tomas/.rvm/gems/ruby-2.0.0-p481@test/gems/rack-1.6.0.beta/lib/rack/head.rb:13:in `call' 
    /home/tomas/.rvm/gems/ruby-2.0.0-p481@test/gems/rack-1.6.0.beta/lib/rack/methodoverride.rb:22:in `call' 
    /home/tomas/.rvm/gems/ruby-2.0.0-p481@test/gems/sinatra-1.4.5/lib/sinatra/show_exceptions.rb:21:in `call' 
    /home/tomas/.rvm/gems/ruby-2.0.0-p481@test/gems/sinatra-1.4.5/lib/sinatra/base.rb:180:in `call' 
    /home/tomas/.rvm/gems/ruby-2.0.0-p481@test/gems/sinatra-1.4.5/lib/sinatra/base.rb:2014:in `call' 
    /home/tomas/.rvm/gems/ruby-2.0.0-p481@test/gems/sinatra-1.4.5/lib/sinatra/base.rb:1478:in `block in call' 
    /home/tomas/.rvm/gems/ruby-2.0.0-p481@test/gems/sinatra-1.4.5/lib/sinatra/base.rb:1788:in `synchronize' 
    /home/tomas/.rvm/gems/ruby-2.0.0-p481@test/gems/sinatra-1.4.5/lib/sinatra/base.rb:1478:in `call' 
    /home/tomas/.rvm/gems/ruby-2.0.0-p481@test/gems/rack-1.6.0.beta/lib/rack/handler/webrick.rb:89:in `service' 
    /home/tomas/.rvm/rubies/ruby-2.0.0-p481/lib/ruby/2.0.0/webrick/httpserver.rb:138:in `service' 
    /home/tomas/.rvm/rubies/ruby-2.0.0-p481/lib/ruby/2.0.0/webrick/httpserver.rb:94:in `run' 
    /home/tomas/.rvm/rubies/ruby-2.0.0-p481/lib/ruby/2.0.0/webrick/server.rb:295:in `block in start_thread' 
[2014-10-08 12:42:42] ERROR NoMethodError: undefined method `join' for #<String:0x007f52e055ce38> 
    /home/tomas/.rvm/gems/ruby-2.0.0-p481@test/gems/sinatra-1.4.5/lib/sinatra/show_exceptions.rb:37:in `rescue in call' 
    /home/tomas/.rvm/gems/ruby-2.0.0-p481@test/gems/sinatra-1.4.5/lib/sinatra/show_exceptions.rb:21:in `call' 
    /home/tomas/.rvm/gems/ruby-2.0.0-p481@test/gems/sinatra-1.4.5/lib/sinatra/base.rb:180:in `call' 
    /home/tomas/.rvm/gems/ruby-2.0.0-p481@test/gems/sinatra-1.4.5/lib/sinatra/base.rb:2014:in `call' 
    /home/tomas/.rvm/gems/ruby-2.0.0-p481@test/gems/sinatra-1.4.5/lib/sinatra/base.rb:1478:in `block in call' 
    /home/tomas/.rvm/gems/ruby-2.0.0-p481@test/gems/sinatra-1.4.5/lib/sinatra/base.rb:1788:in `synchronize' 
    /home/tomas/.rvm/gems/ruby-2.0.0-p481@test/gems/sinatra-1.4.5/lib/sinatra/base.rb:1478:in `call' 
    /home/tomas/.rvm/gems/ruby-2.0.0-p481@test/gems/rack-1.6.0.beta/lib/rack/handler/webrick.rb:89:in `service' 
    /home/tomas/.rvm/rubies/ruby-2.0.0-p481/lib/ruby/2.0.0/webrick/httpserver.rb:138:in `service' 
    /home/tomas/.rvm/rubies/ruby-2.0.0-p481/lib/ruby/2.0.0/webrick/httpserver.rb:94:in `run' 
    /home/tomas/.rvm/rubies/ruby-2.0.0-p481/lib/ruby/2.0.0/webrick/server.rb:295:in `block in start_thread' 
localhost - - [08/Oct/2014:12:42:42 CEST] "GET/HTTP/1.1" 500 340

这是完全无助于我。这里发生了什么？

Answer 1

它看起来像一个recent change in Rack在Sinatra中引入了这个错误，其中has been fixed但修复程序没有（在编写本文时）包含在发行版中。

最简单的修复方法（直到发布更新的Sinatra宝石）将使用较早版本的Rack（该变化目前仅在1.6.0.beta中）。如果你使用的捆扎机，或某个脚本的开始接近这个行添加到您的Gemfile（之前require任何东西），如果你不：

gem 'rack', '1.5.2'