Ruby on rails 要求'安全吗；打开uri'；在Rails项目中？

我已经看过很多开放uri的例子，对于简单的事情来说，它似乎非常棒。但是，要求它在全局范围内定义一个名为

open

的方法，这确实让我感到不安

这尤其令人不安，因为在Rails 5控制台中四处搜索之后，似乎已经定义了一个名为

open

的方法：

irb(main):001:0> open
ArgumentError: wrong number of arguments (given 0, expected 1..3)
        from (irb):1:in `initialize'
        from (irb):1:in `open'
        from (irb):1
        from /Users/ahamon/.gem/ruby/2.3.0/gems/railties-5.0.0.beta3/lib/rails/commands/console.rb:65:in `start'
        from /Users/ahamon/.gem/ruby/2.3.0/gems/railties-5.0.0.beta3/lib/rails/commands/console_helper.rb:9:in `start'
        from /Users/ahamon/.gem/ruby/2.3.0/gems/railties-5.0.0.beta3/lib/rails/commands/commands_tasks.rb:78:in `console'
        from /Users/ahamon/.gem/ruby/2.3.0/gems/railties-5.0.0.beta3/lib/rails/commands/commands_tasks.rb:49:in `run_command!'
        from /Users/ahamon/.gem/ruby/2.3.0/gems/railties-5.0.0.beta3/lib/rails/command.rb:20:in `run'
        from /Users/ahamon/.gem/ruby/2.3.0/gems/railties-5.0.0.beta3/lib/rails/commands.rb:18:in `<top (required)>'
        from /Users/ahamon/.gem/ruby/2.3.0/gems/activesupport-5.0.0.beta3/lib/active_support/dependencies.rb:302:in `require'
        from /Users/ahamon/.gem/ruby/2.3.0/gems/activesupport-5.0.0.beta3/lib/active_support/dependencies.rb:302:in `block in require'
        from /Users/ahamon/.gem/ruby/2.3.0/gems/activesupport-5.0.0.beta3/lib/active_support/dependencies.rb:268:in `load_dependency'
        from /Users/ahamon/.gem/ruby/2.3.0/gems/activesupport-5.0.0.beta3/lib/active_support/dependencies.rb:302:in `require'
        from /Users/ahamon/code/signist/bin/rails:9:in `<top (required)>'
        from /Users/ahamon/.gem/ruby/2.3.0/gems/activesupport-5.0.0.beta3/lib/active_support/dependencies.rb:296:in `load'
        from /Users/ahamon/.gem/ruby/2.3.0/gems/activesupport-5.0.0.beta3/lib/active_support/dependencies.rb:296:in `block in load'
        from /Users/ahamon/.gem/ruby/2.3.0/gems/activesupport-5.0.0.beta3/lib/active_support/dependencies.rb:268:in `load_dependency'
        from /Users/ahamon/.gem/ruby/2.3.0/gems/activesupport-5.0.0.beta3/lib/active_support/dependencies.rb:296:in `load'
        from /Users/ahamon/.gem/ruby/2.3.0/gems/spring-1.6.4/lib/spring/commands/rails.rb:6:in `call'
        from /Users/ahamon/.gem/ruby/2.3.0/gems/spring-1.6.4/lib/spring/command_wrapper.rb:38:in `call'
        from /Users/ahamon/.gem/ruby/2.3.0/gems/spring-1.6.4/lib/spring/application.rb:185:in `block in serve'
        from /Users/ahamon/.gem/ruby/2.3.0/gems/spring-1.6.4/lib/spring/application.rb:156:in `fork'
        from /Users/ahamon/.gem/ruby/2.3.0/gems/spring-1.6.4/lib/spring/application.rb:156:in `serve'
        from /Users/ahamon/.gem/ruby/2.3.0/gems/spring-1.6.4/lib/spring/application.rb:131:in `block in run'
        from /Users/ahamon/.gem/ruby/2.3.0/gems/spring-1.6.4/lib/spring/application.rb:125:in `loop'
        from /Users/ahamon/.gem/ruby/2.3.0/gems/spring-1.6.4/lib/spring/application.rb:125:in `run'
        from /Users/ahamon/.gem/ruby/2.3.0/gems/spring-1.6.4/lib/spring/application/boot.rb:18:in `<top (required)>'
        from /Users/ahamon/.rubies/ruby-2.3.0/lib/ruby/2.3.0/rubygems/core_ext/kernel_require.rb:55:in `require'
        from /Users/ahamon/.rubies/ruby-2.3.0/lib/ruby/2.3.0/rubygems/core_ext/kernel_require.rb:55:in `require'
        from -e:1:in `<main>'irb(main):002:0>

请注意每个堆栈跟踪中指定的不同arity

那么以前定义的

打开的
是什么？抹杀是安全的吗？有没有一种方法可以在不定义全局方法的情况下使用OpenURI？
open
是，而不是Rails。包装
Kernel#open
：它检查目标是否是URL或知道
#open
，如果是，则处理它，如果不是，则将所有内容传递给real
Kernel#open

因此，如果没有
openuri
，url就不能工作，openables就不能工作，其他一切都可以。使用
openuri
，url工作，openables工作，其他一切都是一样的。除了当
open uri
检查您的参数是否是URL或响应
#open
时，性能会受到非常非常轻微的影响之外，要求它应该没有危险

irb(main):002:0> require 'open-uri'
=> true
irb(main):003:0> open
ArgumentError: wrong number of arguments (given 0, expected 1+)
        from /Users/ahamon/.rubies/ruby-2.3.0/lib/ruby/2.3.0/open-uri.rb:29:in `open'
        from (irb):3
        from /Users/ahamon/.gem/ruby/2.3.0/gems/railties-5.0.0.beta3/lib/rails/commands/console.rb:65:in `start'
        from /Users/ahamon/.gem/ruby/2.3.0/gems/railties-5.0.0.beta3/lib/rails/commands/console_helper.rb:9:in `start'
        from /Users/ahamon/.gem/ruby/2.3.0/gems/railties-5.0.0.beta3/lib/rails/commands/commands_tasks.rb:78:in `console'
        from /Users/ahamon/.gem/ruby/2.3.0/gems/railties-5.0.0.beta3/lib/rails/commands/commands_tasks.rb:49:in `run_command!'
        from /Users/ahamon/.gem/ruby/2.3.0/gems/railties-5.0.0.beta3/lib/rails/command.rb:20:in `run'
        from /Users/ahamon/.gem/ruby/2.3.0/gems/railties-5.0.0.beta3/lib/rails/commands.rb:18:in `<top (required)>'
        from /Users/ahamon/.gem/ruby/2.3.0/gems/activesupport-5.0.0.beta3/lib/active_support/dependencies.rb:302:in `require'
        from /Users/ahamon/.gem/ruby/2.3.0/gems/activesupport-5.0.0.beta3/lib/active_support/dependencies.rb:302:in `block in require'
        from /Users/ahamon/.gem/ruby/2.3.0/gems/activesupport-5.0.0.beta3/lib/active_support/dependencies.rb:268:in `load_dependency'
        from /Users/ahamon/.gem/ruby/2.3.0/gems/activesupport-5.0.0.beta3/lib/active_support/dependencies.rb:302:in `require'
        from /Users/ahamon/code/signist/bin/rails:9:in `<top (required)>'
        from /Users/ahamon/.gem/ruby/2.3.0/gems/activesupport-5.0.0.beta3/lib/active_support/dependencies.rb:296:in `load'
        from /Users/ahamon/.gem/ruby/2.3.0/gems/activesupport-5.0.0.beta3/lib/active_support/dependencies.rb:296:in `block in load'
        from /Users/ahamon/.gem/ruby/2.3.0/gems/activesupport-5.0.0.beta3/lib/active_support/dependencies.rb:268:in `load_dependency'
        from /Users/ahamon/.gem/ruby/2.3.0/gems/activesupport-5.0.0.beta3/lib/active_support/dependencies.rb:296:in `load'
        from /Users/ahamon/.gem/ruby/2.3.0/gems/spring-1.6.4/lib/spring/commands/rails.rb:6:in `call'
        from /Users/ahamon/.gem/ruby/2.3.0/gems/spring-1.6.4/lib/spring/command_wrapper.rb:38:in `call'
        from /Users/ahamon/.gem/ruby/2.3.0/gems/spring-1.6.4/lib/spring/application.rb:185:in `block in serve'
        from /Users/ahamon/.gem/ruby/2.3.0/gems/spring-1.6.4/lib/spring/application.rb:156:in `fork'
        from /Users/ahamon/.gem/ruby/2.3.0/gems/spring-1.6.4/lib/spring/application.rb:156:in `serve'
        from /Users/ahamon/.gem/ruby/2.3.0/gems/spring-1.6.4/lib/spring/application.rb:131:in `block in run'
        from /Users/ahamon/.gem/ruby/2.3.0/gems/spring-1.6.4/lib/spring/application.rb:125:in `loop'
        from /Users/ahamon/.gem/ruby/2.3.0/gems/spring-1.6.4/lib/spring/application.rb:125:in `run'
        from /Users/ahamon/.gem/ruby/2.3.0/gems/spring-1.6.4/lib/spring/application/boot.rb:18:in `<top (required)>'
        from /Users/ahamon/.rubies/ruby-2.3.0/lib/ruby/2.3.0/rubygems/core_ext/kernel_require.rb:55:in `require'
        from /Users/ahamon/.rubies/ruby-2.3.0/lib/ruby/2.3.0/rubygems/core_ext/kernel_require.rb:55:in `require'
        from -e:1:in `<main>'irb(main):004:0>