ruby - Ruby 中的 Sinatra 错误处理

Question

我有一个简单的 Sinatra 休息，但我无法捕获错误。我也承认我对 Ruby 和 Sinatra 还很陌生。

当我在 post 端点中引发错误时，我想报告传入的文档。我需要 1) 处理发布结果中的错误(我可以访问 @incoming)或 2) 将传入文档传递给错误并在那里报告。

什么是更好的选择，选项 1 还是选项 2？

• 如果我坚持使用选项 1，我该如何防止错误发现错误(就像它现在所做的那样)
• 如果我转到选项 2，我如何将 incoming 传递给 error？

下面是我的代码示例:

post ('/result') do 

  begin  
  @incoming = JSON.parse(request.body.read)

  //do something that causes an error
  rescue
     e = env['sinatra.error']
     url = request.url
     ip = request.ip

     @actlogpassblock = {  :message => e.message,
                        :path => url,
                        :ip => ip,
                        :timestamp => Time.new,
                        :type => "500",
                        :sub => "RES",
                        :payload => @incoming
                      }        
    action_log.insert(@actlogpassblock)
    status 500 
  end
end

error do
   status 500 
   e = env['sinatra.error']
   url = request.url
   ip = request.ip
   backtrace = "Application error\n#{e}\n#{e.backtrace.join("\n")}"

  @actlogpassblock = {  :message => e.message,
                        :path => url,
                        :ip => ip,
                        :timestamp => Time.new,
                        :type => "500",
                        :backtrace => backtrace
                      }        
  action_log.insert(@actlogpassblock)
  {:result => 'Ah Shucks! Something went wrong'}.to_json
end

Answer 1

If I stay with option 1, how do I prevent error from picking up the error (as it seems to be doing now)

根据文档:

The error handler is invoked any time an exception is raised from a route block...

但是，这仅适用于未捕获 异常。试试这个:

require 'sinatra'
set :show_exceptions, false

get '/' do
  begin
    raise ZeroDivisionError
  rescue ZeroDivisionError
    "rescue clause"
  end
end

error do
  "sinatra error handler" 
end

然后试试这个:

get '/' do
  raise ZeroDivisionError
end

error do
  "sinatra error handler" 
end

此外，您可以定制错误处理程序以仅捕获某些异常，从而避免某些异常，例如

error IndexError do ...

或

error MyCustomException do ...

或

error 400..510 do

但对于捕获所有版本:

error do

当路由 block 中发生未捕获的异常时，您不能阻止它执行...除非:

The error handlers will only be invoked, however, if both the Sinatra :raise_errors and :show_exceptions configuration options have been set to false...

:raise_errors defaults to true in the "test" environment and to false on other environments.

:show_exceptions value defaults to true in the "development" environment and to false on other environments

The author of Sintra has said: "This [behavior] is intentional. The idea is that error blocks will hide the issue and you usually don't want to do this in development mode.

https://github.com/sul-dlss/sdr-services-app/blob/master/Sinatra-error-handling.md

If I go to option 2, how do I pass incoming to error?

可以在错误 block 中看到在路由 block 内创建的@variable。试试这个:

require 'sinatra'
set :show_exceptions, false

get '/' do
  @incoming = "hello world"    #create @variable
  raise ZeroDivisionError
end

error ZeroDivisionError do
  @incoming                    #retrieve @variable
end

在浏览器中输入 url http://localhost:4567 后，您应该会在返回的网页上看到“hello world”。

之所以起作用，是因为 @variable 在创建 @variable 时将其自身附加到任何对象本身；同样，当调用 @variable 时，它​​会从当时是 self 的任何对象中检索出来。当 Sinatra 执行路由 block 或错误 block 时，它会将 self 设置为同一个对象。

选项 2 看起来不错，因为它将错误处理代码与应用程序代码分开。