ruby-on-rails - 如何处理来自 gem 的异常

Question

我正在调用方法 url_for gem aws-s3 , 它会抛出 MissingCredentialsError < StandardError .我怎样才能从 url_for 的类(class)中拯救它？叫做？我知道缺少凭据问题的解决方案，但我想知道如何处理异常。试过这个但没有运气:

begin
  ... code that get the error...
rescue MissingCredentialsError
  a = "THIS IS AN ERROR"
end

当我运行我的测试时，它遇到了这个错误:

ActionView::Template::Error: uninitialized constant Receipt::MissingCredentialsError

Answer 1

捕获错误时更具体:

begin
  # code that get the error
rescue AWS::Errors::MissingCredentialsError => e
  # code that handles the exception
end