我一直在将 Rails 2 应用程序升级到 Rails 3.2.13,当我尝试启用缓存时遇到问题。缓存在 Rails 2 中工作,我使用的是相同版本的 Ruby - 1.8.7。我不确定它是否相关,但我正在 OSX 上开发。
调用 expire_fragment 时,从 ActionController::Caching::Fragments 类抛出错误。expire_fragment 调用 fragment_cache_key ,其中包含:
ActiveSupport::Cache.expand_cache_key(key.is_a?(Hash) ? url_for(key).split("://").last : key, :views)
对 url_for 的调用引发了此错误
2013-07-10T14:40:50.430137+01:00 FATAL
RuntimeError (In order to use #url_for, you must include routing helpers explicitly. For instance, `include Rails.application.routes.url_helpers):
lib/bio_catalogue/cache_helper.rb:175:in `expire_fragment'
lib/bio_catalogue/cache_helper.rb:181:in `expire_service_index_tag_cloud'
app/observers/annotation_observer.rb:33:in `expire_caches'
app/observers/annotation_observer.rb:12:in `after_create'
app/controllers/annotations_controller.rb:140:in `create_inline'
这是进一步延伸的回溯:
freya.2235 actionpack (3.2.13) lib/abstract_controller/url_for.rb:14:in `_routes'
freya.2235 actionpack (3.2.13) lib/action_dispatch/routing/url_for.rb:148:in `url_=
freya.2235 for'
freya.2235 actionpack (3.2.13) lib/action_controller/caching/fragments.rb:53:in `f=
freya.2235 ragment_cache_key'
freya.2235 actionpack (3.2.13) lib/action_controller/caching/fragments.rb:112:in `=
freya.2235 expire_fragment'
freya.2235 lib/bio_catalogue/cache_helper.rb:175:in `expire_fragment'
freya.2235 lib/bio_catalogue/cache_helper.rb:181:in `expire_service_index_tag_clou=
freya.2235 d'
freya.2235 app/observers/annotation_observer.rb:33:in `expire_caches'
freya.2235 app/observers/annotation_observer.rb:12:in `after_create'
freya.2235 activemodel (3.2.13) lib/active_model/observing.rb:231:in `send'
freya.2235 activemodel (3.2.13) lib/active_model/observing.rb:231:in `update'
freya.2235 activerecord (3.2.13) lib/active_record/observer.rb:114:in `_notify_ann=
freya.2235 otation_observer_for_after_create'
自然,我尝试在调用 expire_fragment 的类中包含 Rails.application.routes.url_helpers 但无济于事,因为错误来自 ActionController 模块。ActionController::Base 已经包含了 UrlFor 模块,所以我的问题是:为什么包含 UrlFor 的模块类会在应该能够使用 url_for 的情况下引发错误,要求包含 url_helpers?