我在我的Rails应用程序中使用Memcached作为Object Store,我在其中存储了memcached中User对象的搜索结果
现在,当我获取数据时,我得到了Memcached Undefined Class / Module Error.我在这个博客中找到了解决这个问题的方法
http://www.philsergi.com/2007/06/rails-memcached-undefinded-classmodule.html
before_filter :preload_models
def preload_models
Model1
Model2
end
建议事先预装模型.我想知道是否有一个更优雅的解决方案来解决这个问题,并且使用预加载技术有任何缺点.
提前致谢
解决方法
我也有这个问题,我想我想出了一个很好的解决方案.
module ActiveSupport
module Cache
class MemCacheStore
# Fetching the entry from memcached
# For some reason sometimes the classes are undefined
# First rescue: trying to constantize the class and try again.
# Second rescue,reload all the models
# Else raise the exception
def fetch(key,options = {})
retries = 2
begin
super
rescue ArgumentError,NameError => exc
if retries == 2
if exc.message.match /undefined class\/module (.+)$/
$1.constantize
end
retries -= 1
retry
elsif retries == 1
retries -= 1
preload_models
retry
else
raise exc
end
end
end
private
# There are errors sometimes like: undefined class module ClassName.
# With this method we re-load every model
def preload_models
#we need to reference the classes here so if coming from cache Marshal.load will find them
ActiveRecord::Base.connection.tables.each do |model|
begin
"#{model.classify}".constantize
rescue Exception
end
end
end
end
end
end
