fresh_when in ruby not working with xml rendering
- by Guilherme Silveira
While trying to implement support for conditional GETting in a rest system, we have come across the fresh_when and stale? methods.
The following code works fine with 304 and not further rendering:
if stale?(:etag = resource, :last_modified = resource.updated_at.utc)
respond_to do |format|
format.html # show.html.erb
}
end
end
But accessing 1.xml will try to render the resource twice:
if stale?(:etag => resource, :last_modified => resource.updated_at.utc)
respond_to do |format|
format.html # show.html.erb
format.xml {
render :xml => @order.to_xml(:controller => self, :except => [:paid_at])
}
end
end
The error message:
ActionController::DoubleRenderError in OrdersController#show
Can only render or redirect once per action
RAILS_ROOT: /Users/guilherme/Documents/ruby/restfulie-test
Application Trace | Framework Trace | Full Trace
/Library/Ruby/Gems/1.8/gems/actionpack-2.3.4/lib/action_controller/base.rb:900:in render_without_benchmark'
/Library/Ruby/Gems/1.8/gems/actionpack-2.3.4/lib/action_controller/benchmarking.rb:51:in render'
/Library/Ruby/Gems/1.8/gems/activesupport-2.3.4/lib/active_support/core_ext/benchmark.rb:17:in ms'
/Library/Ruby/Gems/1.8/gems/activesupport-2.3.4/lib/active_support/core_ext/benchmark.rb:10:in realtime'
/Library/Ruby/Gems/1.8/gems/activesupport-2.3.4/lib/active_support/core_ext/benchmark.rb:17:in ms'
/Library/Ruby/Gems/1.8/gems/actionpack-2.3.4/lib/action_controller/benchmarking.rb:51:in render'
/Library/Ruby/Gems/1.8/gems/actionpack-2.3.4/lib/action_controller/base.rb:1331:in send'
/Library/Ruby/Gems/1.8/gems/actionpack-2.3.4/lib/action_controller/base.rb:1331:in perform_action_without_filters'
/Library/Ruby/Gems/1.8/gems/actionpack-2.3.4/lib/action_controller/filters.rb:617:in call_filters'
/Library/Ruby/Gems/1.8/gems/actionpack-2.3.4/lib/action_controller/filters.rb:610:in perform_action_without_benchmark'
/Library/Ruby/Gems/1.8/gems/actionpack-2.3.4/lib/action_controller/benchmarking.rb:68:in perform_action_without_rescue'
/Library/Ruby/Gems/1.8/gems/activesupport-2.3.4/lib/active_support/core_ext/benchmark.rb:17:in ms'
/Library/Ruby/Gems/1.8/gems/activesupport-2.3.4/lib/active_support/core_ext/benchmark.rb:10:in realtime'
/Library/Ruby/Gems/1.8/gems/activesupport-2.3.4/lib/active_support/core_ext/benchmark.rb:17:in ms'
/Library/Ruby/Gems/1.8/gems/actionpack-2.3.4/lib/action_controller/benchmarking.rb:68:in perform_action_without_rescue'
/Library/Ruby/Gems/1.8/gems/actionpack-2.3.4/lib/action_controller/rescue.rb:160:in perform_action_without_flash'
/Library/Ruby/Gems/1.8/gems/actionpack-2.3.4/lib/action_controller/flash.rb:146:in perform_action'
/Library/Ruby/Gems/1.8/gems/actionpack-2.3.4/lib/action_controller/base.rb:532:in send'
/Library/Ruby/Gems/1.8/gems/actionpack-2.3.4/lib/action_controller/base.rb:532:in process_without_filters'
/Library/Ruby/Gems/1.8/gems/actionpack-2.3.4/lib/action_controller/filters.rb:606:in process'
/Library/Ruby/Gems/1.8/gems/actionpack-2.3.4/lib/action_controller/base.rb:391:in process'
/Library/Ruby/Gems/1.8/gems/actionpack-2.3.4/lib/action_controller/base.rb:386:in call'
/Library/Ruby/Gems/1.8/gems/actionpack-2.3.4/lib/action_controller/routing/route_set.rb:437:in `call'
Any suggestions?
Regards
