Defacing Your Views

Deface is a gem to make targeted changes to views without altering the source file. It was developed by the Spree core team to help when multiple engines attempt to override the same view file.

DC Rug August 9, 2012

Transcript

1. DEFACING YOUR VIEWS Friday, August 10, 12
2. CHRIS MAR • Spree Core Team Member • github.com/cmar • @cmar • @spreecommerce • @spreeworks Friday, August 10, 12
3. PROBLEM? Friday, August 10, 12
4. MAIN RAILS APPLICATION Friday, August 10, 12
5. MAIN RAILS APPLICATION ENGINE #1 Friday, August 10, 12
6. MAIN RAILS APPLICATION ENGINE #1 Friday, August 10, 12
7. MAIN RAILS APPLICATION ENGINE #1 Friday, August 10, 12
8. MAIN RAILS APPLICATION ENGINE #1 ENGINE #2 Friday, August 10, 12
9. MAIN RAILS APPLICATION ENGINE #1 ENGINE #2 X PROBLEM! Friday, August 10, 12
10. MAIN RAILS APPLICATION ENGINE #1 ENGINE #2 Friday, August 10, 12
11. MAIN RAILS APPLICATION ENGINE #1 ENGINE #2 CHANGE Friday, August 10, 12
12. MAIN RAILS APPLICATION ENGINE #1 ENGINE #2 CHANGE CHANGE If there was only a gem for that! Friday, August 10, 12
13. Friday, August 10, 12
14. ORIGINAL ERB Friday, August 10, 12
15. ORIGINAL ERB DEFACE PRE-PARSER PSEUDO ERB XML Friday, August 10, 12
16. ORIGINAL ERB DEFACE PRE-PARSER PSEUDO ERB XML NOKOGIRI Friday, August 10, 12
17. ORIGINAL ERB DEFACE PRE-PARSER PSEUDO ERB XML NOKOGIRI PSEUDO ERB XML DEFACE OVERRIDES Friday, August 10, 12
18. ORIGINAL ERB DEFACE PRE-PARSER PSEUDO ERB XML NOKOGIRI PSEUDO ERB XML DEFACE OVERRIDES DEFACE POST-PARSER FINAL ERB Friday, August 10, 12
19. OVERIDES Friday, August 10, 12
20. spree/products/show TARGET Friday, August 10, 12
21. :insert_bottom => ‘div#thumbs’ ACTION Friday, August 10, 12
22. :text => ‘hello world!’ SOURCE Friday, August 10, 12
23. app/controllers app/models app/views app/overrides tweak_thumbs.override.rb OVERRIDES Friday, August 10, 12
24. Deface::Override.new(:virtual_path => "spree/products/show", :name => "tweak_thumbs", :insert_bottom => "div#thumbs", :text => %q{<span>Hello World</span>}) OVERRIDE Friday, August 10, 12
25. 1 2 3 4 5 6 7 8 <div id="product-images" data-hook="product_images"> <div id="main-image" data-hook> <%= render 'image' %> </div> <div id="thumbs" data-hook> <%= render 'thumbnails', :product => @product %> </div> </div> Deface::Override.new(:virtual_path => "spree/products/show", :name => "tweak_thumbs", :insert_bottom => "div#thumbs", :text => ‘<span>Hello World</span>’) 1 2 3 4 Friday, August 10, 12
26. 1 2 3 4 5 6 7 8 9 <div id="product-images" data-hook="product_images"> <div id="main-image" data-hook> <%= render 'image' %> </div> <div id="thumbnails" data-hook> <%= render 'thumbnails', :product => @product %> </div> </div> FINAL Friday, August 10, 12
27. 1 2 3 4 5 6 7 8 9 <div id="product-images" data-hook="product_images"> <div id="main-image" data-hook> <%= render 'image' %> </div> <div id="thumbnails" data-hook> <%= render 'thumbnails', :product => @product %> </div> </div> <span>Hello World</span> FINAL Friday, August 10, 12
28. DETAILS Friday, August 10, 12
29. MATCHERS • CSS3 selectors supported by Nokogiri • <% %> matched as code[erb-silent] • code[erb-loud]:contains(‘end‘) matches <%= end %> Friday, August 10, 12
30. ACTIONS • insert_(after, before, top, bottom) • remove • (replace, surround)_contents • (set, add_to, remove_from)_attributes Friday, August 10, 12
31. SOURCE • content to be inserted • erb • partials • text • HAML Friday, August 10, 12
32. Friday, August 10, 12
33. PRO TIPS Friday, August 10, 12
34. ADVANCED SELECTORS • range selections • cut & copy Friday, August 10, 12
35. ADVANCED • original hash • optionally throw exception • override sequencing Friday, August 10, 12
36. DSL • To override ‘app/views/posts/_post.html.erb’ • app/overrides/posts/_post/my_override.html.erb.deface <!-- insert_after 'h1' --> <h2>These robots are awesome.</h2> Friday, August 10, 12
37. PRODUCTION • rake deface:precompile • app/compiled_views • config.deface.disabled = true • rake deface:clean Friday, August 10, 12
38. RAKE • rake deface:get_result[path] • rake deface:test_selector[path, matcher] Friday, August 10, 12
39. deface.heroku.com Friday, August 10, 12
40. MAGIC ActionView::Template.class_eval do alias_method :initialize_without_deface, :initialize def initialize(source, identifier, handler, details) ... processed_source = Deface::Override.apply(source, details, true) ... initialize_without_deface(processed_source, identifier, handler, details) end end Friday, August 10, 12
41. GEM • gem ‘deface’ • github.com/railsdog/deface Friday, August 10, 12
42. Friday, August 10, 12
43. ROCKSTAR + NINJA + WIZARD jobs@spreecommerce.com must LOVE open source Friday, August 10, 12
44. Friday, August 10, 12
45. #RUBYLOCO • LOudoun COunty WFH + Ruby • Last Friday Lunch in Leesburg • @ruby_loco Friday, August 10, 12
46. QUESTIONS? Friday, August 10, 12