A Journey Into Feature Toggles - OSCON Austin 2017

Feature toggles (aka feature flags) are a set of patterns that enable dev teams to deliver features to users rapidly and safely. Pete Hodgson leads you on a journey with a dev team as they adopt feature toggles, covering what they are, why they're helpful, and how to use them successfully.

Transcript

1. Pete Hodgson OSCON Aus1n 2017 FEATURE TOGGLES a journey into
2. @ph1 #oscon Let me
 tell you
 a story
3. @ph1 #oscon Boy, that merge conflict we ran into sure was painful “
4. @ph1 #oscon master ! Sam's feature branch Jesse’s feature branch merge bomb based on: martinfowler.com/bliki/FeatureBranch.html
5. @ph1 #oscon avoiding the
 merge bombs
6. @ph1 #oscon Product Details Buy Related Products
7. @ph1 #oscon function relatedProducts(product){ // current implementation lives here }
8. @ph1 #oscon function old_relatedProducts(product){ // current implementation lives here } function new_relatedProducts(product){ // TODO: write a better // related products algorithm }
9. @ph1 #oscon function relatedProducts(product){ var useNewAlgorithm = false; if( useNewAlgorithm ){ return new_relatedProducts(product); }else{ return old_relatedProducts(product); } } function old_relatedProducts(product){ // current implementation lives here } function new_relatedProducts(product){ // TODO: write a better // related products algorithm }
10. @ph1 #oscon exis1ng implementa1on client
11. @ph1 #oscon exis1ng implementa1on new implementa1on client
12. @ph1 #oscon exis1ng implementa1on client half-finished new implementa1on
13. @ph1 #oscon exis1ng implementa1on client half-finished new implementa1on
14. @ph1 #oscon exis1ng implementa1on client half-finished new implementa1on
15. @ph1 #oscon exis1ng implementa1on client half-finished new implementa1on
16. @ph1 #oscon function relatedProducts(product){ var useNewAlgorithm = false; if( useNewAlgorithm ){ return new_relatedProducts(product); }else{ return old_relatedProducts(product); } } function old_relatedProducts(product){ // current implementation lives here } function new_relatedProducts(product){ // TODO: write a better // related products algorithm }
17. @ph1 #oscon function relatedProducts(product){ var useNewAlgorithm = false; if( useNewAlgorithm ){ return new_relatedProducts(product); }else{ return old_relatedProducts(product); } } function old_relatedProducts(product){ // current implementation lives here } function new_relatedProducts(product){ // TODO: write a better // related products algorithm } true;
18. @ph1 #oscon let’s get dynamic
19. @ph1 #oscon function relatedProducts(product){ var useNewAlgorithm = false; if( useNewAlgorithm ){ return new_relatedProducts(product); }else{ return old_relatedProducts(product); } }
20. @ph1 #oscon function relatedProducts(product){ if( featureEnabled(“use-new-related-products-algo”) ){ return new_relatedProducts(product); }else{ return old_relatedProducts(product); } }
21. @ph1 #oscon exis1ng implementa1on new implementa1on client
22. @ph1 #oscon exis1ng implementa1on new implementa1on client
23. @ph1 #oscon FEATURE TOGGLES
24. @ph1 #oscon FEATURE TOGGLES a journey into
25. @ph1 #oscon FLAGS BITS FLIPPERS FEATURE TOGGLES
26. @ph1 #oscon decoupling deployment from release
27. @ph1 #oscon it starts with
 merge conflicts
28. @ph1 #oscon back to
 the story...
29. @ph1 #oscon Canary
 Releases A/B Tests Kill Switches Beta Testers Premium
 Features
30. @ph1 #oscon 1me out!
31. @ph1 #oscon you keep using that word…
32. @ph1 #oscon choosing code paths at runLme
33. @ph1 #oscon client
34. @ph1 #oscon client
35. @ph1 #oscon treat different toggles differently
36. @ph1 #oscon Ops Toggles Permission Toggles Release Toggles Experiment Toggles
37. @ph1 #oscon longevity release toggles
 are around for days permissions toggles
 are around for years
38. @ph1 #oscon dynamism release toggles
 vary per deployment experiment toggles
 vary per request
39. @ph1 #oscon ownership release toggles ops toggles permission toggles experiment toggles owned by devs owned by ops owned by product
40. @ph1 #oscon toggle longevity
41. @ph1 #oscon function relatedProducts(product){ if( featureEnabled(“use-new-related-products-algo”) ){ return new_relatedProducts(product); }else{ return old_relatedProducts(product); } }
42. @ph1 #oscon if( featureEnabled(“use-new-related-products-algo”) ){ // do X }else{ // do Y } if( featureEnabled(“use-new-related-products-algo”) ){ // do X }else{ // do Y } if( featureEnabled(“use-new-related-products-algo”) ){ // do X }else{ // do Y } if( featureEnabled(“use-new-related-products-algo”) ){ // do X }else{ // do Y }
43. @ph1 #oscon toggle dynamism
44. @ph1 #oscon Product Details Buy Related Products
45. @ph1 #oscon Product Details BUY!
46. @ph1 #oscon function renderProductDetailsPage(){ if( featureEnabled(“show-related-products”) ){ renderProductDetailsSection({renderBuyButton:true}); renderRelatedProductSection(); }else{ renderProductDetailsSection({renderBuyButton:false}); renderReallyBigBuyButton(); } }
47. @ph1 #oscon function renderProductDetailsPage(){ if( featureEnabled(“show-related-products”) ){ renderProductDetailsSection({renderBuyButton:true}); renderRelatedProductSection(); }else{ renderProductDetailsSection({renderBuyButton:false}); renderReallyBigBuyButton(); } } function renderProductDetailsPage(){ if( featureEnabled(“show-related-products”,request) ){ renderProductDetailsSection({renderBuyButton:true}); renderRelatedProductSection(); }else{ renderProductDetailsSection({renderBuyButton:false}); renderReallyBigBuyButton(); } }
48. @ph1 #oscon toggle configuraLon sta1c dynamic
49. @ph1 #oscon toggle configuraLon Hard-coded
 in source config baked
 into deployment parameterized
 config config in
 the app DB distributed config
 (e.g. Consul, ZooKeeper) sta1c dynamic
50. @ph1 #oscon ? sta1c dynamic
51. @ph1 #oscon make toggle
 configuraLon observable
52. @ph1 #oscon allow overriding configuraLon for tesLng
53. @ph1 #oscon advice from the trenches
54. @ph1 #oscon toggles aren’t free
55. @ph1 #oscon tesLng toggled code
 isn’t easy
56. @ph1 #oscon toggles help you 
 go faster
57. FEATURE TOGGLES your journey into @ph1 #oscon
58. @ph1 #oscon @ph1 thepete.net mar1nfowler.com/ar1cles/feature-toggles.html thanks!