Large Scale Modularization

Ever wonder what it takes to fully modularize a large application and begin working on instant apps? Wonder no more, in this talk we review how we tackled the problem of modularization, and package separation within the large Groupon Android App.

Transcript

1. Modularizing a Large Code Base WHY AND HOW 1 Slides at : http://tiny.cc/grpnMod
2. ABOUT US ERIK KAMP AOLEI ZHANG Android Dev @GRN Android Dev @GRN ekamp aolei
3. 3 We need an Instant App! It’s taking too long to build! LemonAide - Good For the Soul!
4. 4 *&^*$*%* LemonAide - Good For the Soul!
5. 5 LemonAide - Good For the Soul!
6. WHY MODULARIZE? WHY FIX IT IF IT AIN’T BROKE 6
7. BUILD SPEED 7
8. Why Modularize - BUILD SPEED 8 Entire application Recompiles Recompile Class Update
9. Why Modularize - BUILD SPEED 9 Compile Avoidance Calorie Tracker Module class Recompiles Users Module Depends on Recipes Module
10. Why Modularize - BUILD SPEED 10 Potential Problem with Multiple Modules variant Checkout Calorie Tracker Main Recipes Our Builds are taking longer!!
11. 11 GAP 3 variant-aware dependency management
12. Why Modularize - BUILD SPEED 12 Potential Problem with Multiple Modules variant Much Better!
13. Why Modularize - BUILD SPEED 13 Remote Build Cache “Faster builds with build cache.” Build cache | Gradle Inc., Gradle, gradle.com/build-cache.
14. BUT WAIT THERE’S MORE! 14
15. Why Modularize - CLEANLINESS - HIDDEN BENEFIT 15 Before After Checkout Main Recipes News
16. 16 INSTANT APPS
17. METHODOLOGY HOW WE GOT STARTED 17
18. Methodology - COMMUNICATION 18 • Negotiation • New Norms Experiment Communication Scale Up Communication
19. Methodology - COMMUNICATING 19 Hosting Meetings Speaking With Managers Business Reasoning • Conveying the Big Picture • How will this help my team? • How will this grow the business?
20. Methodology - AGREEING ON A STRUCTURE 20 How are we going to layer the packages? • Feature-wise • Team-wise • Type / Layered
21. Methodology - AGREEING ON A STRUCTURE 21 Team Based SUGAR TEAM RECIPES CALORIE TRACKER FRAGMENTS ACTIVITIES FRAGMENTS ACTIVITIES CALORIE TRACKER LEMON TEAM SUGAR TEAM Feature Based
22. Methodology - EXPERIMENTING 22 Very little information Highly Coupled Code Navigation • Scholarly Resources • Blog Posts • Difficulties separating out • Automation • Activities • Intent Builders
23. Methodology - EXPERIMENT 23 • Module creation • Research • Negotiation • New Norms Experiment Experiment Scale Up Communication
24. Methodology - SCALING UP 24 Peer Programming Two way communication • Guiding • Convincing • Optimization • “Real World”
25. Methodology - SCALE UP 25 • Module creation • Research • Negotiation • New Norms Experiment Scale Up • Who to include • How quickly to intro changes Scale Up Communication
26. Methodology - COMMUNICATING - MODULE REPORT 26
27. Techniques Avoiding Grey Hairs 27
28. Techniques - DEPENDENCIES 28
29. Techniques - DEPENDENCY GRAPH 29 .class files Dot file Dependency graph classcycle* to PNG** ** https://www.graphviz.org/ * http://classycle.sourceforge.net/
30. Techniques - DEPENDENCY GRAPH 30
31. 31 Techniques - Cycles
32. Techniques - CYCLES 32 GlutenFree Ingredients
33. Techniques - CYCLES - Removal 33 GlutenFree Ingredients Supply
34. Techniques - CYCLES - DETECTION 34 FindBugs - Cycle Detection Plugin • Comprehensive Report • Already present in our project
35. Techniques - CYCLES - FindBugs - Report 35 Summary: Input file is "findCyclesRelease.xml” 63 cycles detected. They are white-listed in white-list.json
36. Techniques - CYCLES - DETECTION 36 Unused Classes
37. Techniques - CYCLES - DETECTION 37 Most Used Classes
38. Techniques - CYCLES - DETECTION 38 Least Used Classes
39. REGRESSION PREVENTION 39
40. Techniques - REGRESSION PREVENTION 40 • Prevent growth of deprecated packages Webhooks Scripts • Prevent new cycle creation • Monitor module dependencies
41. IDE SUPPORT 41
42. Techniques - AS3 MODULARIZE 42 Summary of Dependencies
43. Tooling - AS3 MODULARIZE 43 Move and Refactor
44. Techniques - AS3 MODULARIZE 44 Oh no...
45. INTERFACE TECHNIQUE 45
46. Techniques - INTERFACE TECHNIQUE 46 Main Module Main Module Ingred. GlutenFree GF Ingred.
47. Techniques - INTERFACE TECHNIQUE 47 Main Module Recipe Module GlutenFree Ingredients Interface
48. Tooling - INTERFACE TECHNIQUE 48 In Recipe Module: define the interface public interface Recipe_Ingredients { // methods needed by new module boolean isGlutenFree(); } In Main Module public class Ingredients { boolean isGlutenFree() { // code that implements the method } } : implement the interface implements Recipe_Ingredients { @Override
49. Tooling - INTERFACE TECHNIQUE 49 In Main Module: Glue them together ... { public RecipeInterfaceBinder() { bind(Recipe_Ingredients).to(Ingredients); } }
50. Techniques - INTERFACE TECHNIQUE 50 • Quickly Move classes Benefits • Exposes dependencies • Feature modules
51. Techniques - INTERFACE TECHNIQUE 51 Drawbacks • Highly coupled classes are not moved • Compile modules vs instant app modules • Boilerplate per module
52. Techniques - IN SUMMARY 52 • Dependency Graph • Cycles Detection & Removal • IDE Support • Regression Prevention • Interface Technique
53. MOVING FORWARD COLLABORATION / FUTURE PLANS / WORK 53
54. Questions? 54 Slides at : http://tiny.cc/grpnMod