Supercharging project health check

go beyond the usual practices

Transcript

1. Super charging project health check go beyond the usual practices David Horvath Lead iOS Developer @egyes Swifters meetup 2021 March
2. digital agency ┘ Lot of different projects throughout the years ┘ Project handovers ┘ Code audits
3. issues ┘ Tons of things to check ┘ Lot of different approaches ┘ Require a lot of time (it’s never enough) ┘ Huge projects - Potentially overlooked problems
4. goals ┘ Find the most crucial issues in the shortest time ┘ Be more efficient in gaining insights ┘ Efficiently identify the changes to the code which provide the most value
5. useful when ┘ You have to do a project audit ┘ You join a new project ┘ You just want to get new insights into your current project ┘ You want to refactor or rewrite ∷ You can show these findings to your client/boss/lead
6. process ┘ Checking git reports ∷ Interesting details about the project ∷ Gitlab / Github - GitStats(SourceForge)
7. git reports
8. process ┘ Checking git reports ∷ Interesting details about the project ∷ Gitlab / Github - GitStats ┘ Checking project size
9. cloc
10. process ┘ Checking git reports ∷ Interesting details about the project ∷ Gitlab / Github - GitStats ┘ Checking project size ∷ Cloc ┘ Open the project and build it ∷ High-level overview
11. high- level overview ┘ File structure ┘ Naming conventions ┘ Modularization ┘ Dependencies (spm, pod, carthage) ┘ UI (code / xib / storyboards) ┘ Architecture ┘ Compile time ┘ Xcode memory graph
12. process ┘ Checking git reports ∷ Interesting details about the project ∷ Gitlab / Github - GitStats ┘ Checking project size ∷ Cloc ┘ Open the project and build it ∷ Highlevel overview ┘ Visualize class dependencies
13. dependency visualizer
14. dependency visualizer
15. process ┘ Checking git reports ∷ Interesting details about the project ∷ Gitlab / Github - GitStats ┘ Checking project size ∷ Cloc ┘ Open the project and build it ∷ Highlevel overview ┘ Visualize class dependencies ∷ objc-dependency-visualizer ┘ Static code analysis ∷ Cyclomatic complexity ∷ Code duplication
16. lizard
17. lizard
18. process ┘ Checking git reports ∷ Interesting details about the project ∷ Gitlab / Github - GitStats ┘ Checking project size ∷ Cloc ┘ Visualize class dependencies ∷ objc-dependency-visualizer ┘ Checking cyclomatic complexity ∷ Lizard ┘ Static code analysis ∷ Cyclomatic complexity ∷ Code duplication ∷ Lizard / CPD ┘ Checking dead code
19. periphery
20. process ┘ Checking git reports ∷ Interesting details about the project ∷ Gitlab / Github - GitStats ┘ Checking project size ∷ Cloc ┘ Visualize class dependencies ∷ objc-dependency-visualizer ┘ Checking cyclomatic complexity ∷ Lizard ┘ Static code analysis ∷ Cyclomatic complexity ∷ Code duplication ∷ Lizard / CPD ┘ Checking dead code ∷ Periphery
21. quick process summary ┘ We have a lot of information about the project already ∷ High-level overview ∷ Data about the project size and age ∷ List of complexities ∷ List of duplication ∷ Duplication rate ∷ List of unused codes ∷ Nice visualization of the class dependencies ┘ It only took a few hours
22. so what’s new?
23. problems ┘ We spend so much time looking at the current state of the code that we forget its history ┘ Its hard to understand large-scale complex systems by looking at a snapshot of the code ┘ We miss a lot of information
24. where can we find more info?
25. version control systems ┘ We use it to keep track of the project history ┘ Rarely think about the insights we can get by mining data from it ┘ We can learn about the environment ┘ We can learn about how we work ┘ Predict which parts of the code have the most defects ┘ Find the code that matters most for maintenance ┘ Information is real power
26. git log
27. code maat ┘ Command line tool ┘ To mine and analyze data from version control systems ┘ It supports different version control systems ∷ git, svn, perforce, tfs, mercurial ┘ We can use it to detect hotspots ┘ We can use it to detect architectural problems ┘ And so much more
28. generate maat readable log
29. summary
30. Hotspots ┘ Hotspots are your guide to improvements and refactorings ┘ Research has shown that frequent changes to complex code generally indicate declining quality ┘ Over time our development focus shifts so the hotspots will also shift ┘ Hotspots can predict defects very well ┘ We can find them at the intersection of complexity and effort
31. revisions (changes)
32. cloc --by-file
33. cloc --by-file
34. merge them for hotspots
37. Coupling ┘ We can detect which files are changing together most of the time ┘ Detect architectural / design issues ┘ Explicit coupling ∷ What tend to change together (screen + vm) ┘ Temporal coupling ∷ This is what we are looking for ∷ Can be false positives (service + test) ∷ Can be serious design problem ∷ Can be copy-paste
38. sum of coupling
39. coupling by files
40. false positives
41. true problems
42. path transformation
43. transformed coupling info
44. transformed coupling info
45. other features ┘ Complexity trends ∷ Evaluate growth patterns ∷ Analyze complexity trends ┘ Discover organizational metrics ∷ Social problems ∷ Evaluate communication costs ∷ Build knowledge map ∷ Visualize knowledge loss ┘ Code chur ∷ Predict defects ∷ Discover process loss from code
46. process summary ┘ High-level overview of the codebase ┘ List of complexities ┘ List of duplications ┘ List of unused codes ┘ List of hotspots ┘ List of problematic dependencies
47. goals ┘ ✅ Find the most crucial issues in the shortest time ┘ ✅ Be more efficient in gaining insights ┘ ✅ Efficiently identify the changes to the code which provide the most value
48. suggesti ons ┘ Run these analyses every few months ┘ Can be part of CI/CD release process ┘ Talk the findings through with your team ┘ Read Adam Tornhill’s book to learn more: Your Code as a Crime Scene
49. sum up ┘ With the right tools you can quickly and efficiently spot problems ┘ You can use your version control systems to have more information about your project ┘ By mining data from it, you can get a deeper understanding of your design / architectural problems ┘ With the right data you can back your refactoring/ rewrite proposals ┘ Focusing on the right things early you can save a lot of maintenance cost
50. thank you for your attention David Horvath Lead iOS Developer @egyes
51. tools ┘ GitStats ∷ http://gitstats.sourceforge.net ┘ Cloc ∷ https://github.com/AlDanial/cloc ┘ Lizard ∷ https://github.com/terryyin/lizard ┘ Periphery ∷ https://github.com/peripheryapp/periphery ┘ Objc-dependency-visualizer ∷ https://github.com/PaulTaykalo/objc-dependency-visualizer ┘ Swift-dependency-visualizer ∷ https://github.com/PrzemyslawCholewaDev/swift-dependency- visualizer ┘ Code maat ∷ https://github.com/adamtornhill/code-maat