Denis Radin - "Applying NASA coding guidelines to JavaScript or airspace is closer than you may think"
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The document discusses NASA code guidelines that can be applied to JavaScript development. It outlines 10 rules for writing reliable JavaScript code, including doing one thing per function, limiting control flow constructs, avoiding dynamic memory allocation, adding assertions, limiting scope, and compiling with all warnings enabled. The guidelines are presented alongside images related to space exploration and aviation to illustrate the importance of writing stable code for critical systems.
Denis Radin - "Applying NASA coding guidelines to JavaScript or airspace is closer than you may think"
- 2. Applying NASA code guidelines to JavaScript Airspace is closer than you may think Europa`s surface
- 4. The universe respects unification Planets shape, the laws of physics, and star system as a unit are constant everywhere Large Magellanic Cloud
- 5. “Unification — effective method to decrease diversity. Aim for unification is to place elements in particular order building strict system which is comfortable to use.” (c) Wikipedia Rosetta`s detination comet
- 6. It can be hard to distinguish them without being an expert There are sixtillions of standardized units... Milky Way, Salamnca, Spain
- 7. Unification never stops The same works for engineering ISS expedition 42 return
- 8. Diversity decreases since only best solutions survive... Is it a Boeing or Airbus?
- 9. Can you distinguish them at all? I bet you can not because of unification...
- 10. But such a common thing as UI definition is not standardized yet We develop software for 60 years Souyz space ship docks ISS
- 12. All UIs will be unified All planets are round Timelapse taken from ISS
- 13. Let`s guess... Standard? Voyager golden disks
- 14. Unification, reliability, accessability Why HTML for flight instruments? Bombardier Q400 electronic dashboard
- 15. Highly valuable in the age of drones Network accessibility MQ-1 Predator
- 16. Decreases development cost standardizing development flow and technologies stack Unification Work on NASA's InSight Lander
- 17. Browser is a GUI rendering system tested by billions users daily Reliablility NASA's Mission Control Center
- 18. Possibility to establish competitive UI components (flight instruments) market Components market Mir station modules scheme
- 19. And first ever flight using HTML/JS for displaying flight information First HTML/JS flight instrument Diamond aircraft DA40
- 22. ● Resources consuming efficiency ● Memory leaks ● GPU accelerated path ● Alternative rendering methods (Canvas, WebGL) Pitfalls?
- 23. Most likely because of your expectations from JS developers Scared flying JS driven airplane?
- 24. Trust is based on expectations on what is normal for JS This is all about trust
- 25. Let`s have a look at Jet Propulsion Laboratory More guidelines? JPL HQ
- 26. Can your JavaScript do this? Voyager: 36 years without bugs Voyager probe CGI
- 28. Performance and stability are priorities
- 29. Month without a reset ?
- 30. Code guidelines to the rescue...
- 31. No function should be longer than what can be printed on a single sheet of paper Rule #1 Sunrise on Saturn photo by Cassini probe, JPL
- 32. MARGARET HAMILTON next to printed source code of Apollo mission
- 33. Long functions: less readable, not reusable, harder to test, harder to refactor Rule #1 - Do one thing Sunrise on Saturn photo by Cassini probe, JPL
- 34. makeCoffeeAndCookEgg(){ let teapot = new Teapot(); let cup = new Cup(); let pan = new Pan(); let egg = new Egg(); teapot.on().then(teapot.fill.bind(cup)); pan.on() .then(egg.breake) .then(egg.fill.bind(cup)); } Rule #1 - Readibility Sunrise on Saturn photo by Cassini probe, JPL makeCoffeeAndCookEgg(){ makeCoffee(); cookEgg(); } makeCoffeeAndDoToast(){ makeCoffee(); doToast(); }
- 35. makeCoffeeAndCookEgg(){ let teapot = new Teapot(); let cup = new Cup(); let pan = new Pan(); let egg = new Egg(); teapot.on().then(teapot.fill.bind(cup)); pan.on() .then(egg.breake) .then(egg.fill.bind(cup)); } Rule #1 - Reusability Sunrise on Saturn photo by Cassini probe, JPL makeCoffeeAndCookEgg(){ makeCoffee(); cookEgg(); }
- 36. makeCoffeeAndCookEgg(){ let teapot = new Teapot(); let cup = new Cup(); let pan = new Pan(); let egg = new Egg(); teapot.on().then(teapot.fill.bind(cup)); pan.on() .then(egg.breake) .then(egg.fill.bind(cup)); } Rule #1 - Easy to refactor Sunrise on Saturn photo by Cassini probe, JPL makeCoffeeAndCookEggAfter(){ makeCoffee().then(cookEgg); }
- 37. Long functions: less readable, not reusable, harder to test, harder to refactor Rule #1 - Do one thing Sunrise on Saturn photo by Cassini probe, JPL
- 38. Restrict all code to very simple control flow constructs – do not use goto statements and direct or indirect recursion Rule #2 Mars, photo by Opportunity mission, JPL
- 39. Restrict all code to very simple control flow constructs – do not use goto statements and direct or indirect recursion Rule #2 - Predictability Mars, photo by Opportunity mission, JPL
- 40. ● If you want to write reliable code – drop to write cool one and write predictable ● Define coding standard and follow it ● Use code analyzers to reduce chance for defect: ESLint + whole lot of plugins, presets ● Collect metrics: SonarQube, Plato ● Analyze types with Flow/ Closure Tools / TypeScript Rule #2 - Predictability
- 41. Do not use dynamic memory allocation after initialization Rule #3 Ceres, photo JPL
- 42. GC might become your enemy Rule #3 - Respect RAM Ceres, photo JPL
- 43. DevTools / Timeline Measure Ceres, photo JPL
- 44. DevTools / Profile / Take heap snapshot Compare Ceres, photo JPL
- 45. ● Manage your variables with respect. Declare at the top of scope to increase visibility, ESLint vars-on-top. Sort for predictability sort-vars ● Watch for memory leaks, clean listeners and variables when not needed anymore ● ESLint no-unused-vars ● Switch JavaScript to static memory allocation mode via object pooling Rule #3 - Respect RAM
- 46. No new objects in run time. const pool = createObjectsPool(256); let object = pool.getObject(); pool.releaseObject(object); Object pooling? Ceres, photo JPL
- 47. All loops must have a fixed upper-bound Rule #4 Sunset at IIS
- 48. The assertion density of the code should average to a minimum of two assertions per function Rule #5 Jupiter`s eye
- 49. The assertion density of the code should average to a minimum of two assertions per function Rule #5 - Test well Jupiter`s eye
- 50. ● Higher tests density is less defects you get. Minimal amount of tests is 2 per function ● Watch for anomalies in system state during run time. Generate and handle errors in case of critical failures ● Measure coverage but be aware, 100% coverage does not necessarily mean you have well tested code Rule #5 - Test well
- 51. Data objects must be declared at the smallest possible level of scope Rule #6 City Lights of the Coast of India and the Maldives
- 52. Mutable shared state decreases predictability, testability since any part of system can write there without notyfing the rest Rule #6 - No shared state City Lights of the Coast of India and the Maldives
- 53. ESLint pureness plugin Rule #6 - No shared state City Lights of the Coast of India and the Maldives
- 54. The return value of non-void functions must be checked by each calling function, and the validity of parameters must be checked inside each function Rule #7 Young stars in NGC 7822
- 55. The use of the preprocessor must be limited to the inclusion of header files and simple macro definitions Rule #8 On Churyumov–Gerasimenko comet
- 56. Nice to know when using transpilers Performance of ES6 features relative to the ES5 The cost of transpiling ES2015 Falcon9 OG2 launch
- 57. The use of pointers should be restricted. Specifically, no more than one level of dereferencing is allowed. Function pointers are not permitted Rule #9 Interstellar dust
- 58. Dog.body.legs.run(); vs Dog.run(); Rule #9 - LoD Interstellar dust
- 59. Object1.object2.object3.method(); vs const object3 = Object1.object2.object3; object3.method(); Rule #9 - Call chains Interstellar dust
- 60. All code must be compiled, from the first day of development, with all compiler warnings enabled Rule #10 MyCn18: An Hourglass Planetary Nebula
- 61. All code must be compiled, from the first day of development, with all compiler warnings enabled Rule #10 - Keep green MyCn18: An Hourglass Planetary Nebula
- 62. What if we are already fu**ed up? Rule #10 - If red? MyCn18: An Hourglass Planetary Nebula
- 63. Do not panic. Simply, prioritize, refactor and add tests piece by piece. Rule #10 - If red? MyCn18: An Hourglass Planetary Nebula
- 64. Big step for web platform to be perceived as reliable Small step for developers but...
- 65. But still, why not HTML/JS for instruments? Ok, not that far yet... Eurofighter maneuvering
- 66. But still, why not HTML/JS for instruments? Ok, not that far yet... SU-30 take-off
- 67. But still, why not HTML/JS for instruments? Ok, not that far yet... EFIS displays
- 68. what about ships? And ...