Conquering a large JavaScript codebase

JavaScript was originally conceived to write little scripts that could add some interactivity to a web page. Today, it is used for increasingly large applications — in the browser, but also on the server, e.g. using node.js.
Cloud9 IDE is an Integrated Development Environment developed exclusively in JavaScript, both on the client and server-side, counting over 240,000 lines of JavaScript code. Managing a code base this large requires a good architecture, good solid code foundation as well as solid tools. During this talk I will describe the Cloud9 infrastructure as well as the techniques, libraries and tools we are developing to make it scale, and also how language analysis is helping us make sure that our code is rock-solid thoughout all our application.

Transcript

1. a large JavaScript codebase
   Conquering
   

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2. @sergimansilla
   

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6. Create
   Share Test
   Deploy
   Run/Debug
   

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7. The$easiest$way$to$create$Node.js$apps
   

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8. Ftp
   WebDAV
   Heroku
   Git
   Language Analysis
   Vim mode
   Run/Debug
   Cloud storage
   Revisions
   Search
   Collaboration
   Cloudfoundry
   Azure
   Testing
   CLI
   Bitbucket
   Plugins
   

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9. Pretty big app
   

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10. More than 1M lines
    (with semicolons)
    

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11. Of JavaScript
    

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12. Pure madness
    

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13. Why sparta madness?
    

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14. Javascript/Node.js
    make you more productive
    

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15. But they won’t help
    you through your growing pains
    

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16. What about
    some examples
    

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18. Why Node.JS?
    

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20. V8 JavaScript engine
    

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21. Bindings to libuv
    

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22. Best cross-platform I/O library
    

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23. API accessible from JavaScript
    

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24. Async I/O
    

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25. Async I/O is a big deal
    

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26. You can do things like this
    without blocking
    

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27. You can do things like this
    without blocking
    Loop$monkey,$loop!
    Write$a$‘.’$for$each$read$file
    Read$this$very$file
    

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29. You probably want
    something like this
    Read$this$very$file
    Write$a$‘.’$for$each$read$file
    Loop$monkey,$loop!
    Only$100$items$at$a$
    Dme,$thanks
    

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30. Never, ever, ever, EVER block
    

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32. In node, all APIs are
    asynchronous
    

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33. In node, all APIs are
    asynchronous?
    

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34. Getting a hash
    

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35. Getting a hash
    

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36. Getting a hash
    

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37. Getting a hash
    

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38. Profile before going live
    

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39. DTrace + node-stackvis
    http://blog.nodejs.org/2012/04/25/profiling-node-js/
    

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40. Embrace the
    paradigm
    

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41. Push processing
    to the client
    

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42. Use workers
    

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43. Use workers
    serialization < computation
    BUT only if
    

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44. Use workers
    worker.postMessage(...)
    Small objects only!
    

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45. Modularize your code
    

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46. Your application will fail
    

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47. Be prepared
    

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48. Architect
    github.com/c9/architect
    

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49. “A simple yet powerful plugin
    system for large-scale node
    applications”
    

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50. Isolation
    

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51. Security
    

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52. Providers / Consumers
    

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53. Advanced IPC
    between processes
    

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54. Sourcemint
    github.com/sourcemint/sm-npm
    

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55. Package manager that wraps
    package managers
    

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56. Understands any kind
    of dependency
    (npm, pip, git, zip...)
    

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57. Easy edit/publish
    

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58. Tooling matters
    

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59. Normal developers
    

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60. JavaScript Developer
    

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62. Tooling matters
    

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63. Tooling matters
    especially for JavaScript
    

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65. Use the power of...
    

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66. tatic
    

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67. program analysis
    

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69. Iterating using undeclared
    variable
    

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70. Warning: you are in an anonymous inner function
    with its own “this” pointer
    

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71. Did you mean length?
    

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72. “The most important thing I have done as
    a programmer in recent years is to
    aggressively pursue static code
    analysis.”
    John Carmack
    

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73. treehugger.js
    github.com/ajaxorg/treehugger
    

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74. “The jQuery of AST analysis.”
    

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75. What can you do with it?
    

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76. Low-level tooling
    

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77. Intelligent code completion
    

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78. Complex refactoring
    

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79. Automate everything
    

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80. Human error happens
    

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81. Human error happens
    ALL THE TIME
    

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82. Spend time on
    automation scripts
    

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83. Spend time on
    automation scripts
    It really pays off
    

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84. Happy coding!
    

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85. Questions?
    

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86. http://github.com/sergi
    @sergimansilla
    http://c9.io
    

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