RailsConf 2022 Keynote

This is my RailsConf 2022 keynote

Transcript

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2. RailsConf 2022
   It's been a minute!
   

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3. PORTLAND
   

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9. Couch
   Glisan
   

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11. 3 YEARS!
    

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12. #FridayHug
    

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13. 🇺🇦🇺🇦🇺🇦
    

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16. RIP Little Buddy 😭
    

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18. ~5 Photos / Day 🤣
    

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25. https://www.youtube.com/
    TenderlovesCoolStuff
    Subscribe
    

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26. Tenderlove's Cool Stuff
    

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28. ˑˑˑˑˑ
    
    
    0 Stars: Do Not Recommend
    

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29. 💨
    

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30. View Slide

31. JIT: Generate Machine Code at
    Runtime
    

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32. Machine Code:
    
    
    Sequence of Bytes
    

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33. Ruby:
    
    
    Can Make a Sequence of Bytes
    ✅
    

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34. 🤔 Pure Ruby JIT? 🤔
    

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35. Yes! Yes, we can.
    

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36. https://github.com/tenderlove/tenderjit
    

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37. TenderJIT
    

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38. TenderJIT
    

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39. "Just because you can, doesn't
    mean you should!"
    

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40. Analog Terminal Bell
    https://analogterminalbell.com
    

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41. Professional Software
    Development
    

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43. Apple M1: AArch64
    

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44. x86_64 Only
    

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45. LeJIT JITs
    

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46. AArch64 Gem
    https://github.com/tenderlove/aarch64
    

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47. AArch64 Example
    JIT a function that returns 0xF00DCAFE
    $ gel exec ruby test.rb
    
    
    "f00dcafe"
    Terminal Output
    require "aarch64"
    
    
    require "jit_buffer"
    
    
    # create a JIT buffer
    
    
    jit_buffer = JITBuffer.new 4096
    
    
    asm = AArch64::Assembler.new
    
    
    # Make some instructions
    
    
    asm.pretty do
    
    
    asm.movz x0, 0xCAFE
    
    
    asm.movk x0, 0xF00D, lsl(16)
    
    
    asm.ret
    
    
    end
    
    
    # Write the instructions to a JIT buffer
    
    
    jit_buffer.writeable!
    
    
    asm.write_to jit_buffer
    
    
    jit_buffer.executable!
    
    
    # Execute the JIT buffer
    
    
    p jit_buffer.to_function([], -Fiddle::TYPE_INT).call.to_s(16) #
    => f00dcafe
    JIT Code
    

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48. AArch64 Example
    JIT a function that returns 0xF00DCAFE
    $ gel exec ruby test.rb
    
    
    "f00dcafe"
    Terminal Output
    asm = AArch64::Assembler.new
    
    
    # Make some instructions
    
    
    asm.pretty do
    
    
    asm.movz x0, 0xCAFE
    
    
    asm.movk x0, 0xF00D, lsl(16)
    
    
    asm.ret
    
    
    end
    JIT Code
    

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49. Not Amateur Enough
    

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50. Extremely Amateur
    

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51. AArch64 Example
    JIT a function that returns 0xF00DCAFE
    $ gel exec ruby test.rb
    
    
    "f00dcafe"
    Terminal Output
    require "aarch64"
    
    
    require "jit_buffer"
    
    
    # create a JIT buffer
    
    
    jit_buffer = JITBuffer.new 4096
    
    
    asm = AArch64::Assembler.new
    
    
    # Make some instructions
    
    
    asm.pretty do
    
    
    asm.movz x0, 0xCAFE
    
    
    asm.movk x0, 0xF00D, lsl(16)
    
    
    asm.ret
    
    
    end
    
    
    # Write the instructions to a JIT buffer
    
    
    jit_buffer.writeable!
    
    
    asm.write_to jit_buffer
    
    
    jit_buffer.executable!
    
    
    # Execute the JIT buffer
    
    
    p jit_buffer.to_function([], -Fiddle::TYPE_INT).call.to_s(16) #
    => f00dcafe
    JIT Code
    

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52. AArch64 Example
    JIT a function that returns 0xF00DCAFE
    $ gel exec ruby test.rb
    
    
    "f00dcafe"
    Terminal Output
    require "aarch64"
    
    
    require "jit_buffer"
    
    
    # create a JIT buffer
    
    
    jit_buffer = JITBuffer.new 4096
    
    
    asm = AArch64::Assembler.new
    
    
    # Make some instructions
    
    
    asm.pretty do
    
    
    asm.movz x0, 0xCAFE
    
    
    asm.movk x0, 0xF00D, lsl(16)
    
    
    asm.ret
    
    
    end
    
    
    # Write the instructions to a JIT buffer
    
    
    jit_buffer.writeable!
    
    
    asm.write_to jit_buffer
    
    
    jit_buffer.executable!
    
    
    # Execute the JIT buffer
    
    
    p jit_buffer.to_function([], -Fiddle::TYPE_INT).call.to_s(16) #
    => f00dcafe
    JIT Code
    JITBuffer.new
    

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53. JITBuffer:
    
    
    Executable Memory
    

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54. Linux / macOS
    

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55. Any Platform
    

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56. Test Code Execution
    Write some bytes and ensure it can execute them
    # create a JIT buffer
    
    
    jit_buffer = JITBuffer.new 4096
    
    
    # Write the instructions to a JIT buffer
    
    
    jit_buffer.writeable!
    
    
    jit_buffer.write asm.to_binary
    
    
    jit_buffer.executable!
    
    
    # Execute the JIT buffer
    
    
    p jit_buffer.to_function([],
    
    
    -Fiddle::TYPE_INT).call
    

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57. Test on x86_64 and ARM
    

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58. Test Code Execution
    Add a check for the current platform
    # create a JIT buffer
    
    
    jit_buffer = JITBuffer.new 4096
    
    
    # Write the instructions to a JIT buffer
    
    
    jit_buffer.writeable!
    
    
    if arm64?
    
    
    jit_buffer.write arm64_bytes
    
    
    else
    
    
    jit_buffer.write x86_bytes
    
    
    end
    
    
    jit_buffer.executable!
    

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59. Test Code Execution
    Add a check for the current platform
    # create a JIT buffer
    
    
    jit_buffer = JITBuffer.new 4096
    
    
    # Write the instructions to a JIT buffer
    
    
    jit_buffer.writeable!
    
    
    if arm64?
    
    
    jit_buffer.write arm64_bytes
    
    
    else
    
    
    jit_buffer.write x86_bytes
    
    
    end
    
    
    jit_buffer.executable!
    

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60. If Statements Mean "Complexity"
    

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61. Not "Cool"
    

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62. Can we ask the CPU itself?
    

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63. Machine Code is Just Bytes
    

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64. Bytes Valid for
    
    
    x86_64 and ARM64?
    

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65. YES!
    

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66. Worst Best Idea Ever!
    

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67. x86 Machine Code
    Very Cool Code (Intel Syntax)
    .foo:
    
    
    mov rax, 0x2b
    
    
    ret
    
    
    jmp foo
    Put 0x2b in the
    "RAX" register
    Return from the
    current function
    Jump to the "foo"
    label???
    

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68. x86 Machine Code Bytes
    Bytes are in base 16
    48 C7 C0 2B 00 00 00 mov rax, 0x2b
    C3 ret
    EB F6 jmp foo
    [0x48, 0xc7, 0xc0, 0x2b, 0x00, 0x00, 0x00, 0xc3, 0xeb, 0xf6]
    
    
    

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69. ARM64 Machine Code
    Very Very Cool Code
    movz X11, 0x7b7
    
    
    movz X0, 0x2b
    
    
    ret
    Write 0x7b7 to
    X11 register
    because???
    Write 0x2b to the
    X0 register
    Return from the
    current function
    

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70. ARM64 Machine Code Bytes
    Bytes are in base 16
    EB F6 80 D2 movz x11, 0x7b7
    60 05 80 D2 movz x0, 0x2b
    C0 03 5F D6 ret
    

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71. Machine Code for x86 and ARM64
    x86_64 Machine Code
    48 C7 C0 2B 00 00 00 mov rax, 0x2b
    C3 ret
    EB F6 jmp foo
    ARM64 Machine Code
    EB F6 80 D2 movz x11, 0x7b7
    60 05 80 D2 movz x0, 0x2b
    C0 03 5F D6 ret
    

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72. Machine Code for x86 and ARM64
    x86_64 Machine Code
    48 C7 C0 2B 00 00 00 mov rax, 0x2b
    C3 ret
    EB F6 jmp foo
    ARM64 Machine Code
    EB F6 80 D2 movz x11, 0x7b7
    60 05 80 D2 movz x0, 0x2b
    C0 03 5F D6 ret
    

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73. Machine Code for x86 and ARM64
    48 C7 C0 2B 00 00 00 mov rax, 0x2b
    C3 ret
    EB F6 jmp foo
    EB F6 80 D2 movz x11, 0x7b7
    60 05 80 D2 movz x0, 0x2b
    C0 03 5F D6 ret
    

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74. Machine Code for x86 and ARM64
    48 C7 C0 2B 00 00 00 mov rax, 0x2b
    C3 ret
    EB F6 jmp foo
    EB F6 80 D2
    60 05 80 D2 movz x0, 0x2b
    C0 03 5F D6 ret
    

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75. Machine Code for x86 and ARM64
    48 C7 C0 2B 00 00 00 mov rax, 0x2b
    C3 ret
    EB F6
    EB F6 80 D2 movz x11, 0x7b7
    60 05 80 D2 movz x0, 0x2b
    C0 03 5F D6 ret
    

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76. Both Return 0x2B
    

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77. JITBuffer Test Case
    VCP (Very Cool Program)
    jit = JITBuffer.new 4096
    
    
    bytes = [0x48, 0xc7, 0xc0, 0x2b, 0x00, 0x00, 0x00, # x86_64 mov rax, 0x2b
    
    
    0xc3, # x86_64 ret
    
    
    0xeb, 0xf6, # x86 jmp
    
    
    0x80, 0xd2, # ARM movz X11, 0x7b7
    
    
    0x60, 0x05, 0x80, 0xd2, # ARM movz X0, #0x2b
    
    
    0xc0, 0x03, 0x5f, 0xd6] # ARM ret
    
    
    jit.writeable!
    
    
    jit.write bytes.pack("C*")
    
    
    jit.executable!
    
    
    func = Fiddle::Function.new(jit.to_i + 8, [], Fiddle::TYPE_INT)
    
    
    assert_equal 0x2b, func.call
    Start at
    offset 8
    Offset 8
    Alw
    ays
    0x2b!!
    

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78. Cross Platform!!!!!*
    *x86_64 and ARM64 only
    

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79. No If Statements!
    

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80. Complexity: 0
    

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81. So Simple!
    

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82. "Just because you can, doesn't
    mean you should!"
    

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84. Anatomy of a Tenderlove Talk
    

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85. Tenderlove Talk Timeline Teardown
    Jokes about local
    businesses
    Pictures of Cats
    W
    eird
    code
    not
    related
    to
    the
    topic
    M
    ain
    topic
    Abrupt ending
    after
    running
    out of tim
    e
    

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86. Talk Timeline Breakdown
    Jokes about local
    businesses
    Pictures of Cats
    W
    eird
    code
    not
    related
    to
    the
    topic
    M
    ain
    topic
    Abrupt ending
    after
    running
    out of tim
    e
    

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87. New Features in Rails 7!!
    Rack
    

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88. Spring
    It is gone!
    

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90. New Features in Rails 7
    Cool!
    • Import maps
    
    
    • Hotwire Default
    
    
    • Turbo 7 Default
    
    
    • Stimulus 3 Default
    
    
    • JS Bundling
    
    
    • CSS Bundling
    

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92. I am not a
    Front End Developer
    

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93. No Idea
    what these words mean
    

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94. But It's OK
    

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95. Import Maps and ES Modules
    

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96. Sprockets
    Webpacker
    ESM + Import Maps
    

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97. 🫠🫠🫠🫠
    "yay"
    

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98. New application.html.erb
    javascript_importmap_tags
    
    
    
    
    
    
    
    
    
    Myapp
    
    
    
    
    
    <%= csrf_meta_tags %>
    
    
    <%= csp_meta_tag %>
    
    
    <%= stylesheet_link_tag "application", "data-turbo-track": "reload" %>
    
    
    <%= javascript_importmap_tags %>
    
    
    
    
    
    
    
    
    <%= yield %>
    
    
    
    
    
    
    

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99. Define importmaps
    con
    fi
    g/importmap.rb
    # Pin npm packages by running ./bin/importmap
    
    
    pin "application", preload: true
    
    
    pin "@hotwired/turbo-rails", to: "turbo.min.js", preload: true
    
    
    pin "@hotwired/stimulus", to: "stimulus.min.js", preload: true
    
    
    pin "@hotwired/stimulus-loading", to: "stimulus-loading.js", preload: true
    
    
    pin_all_from "app/javascript/controllers", under: "controllers"
    

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100. Rendered Application Layout
     Import map automatically generated
     {<br/><br/><br/>"imports": {<br/><br/><br/>"application": "/assets/application-123.js",<br/><br/><br/>"@hotwired/turbo-rails": "/assets/turbo.min-123.js",<br/><br/><br/>"@hotwired/stimulus": "/assets/stimulus.min-123.js",<br/><br/><br/>"@hotwired/stimulus-loading": "/assets/stimulus-loading-123.js",<br/><br/><br/>"controllers/application": "/assets/controllers/application-123.js",<br/><br/><br/>"controllers/hello_controller": "/assets/controllers/hello_controller-123.js",<br/><br/><br/>"controllers": "/assets/controllers/index-123.js"<br/><br/><br/>}<br/><br/><br/>}
     

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101. Pinning Libraries
     

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102. Put a pin in it!
     Add stu
     ff
     to the import map
     $ bin/importmap pin lodash-es@4.17.21/startCase.js
     
     
     Pinning "lodash-es/startCase.js" to https://ga.jspm.io/npm:lodash-es@4.17.21/startCase.js
     es: Español
     

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103. New config/importmap.rb
     With lodash-es
     # Pin npm packages by running ./bin/importmap
     
     
     pin "application", preload: true
     
     
     pin "@hotwired/turbo-rails", to: "turbo.min.js", preload: true
     
     
     pin "@hotwired/stimulus", to: "stimulus.min.js", preload: true
     
     
     pin "@hotwired/stimulus-loading", to: "stimulus-loading.js", preload: true
     
     
     pin_all_from "app/javascript/controllers", under: "controllers"
     
     
     pin "lodash-es/startCase.js", to: "https://ga.jspm.io/npm:lodash-es@4.17.21/startCase.js"
     

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104. New config/importmap.rb
     With lodash-es
     # Pin npm packages by running ./bin/importmap
     
     
     pin "application", preload: true
     
     
     pin "@hotwired/turbo-rails", to: "turbo.min.js", preload: true
     
     
     pin "@hotwired/stimulus", to: "stimulus.min.js", preload: true
     
     
     pin "@hotwired/stimulus-loading", to: "stimulus-loading.js", preload: true
     
     
     pin_all_from "app/javascript/controllers", under: "controllers"
     
     
     pin "lodash-es/startCase.js", to: "https://ga.jspm.io/npm:lodash-es@4.17.21/startCase.js"
     

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105. New config/importmap.rb
     With lodash-es
     # Pin npm packages by running ./bin/importmap
     
     
     pin "application", preload: true
     
     
     pin "@hotwired/turbo-rails", to: "turbo.min.js", preload: true
     
     
     pin "@hotwired/stimulus", to: "stimulus.min.js", preload: true
     
     
     pin "@hotwired/stimulus-loading", to: "stimulus-loading.js", preload: true
     
     
     pin_all_from "app/javascript/controllers", under: "controllers"
     
     
     pin "@lodash/startCase", to: "https://ga.jspm.io/npm:lodash-es@4.17.21/startCase.js"
     

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106. New Sourcemap
     Has Lowdash!
     {<br/><br/><br/>"imports": {<br/><br/><br/>"application": "/assets/application-123.js",<br/><br/><br/>"@hotwired/turbo-rails": "/assets/turbo.min-123.js",<br/><br/><br/>"@hotwired/stimulus": "/assets/stimulus.min-123.js",<br/><br/><br/>"@hotwired/stimulus-loading": "/assets/stimulus-loading-123.js",<br/><br/><br/>"@lodash/startCase": "https://ga.jspm.io/npm:lodash-es@4.17.21/startCase.js",<br/><br/><br/>"controllers/application": "/assets/controllers/application-123.js",<br/><br/><br/>"controllers/hello_controller": "/assets/controllers/hello_controller-123.js",<br/><br/><br/>"controllers": "/assets/controllers/index-123.js"<br/><br/><br/>}<br/><br/><br/>}
     

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107. New Sourcemap
     Has Lowdash!
     {<br/><br/><br/>"imports": {<br/><br/><br/>"application": "/assets/application-123.js",<br/><br/><br/>"@hotwired/turbo-rails": "/assets/turbo.min-123.js",<br/><br/><br/>"@hotwired/stimulus": "/assets/stimulus.min-123.js",<br/><br/><br/>"@hotwired/stimulus-loading": "/assets/stimulus-loading-123.js",<br/><br/><br/>"@lodash/startCase": "https://ga.jspm.io/npm:lodash-es@4.17.21/startCase.js",<br/><br/><br/>"controllers/application": "/assets/controllers/application-123.js",<br/><br/><br/>"controllers/hello_controller": "/assets/controllers/hello_controller-123.js",<br/><br/><br/>"controllers": "/assets/controllers/index-123.js"<br/><br/><br/>}<br/><br/><br/>}
     

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108. Use the new module!
     <br/><br/><br/>import startCase from '@lodash/startCase';<br/><br/><br/>const el = document.createElement('h1');<br/><br/><br/>const words = "hello, mom!"<br/><br/><br/>const text = document.createTextNode(startCase(words));<br/><br/><br/>el.appendChild(text);<br/><br/><br/><br/><br/>document.body.appendChild(el);<br/><br/><br/>
     

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110. Great!
     

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111. Indirect Names
     Use names rather than
     fi
     les
     {<br/><br/><br/>"imports": {<br/><br/><br/>"application": "/assets/application-123.js",<br/><br/><br/>"@hotwired/turbo-rails": "/assets/turbo.min-123.js",<br/><br/><br/>"@hotwired/stimulus": "/assets/stimulus.min-123.js",<br/><br/><br/>"@hotwired/stimulus-loading": "/assets/stimulus-loading-123.js",<br/><br/><br/>"controllers/application": "/assets/controllers/application-123.js",<br/><br/><br/>"controllers/hello_controller": "/assets/controllers/hello_controller-123.js",<br/><br/><br/>"controllers": "/assets/controllers/index-123.js"<br/><br/><br/>}<br/><br/><br/>}
     
     
     

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112. Indirect Names
     Use names rather than
     fi
     les
     {<br/><br/><br/>"imports": {<br/><br/><br/>"application": "/assets/application-123.js",<br/><br/><br/>"@hotwired/turbo-rails": "/assets/turbo.min-123.js",<br/><br/><br/>"@hotwired/stimulus": "/assets/stimulus.min-123.js",<br/><br/><br/>"@hotwired/stimulus-loading": "/assets/stimulus-loading-123.js",<br/><br/><br/>"controllers/application": "/assets/controllers/application-123.js",<br/><br/><br/>"controllers/hello_controller": "/assets/controllers/hello_controller-123.js",<br/><br/><br/>"controllers": "/assets/controllers/index-123.js"<br/><br/><br/>}<br/><br/><br/>}
     
     
     

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113. We're Not Bundling JS
     

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114. Better Caching
     

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115. More Requests
     

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116. HTTP2: Concurrent Requests on
     a Single Socket
     

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117. Rack
     

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118. Rack Defines an Interface
     Easily change webservers
     Rack Application
     Webserver
     Falcon
     

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119. Rack Interface
     rack_app = lambda do |env|
     
     
     [200, {}, ["neat"]]
     
     
     end
     
     
     def webserver(app)
     
     
     status, headers, body = app.call({})
     
     
     $socket.puts status
     
     
     $socket.puts headers
     
     
     body.each do |chunk|
     
     
     $socket.puts chunk
     
     
     end
     
     
     end
     
     
     webserver(rack_app)
     Rack App
     Webserver
     Request
     
     
     Data
     Response
     
     
     Data
     

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120. Rack + HTTP
     

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121. Rack + TCP Connection
     

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122. HTTP Timeline + First Commit of Rack
     Starting with HTTP/0.9
     1990
     1998
     2006
     2014
     2022
     Websockets
     2011
     HTTP/3
     2020
     HTTP/2
     2015
     Rack
     2007
     HTTP/1.1
     1997
     HTTP/1.0
     1996
     HTTP/0.9
     1991
     

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123. HTTP 0.9 Request / Response
     Connections were closed
     Client New TCP Connection Server
     HTTP Request
     HTTP Response
     perl ...
     ENV
     rack_app = lambda do |env|
     
     
     [200, {}, ["neat"]]
     
     
     end
     

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124. HTTP/1.0
     RFC 1945
     1990
     1998
     2006
     2014
     2022
     Websockets
     2011
     HTTP/3
     2020
     HTTP/2
     2015
     Rack
     2007
     HTTP/1.1
     1997
     HTTP/1.0
     1996
     HTTP/0.9
     1991
     

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125. Connections are Expensive
     

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126. Serial Requests
     

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127. Fetch assets in parallel?
     
     
     
     
     
     
     
     
     
     
     
     
     HELLO!
     
     
     Happy Friday!!!
     
     
     
     
     
     
     

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128. HTTP/1.1
     RFC 2068
     1990
     1998
     2006
     2014
     2022
     Websockets
     2011
     HTTP/3
     2020
     HTTP/2
     2015
     Rack
     2007
     HTTP/1.1
     1997
     HTTP/1.0
     1996
     HTTP/0.9
     1991
     

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129. HTTP/1.1: Keep Alive
     

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130. HTTP 1.1 Request / Response
     Connections are kept open
     Client New TCP Connection Server
     HTTP Request
     HTTP Response
     ruby ...
     ruby ...
     HTTP Request
     HTTP Response
     

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131. HTTP/1.1: Have 2 Connections
     

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132. HTTP 1.1 Multiple Connections
     Thanks buddy!
     New TCP Connection Server
     HTTP Request
     HTTP Response
     ruby ...
     ruby ...
     HTTP Request
     HTTP Response
     Client
     New TCP Connection Server
     HTTP Request
     HTTP Response
     ruby ...
     ruby ...
     HTTP Request
     HTTP Response
     

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133. Requests Are Still Serial
     

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134. Bundling Assets
     

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135. Rack is released!
     Version 0.1
     1990
     1998
     2006
     2014
     2022
     Websockets
     2011
     HTTP/3
     2020
     HTTP/2
     2015
     Rack
     2007
     HTTP/1.1
     1997
     HTTP/1.0
     1996
     HTTP/0.9
     1991
     

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136. Based on PEP 333
     

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137. "HTTP Translation"
     

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138. Environment Variables -> Hash
     

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139. stdout -> [200, {}, ["hi"]]
     

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140. Full Rack Application Example
     rack_app = lambda do |env|
     
     
     [200, # Status Code
     
     
     { "X-Cool-Header" => "Neat" }, # Headers
     
     
     ["Response Body"]] # Response Body
     
     
     end
     

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141. Websockets
     Sockets, but for the web!
     1990
     1998
     2006
     2014
     2022
     Websockets
     2011
     HTTP/3
     2020
     HTTP/2
     2015
     Rack
     2007
     HTTP/1.1
     1997
     HTTP/1.0
     1996
     HTTP/0.9
     1991
     

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142. Bidirectional Communication
     

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143. Websockets: NOT HTTP
     

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144. 2013: Rack 1.5
     

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145. Hijacking: Slap a proc in there!
     Get access to the socket
     rack_app = lambda do |env|
     
     
     io = env["rack.hijack"].call
     
     
     io.write "neat"
     
     
     io.close # socket is closed
     
     
     # Return stuff?
     
     
     [200, {}, []]
     
     
     end
     

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146. HTTP Translator +
     
     
     Socket Getter? 🤷
     

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147. HTTP/2
     It's 0.9 better than HTTP 1.1
     1990
     1998
     2006
     2014
     2022
     Websockets
     2011
     HTTP/3
     2020
     HTTP/2
     2015
     Rack
     2007
     HTTP/1.1
     1997
     HTTP/1.0
     1996
     HTTP/0.9
     1991
     

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148. SSL Encouraged
     

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149. Compressed Headers
     

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150. Binary Protocol
     

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151. Request / Response Multiplexing
     Concurrent requests on the same socket
     Client New SSL TCP Connection Server
     H2 Request 1
     H2 Response 2
     ruby ...
     ruby ...
     H2 Request 2
     H2 Response 1
     

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152. Import Maps
     

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153. Rails 7:
     
     
     We want you to use H2?
     

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154. How?
     

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155. https://github.com/socketry/falcon
     

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156. HTTP2 Proxy Server
     

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157. HTTP 2 Proxy Server
     Proxy translates to HTTP 1.1
     H2O Unicorn Rails
     HTTP 1.1 Rack
     HTTP 2
     

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158. Push Promise
     

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159. "Take this resource"
     

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160. What if the client already has the
     resource cached? 😅
     

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161. Push Promise in HTTP 1.1
     

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162. HTTP Status Code 103:
     
     
     Early Hints
     

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163. Sending Server Push with H2 Proxy
     HTTP 1.1 server sends 103, proxy converts to PUSH
     HTTP/1.1 103 Early Hints
     
     
     Link: ; rel=preload; as=style
     
     
     Link: ; rel=preload; as=script
     
     
     HTTP/1.1 200 OK
     
     
     Date: Fri, 26 May 2022 10:02:11 GMT
     
     
     Content-Length: 1234
     
     
     Content-Type: text/html; charset=utf-8
     
     
     Link: ; rel=preload; as=style
     
     
     Link: ; rel=preload; as=script
     HTTP 1.1 Response
     

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164. Sending Server Push with H2 Proxy
     HTTP 1.1 server sends 103, proxy converts to PUSH
     HTTP/1.1 103 Early Hints
     
     
     Link: ; rel=preload; as=style
     
     
     Link: ; rel=preload; as=script
     HTTP 103 Response
     H2O Unicorn
     HTTP 1.1
     HTTP 2
     PUSH /style.css
     PUSH /script.js
     

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165. Rails + (Puma || Falcon)
     

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166. Slap another lambda in the env hash!
     Great!
     class Server
     
     
     def call env
     
     
     env['rack.early_hints'].call([
     
     
     { link: "/style.css", as: "style" }, # push /style.css
     
     
     { link: "/script.js" }]) # push /script.js
     
     
     [200, { "X-Hello" => "World" }, ["Hello world!"]]
     
     
     end
     
     
     end
     

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167. 2020: HTTP/3
     

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168. Rails 7 is HTTP/2 by default
     

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169. Do we need H2 servers?
     

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170. What does H2 mean for Hijack?
     

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171. Slapping lambdas in a hash
     seems unsustainable
     

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172. Next Generation Rack
     

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173. Easy to Use
     

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174. Easy to Extend
     

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175. Easy to Deploy
     

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176. This Whole Thing Is Moot
     

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177. Ruby 3.1: WASM support
     

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178. https://ruby-syntax-tree.github.io
     

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179. Next Year:
     
     
     Rails in the browser,
     
     
     React on the server
     

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180. THANKS
     PORTLAND!
     See you next year! 😘
     

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