RailsConf 2023

Transcript

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2. It's the Final Keynote!
   

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3. Increase Creativity!
   

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4. Modern Dev Environments
   Programmer Efficiency in 2023?
   

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5. Artificial Intelligence
   

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6. ChatGPT
   

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7. GitHub Copilot
   

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8. Editors
   

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9. VSCode
   

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10. Language Servers
    

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12. Technical
    Content
    

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13. Hi, I'm Aaron!
    

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14. @tenderlove
    @[email protected]
    

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17. —Eileen Uchitelle
    “I remain on the Rails core team for you.
    To make Rails better for the community”
    

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18. —Aaron
    “Notice me Senpai!’
    

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19. RAILS CONF!!!!
    

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20. Bona Fide Mycologist
    

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26. I don’t value my time
    

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27. Other Hobbies
    

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30. I love programming
    

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31. http://youtube.com/
    tenderlovescoolstuff
    

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32. http://youtube.com/
    tenderlovescoolstuff
    CLICK HERE!!
    

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33. Rails monkey
    patched
    that??
    

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34. That’s not
    your active job!
    

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35. I’m not saying it was Active
    Support, but it definitely was.
    

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36. I am old 㻝
    

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37. I am old 㻝
    

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39. The best time to be a programmer
    is now.
    

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40. Syntax Highlighting 㷠
    

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41. Garbage Collection
    

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43. Convention over
    Configuration
    

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44. Making Decisions For Us
    

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45. Example Spring Java Bean
    This is how we programmed in the early 2000's
    
    
    
    
    
    
    
    
    
    
    
    

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46. Meetings about column names
    

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47. Design documents about DAOs
    

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48. Data Access Object
    

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49. Rails: Follow the Convention and
    everything Just Works
    

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50. Less Code
    Fewer Decisions
    Fewer Distractions
    

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51. 㻑
    

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52. Thinking Sucks!
    

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53. Think about your app,
    not primary key names
    

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54. THEY DID What??
    

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55. Artificial Intelligence
    Chatgpt
    GitHub
    Copilot
    BARD
    Bing
    chat
    

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56. Fake Intelligence,
    Real Problems
    

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57. Licensing Issues?
    

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58. Ethics?
    

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59. Believable Bullshit
    

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60. Could be true?
    

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61. Someone, Probably
    “AI users are only wasting their own time”
    

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63. View Slide

64. -- VPP (Very Patient Person)
    Hi, large language models like ChatGPT don't actually “know"
    exactly how to use command line tools like GitHub CLI, so they
    make up command invocations that sound plausible but may or
    may not exist.
    

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66. Drudgery
    

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69. — Me, in the future
    “Copilot, please fix these tests”
    

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71. Red, Green, Refactor
    Adding the Feature / Tests
    Fixing the Tests
    Refactor the Code
    

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73. Spend Less Time on
    “Boring” Tasks
    

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75. Editors
    

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77. Awkward!
    

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78. Language Server
    

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79. Language Server Protocol
    (LSP)
    

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80. Language Server is a Program
    

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81. clangd
    Language Server Protocol
    

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82. clangd
    Language Server Protocol
    

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83. Language
    Server
    Protocol
    

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84. Rack
    

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85. Technical Content
    

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86. Developing a
    Language Server
    

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88. VSCode Extension
    

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90. Configuring Vim
    Add clangd support
    # Tell Vim to find vim-lsp
    packadd vim-lsp
    # Use clangd if available
    if executable('clangd')
    au User lsp_setup call lsp#register_server({
    \ 'name': 'clangd',
    \ 'cmd': ['clangd'],
    \ 'allowlist': ['c'],
    \ })
    endif
    Use the “clangd”
    command
    Only enable it on C
    files
    

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91. Check Syntax
    But only check syntax on Save
    def foo
    if
    end
    

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92. Communicate via
    STDIN / STDOUT or TCP
    

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93. Typical Order of Operations
    Open foo.rb
    Ruby LSP
    Open bar.rb
    

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94. Language Server Protocol
    Just JSON with a header
    Content-Length: 1234\r\n
    Content-Type: application/vscode-jsonrpc; charset=utf-8\r\n
    \r\n
    { cool:"stuff",live:"stream"...}
    Content-Type
    is optional!
    

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95. Not Request / Response
    

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96. Events, encoded as JSON
    

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97. Respond to events with `id`
    

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98. Event Message Reader
    Read Messages from $stdin and Parse
    module LSP
    class Reader
    def initialize
    @io = $stdin.binmode
    end
    def read
    buffer = @io.gets("\r\n\r\n")
    content_length = buffer.match(/Content-Length: (\d+)/i)[1].to_i
    message = @io.read(content_length)
    JSON.parse message, symbolize_names: true
    end
    end
    end
    Read Header in
    to a Buffer Get Content
    Length
    Read JSON event
    and parse
    

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99. Event Message Writer
    Write Hash as JSON to $stdout
    module LSP
    class Writer
    def initialize
    @io = $stdout.binmode
    end
    def write response
    str = JSON.dump(response.merge("jsonrpc" => "2.0"))
    @io.write "Content-Length: #{str.bytesize}\r\n"
    @io.write "\r\n"
    @io.write str
    @io.flush
    end
    end
    end
    Add Required Key
    Calculate and
    write length
    Send JSON Body
    

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100. Event Loop
     module LSP
     def self.run
     reader = Reader.new
     writer = Writer.new
     # Handle events
     subscriber = LSP::Events.new
     loop do
     # Read an event
     message = reader.read
     # Ask the handler to handle the event
     subscriber.handle message[:method], message, writer
     end
     end
     end
     

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101. First Event
     “initialize” event
     Content-Length: 2683\r\n
     \r\n
     {"id":1,"jsonrpc":"2.0","method":"initialize","params":{"rootUri":"file:///Users/aaron/git/lsp-stream","capabilities":{"workspace":
     {"workspaceFolders":false,"configuration":true,"symbol":{"dynamicRegistration":false},"applyEdit":true},"window":
     {"workDoneProgress":false},"textDocument":{"callHierarchy":{"dynamicRegistration":false},"rename":
     {"prepareSupport":true,"dynamicRegistration":false,"prepareSupportDefaultBehavior":1},"codeAction":
     {"isPreferredSupport":true,"disabledSupport":true,"codeActionLiteralSupport":{"codeActionKind":{"valueSet":
     ["","quickfix","refactor","refactor.extract","refactor.inline","refactor.rewrite","source","source.organizeImports"]}},"dynamicRegistration":false
     },"completion":{"completionItem":{"snippetSupport":false,"resolveSupport":{"properties":["additionalTextEdits"]},"documentationFormat":
     ["markdown","plaintext"]},"dynamicRegistration":false,"completionItemKind":{"valueSet":
     [10,11,12,13,14,15,16,17,18,19,20,21,22,23,24,25,1,2,3,4,5,6,7,8,9]}},"formatting":{"dynamicRegistration":false},"codeLens":
     {"dynamicRegistration":false},"inlayHint":{"dynamicRegistration":false},"hover":{"dynamicRegistration":false,"contentFormat":
     ["markdown","plaintext"]},"rangeFormatting":{"dynamicRegistration":false},"declaration":
     {"dynamicRegistration":false,"linkSupport":true},"references":{"dynamicRegistration":false},"typeHierarchy":
     {"dynamicRegistration":false},"foldingRange":{"rangeLimit":5000,"dynamicRegistration":false,"lineFoldingOnly":true},"documentSymbol":
     {"symbolKind":{"valueSet":
     [10,11,12,13,14,15,16,17,18,19,20,21,22,23,24,25,26,1,2,3,4,5,6,7,8,9]},"dynamicRegistration":false,"labelSupport":false,"hierarchicalDocumentSymb
     olSupport":false},"publishDiagnostics":{"relatedInformation":true},"synchronization":
     {"dynamicRegistration":false,"willSaveWaitUntil":false,"willSave":false,"didSave":true},"documentHighlight":
     {"dynamicRegistration":false},"implementation":{"dynamicRegistration":false,"linkSupport":true},"typeDefinition":
     {"dynamicRegistration":false,"linkSupport":true},"semanticTokens":{"serverCancelSupport":false,"requests":
     {"full":false,"range":false},"multilineTokenSupport":false,"dynamicRegistration":false,"overlappingTokenSupport":false,"tokenTypes":
     ["type","class","enum","interface","struct","typeParameter","parameter","variable","property","enumMember","event","function","method","macro","ke
     yword","modifier","comment","string","number","regexp","operator"],"tokenModifiers":[],"formats":["relative"]},"signatureHelp":
     {"dynamicRegistration":false},"definition":{"dynamicRegistration":false,"linkSupport":true}}},"rootPath":"/Users/aaron/git/lsp-
     stream","clientInfo":{"name":"vim-lsp"},"processId":51035,"trace":"off"}}
     

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102. First Event
     “initialize” event
     Content-Length: 2683\r\n
     \r\n
     {"id":1,"jsonrpc":"2.0","method":"initialize","params":{"rootUri":"file:///Users/aaron/git/lsp-stream","capabilities":{"workspace":
     {"workspaceFolders":false,"configuration":true,"symbol":{"dynamicRegistration":false},"applyEdit":true},"window":
     {"workDoneProgress":false},"textDocument":{"callHierarchy":{"dynamicRegistration":false},"rename":
     {"prepareSupport":true,"dynamicRegistration":false,"prepareSupportDefaultBehavior":1},"codeAction":
     {"isPreferredSupport":true,"disabledSupport":true,"codeActionLiteralSupport":{"codeActionKind":{"valueSet":
     ["","quickfix","refactor","refactor.extract","refactor.inline","refactor.rewrite","source","source.organizeImports"]}},"dynamicRegistration":false
     },"completion":{"completionItem":{"snippetSupport":false,"resolveSupport":{"properties":["additionalTextEdits"]},"documentationFormat":
     ["markdown","plaintext"]},"dynamicRegistration":false,"completionItemKind":{"valueSet":
     [10,11,12,13,14,15,16,17,18,19,20,21,22,23,24,25,1,2,3,4,5,6,7,8,9]}},"formatting":{"dynamicRegistration":false},"codeLens":
     {"dynamicRegistration":false},"inlayHint":{"dynamicRegistration":false},"hover":{"dynamicRegistration":false,"contentFormat":
     ["markdown","plaintext"]},"rangeFormatting":{"dynamicRegistration":false},"declaration":
     {"dynamicRegistration":false,"linkSupport":true},"references":{"dynamicRegistration":false},"typeHierarchy":
     {"dynamicRegistration":false},"foldingRange":{"rangeLimit":5000,"dynamicRegistration":false,"lineFoldingOnly":true},"documentSymbol":
     {"symbolKind":{"valueSet":
     [10,11,12,13,14,15,16,17,18,19,20,21,22,23,24,25,26,1,2,3,4,5,6,7,8,9]},"dynamicRegistration":false,"labelSupport":false,"hierarchicalDocumentSymb
     olSupport":false},"publishDiagnostics":{"relatedInformation":true},"synchronization":
     {"dynamicRegistration":false,"willSaveWaitUntil":false,"willSave":false,"didSave":true},"documentHighlight":
     {"dynamicRegistration":false},"implementation":{"dynamicRegistration":false,"linkSupport":true},"typeDefinition":
     {"dynamicRegistration":false,"linkSupport":true},"semanticTokens":{"serverCancelSupport":false,"requests":
     {"full":false,"range":false},"multilineTokenSupport":false,"dynamicRegistration":false,"overlappingTokenSupport":false,"tokenTypes":
     ["type","class","enum","interface","struct","typeParameter","parameter","variable","property","enumMember","event","function","method","macro","ke
     yword","modifier","comment","string","number","regexp","operator"],"tokenModifiers":[],"formats":["relative"]},"signatureHelp":
     {"dynamicRegistration":false},"definition":{"dynamicRegistration":false,"linkSupport":true}}},"rootPath":"/Users/aaron/git/lsp-
     stream","clientInfo":{"name":"vim-lsp"},"processId":51035,"trace":"off"}}
     

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103. Event Handling
     Dispatch to methods based on event names
     module LSP
     class Events
     DISPATCH = {
     "initialize" => :on_initialize,
     "textDocument/didSave" => :did_save
     }
     def handle method, message, writer
     send(DISPATCH.fetch(method) { :unknown }, message, writer)
     end
     def on_initialize message, writer
     # ...
     end
     end
     end
     Map event names
     to methods
     Look up methods
     and call them
     

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104. Initialize Message
     Tells the editor what features your server supports (server § editor)
     module LSP
     class Events
     def on_initialize message, writer
     result = {
     "capabilities" => {
     "textDocumentSync" => {
     "openClose" => true, "change" => 1,"save" => true
     }
     }
     }
     writer.write(id: message[:id], result: result)
     end
     end
     end
     Open / Close
     Change
     Save
     

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105. Document Was Saved
     Editor § Server
     {"method":"textDocument/didSave","params":{
     "textDocument":{
     "uri":"file:///Users/aaron/git/minitest/test.rb"}}}
     

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106. Document Was Saved
     Editor § Server
     {"method":"textDocument/didSave","params":{
     "textDocument":{
     "uri":"file:///Users/aaron/git/minitest/test.rb"}}}
     

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107. Document Was Saved
     Editor § Server
     {"method":"textDocument/didSave","params":{
     "textDocument":{
     "uri":"file:///Users/aaron/git/minitest/test.rb"}}}
     

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108. Save Events
     Parse the File, Report Document Diagnostics
     module LSP
     class Events
     def did_save message, writer
     doc = message.dig(:params, :textDocument)
     file = doc[:uri].delete_prefix("file://")
     result = { :uri => doc[:uri], :diagnostics => [ ] }
     error = check_syntax file
     if error
     line_number = error.message[/(?<=:)\d+/].to_i
     line = File.readlines(file)[line_number - 1]
     result = {
     :uri => doc[:uri], :diagnostics => [ {
     "range" => {
     "start" => { "character" => 0, "line" => line_number - 1 },
     "end" => { "character" => line.bytesize, "line" => line_number - 1 },
     },
     "message" => error.message.lines.first,
     "severity" => 1
     }, ], }
     end
     writer.write(method: "textDocument/publishDiagnostics", params: result)
     end
     end
     end
     Set our default
     response
     Check Syntax
     Extract the Line
     Information
     Construct Error
     Report
     Send Error
     Report
     

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109. Checking Syntax
     Try compiling the file
     def check_syntax file
     RubyVM::InstructionSequence.compile_file(file)
     nil
     rescue SyntaxError => e
     e # only return syntax errors
     rescue Exception
     nil # ignore anything else
     end
     

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110. That’s It!
     

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111. Entire Language Server
     It fits on one slide!
     #!/Users/aaron/.rubies/arm64/ruby-trunk/bin/ruby
     require "json"
     module LSP
     class Writer
     def initialize
     @io = $stdout.binmode
     end
     def write response
     str = JSON.dump(response.merge("jsonrpc" => "2.0"))
     @io.write "Content-Length: #{str.bytesize}\r\n"
     @io.write "\r\n"
     @io.write str
     @io.flush
     end
     end
     class Reader
     def initialize
     @io = $stdin.binmode
     end
     def read
     buffer = @io.gets("\r\n\r\n")
     content_length = buffer.match(/Content-Length: (\d+)/i)[1].to_i
     message = @io.read(content_length)
     JSON.parse message, symbolize_names: true
     end
     end
     class Events
     DISPATCH = {
     "initialize" => :on_initialize,
     "textDocument/didSave" => :did_save
     }
     def handle method, message, writer
     send DISPATCH.fetch(method) { :unknown }, message, writer
     end
     def on_initialize message, writer
     result = {
     "capabilities" => {
     "textDocumentSync" => { "openClose" => true, "change" => 1,"save" => true }
     }
     }
     writer.write(id: message[:id], result: result)
     end
     

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112. View Slide

113. Implement Other Events
     

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114. Implement other Checks
     

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115. Language Server Protocol
     https://microsoft.github.io/language-server-protocol/
     

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116. https://gist.github.com/tenderlove/
     9a18be7a27ba7a074a8ba8fbf554e794
     

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118. Application Record
     So Many Generated Methods!
     class User < ApplicationRecord
     end
     

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119. Routes Files
     Even More Generated Methods!
     Rails.application.routes.draw do
     resources :users
     resources :posts
     end
     

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120. Tapioca
     https://github.com/Shopify/tapioca
     

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121. — Me, in my head, but now out loud at RailsConf
     “What if Rails had a built-in Language
     Server?”
     

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122. Prototype: Refreshing
     https://github.com/tenderlove/refreshing
     

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123. Hover Info for Active Record
     

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125. Jump to “Definition”
     

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127. Hover Info for URL Helpers
     

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129. NICE!
     

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130. Jump to Definition for URL
     Helpers
     㷉
     

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131. View Slide

132. Automatic Refreshing and
     Error Highlighting
     

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133. View Slide

134. We’re all TDD’ing our views
     though, right?
     

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135. More Ideas!
     

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136. Ruby LSP Rails
     https://github.com/Shopify/ruby-lsp-rails
     

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137. Language Server Hacks
     

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138. App Must Be Running
     

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139. Fetching Active Record Columns
     Check that the constant inherits from Active Record
     if token && token =~ /^[A-Z]/
     begin
     const = Object.const_get(token)
     value = "# #{const.name}\n"
     if const < ActiveRecord::Base
     name_header = "Column Name"
     type_header = "Column Type"
     info = [[name_header, type_header]] + const.columns.map { |column|
     ["`" + column.name.to_s + "`", column.type.to_s]
     }
     max_name_len = info.map(&:first).sort_by(&:length).last.length
     max_type_len = info.map(&:last).sort_by(&:length).last.length
     name_header, type_header = *info.shift
     value << ("| " + name_header.ljust(max_name_len))
     value << (" | " + type_header.ljust(max_type_len) + " |\n")
     value << ("| " + ("-" * max_name_len))
     value << (" | " + ("-" * max_type_len) + " |\n")
     info.each do |name, type|
     value << ("| " + name.ljust(max_name_len))
     value << (" | " + type.ljust(max_type_len) + " |\n")
     end
     end
     rescue NameError
     end
     end
     

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140. Fetching Active Record Columns
     Check that the constant inherits from Active Record
     if token && token =~ /^[A-Z]/
     begin
     const = Object.const_get(token)
     value = "# #{const.name}\n"
     if const < ActiveRecord::Base
     name_header = "Column Name"
     type_header = "Column Type"
     info = [[name_header, type_header]] + const.columns.map { |column|
     ["`" + column.name.to_s + "`", column.type.to_s]
     }
     max_name_len = info.map(&:first).sort_by(&:length).last.length
     max_type_len = info.map(&:last).sort_by(&:length).last.length
     name_header, type_header = *info.shift
     value << ("| " + name_header.ljust(max_name_len))
     value << (" | " + type_header.ljust(max_type_len) + " |\n")
     value << ("| " + ("-" * max_name_len))
     value << (" | " + ("-" * max_type_len) + " |\n")
     info.each do |name, type|
     value << ("| " + name.ljust(max_name_len))
     value << (" | " + type.ljust(max_type_len) + " |\n")
     end
     end
     rescue NameError
     end
     end
     

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141. Fetching Active Record Columns
     Check that the constant inherits from Active Record
     if token && token =~ /^[A-Z]/
     begin
     const = Object.const_get(token)
     value = "# #{const.name}\n"
     if const < ActiveRecord::Base
     name_header = "Column Name"
     type_header = "Column Type"
     info = [[name_header, type_header]] + const.columns.map { |column|
     ["`" + column.name.to_s + "`", column.type.to_s]
     }
     max_name_len = info.map(&:first).sort_by(&:length).last.length
     max_type_len = info.map(&:last).sort_by(&:length).last.length
     name_header, type_header = *info.shift
     value << ("| " + name_header.ljust(max_name_len))
     value << (" | " + type_header.ljust(max_type_len) + " |\n")
     value << ("| " + ("-" * max_name_len))
     value << (" | " + ("-" * max_type_len) + " |\n")
     info.each do |name, type|
     value << ("| " + name.ljust(max_name_len))
     value << (" | " + type.ljust(max_type_len) + " |\n")
     end
     end
     rescue NameError
     end
     end
     

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142. URL Helper Information
     “rake routes” already knows this info!
     value = ''
     if token && token =~ /^([a-z_]+)(_path|_url)$/
     # check if it's a route helper
     if Rails.application.routes.named_routes.key?($1)
     route = Rails.application.routes.named_routes.get($1)
     controller = route.requirements[:controller]
     action = route.requirements[:action]
     value = "* URI Pattern: `#{route.path.spec}`\n* Controller#Action: `#{controller}
     ##{action}`"
     else
     value = "Something else"
     end
     else
     # Other Stuff
     end
     

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143. URL Helper Information
     “rake routes” already knows this info!
     value = ''
     if token && token =~ /^([a-z_]+)(_path|_url)$/
     # check if it's a route helper
     if Rails.application.routes.named_routes.key?($1)
     route = Rails.application.routes.named_routes.get($1)
     controller = route.requirements[:controller]
     action = route.requirements[:action]
     value = "* URI Pattern: `#{route.path.spec}`\n* Controller#Action: `#{controller}
     ##{action}`"
     else
     value = "Something else"
     end
     else
     # Other Stuff
     end
     

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144. URL Helper Information
     “rake routes” already knows this info!
     value = ''
     if token && token =~ /^([a-z_]+)(_path|_url)$/
     # check if it's a route helper
     if Rails.application.routes.named_routes.key?($1)
     route = Rails.application.routes.named_routes.get($1)
     controller = route.requirements[:controller]
     action = route.requirements[:action]
     value = "* URI Pattern: `#{route.path.spec}`\n* Controller#Action: `#{controller}
     ##{action}`"
     else
     value = "Something else"
     end
     else
     # Other Stuff
     end
     

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145. Helper Definitions
     

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146. View Slide

147. Route Source Location
     bin/rails routes -E
     [aaron@tc-lan-adapter㷊 ~/g/blogsite (main)]$ bin/rails routes -E
     --[ Route 1 ]--------------------------
     Prefix | users
     Verb | GET
     URI | /users(.:format)
     Controller#Action | users#index
     Source Location | config/routes.rb:6
     --[ Route 2 ]--------------------------
     Prefix |
     Verb | POST
     URI | /users(.:format)
     Controller#Action | users#create
     Source Location | config/routes.rb:6
     --[ Route 3 ]--------------------------
     Prefix | new_user
     Verb | GET
     URI | /users/new(.:format)
     Controller#Action | users#new
     Source Location | config/routes.rb:6
     Rails 7.1!
     

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148. Route Source Location
     Language Server Lookup
     if Rails.application.routes.named_routes.key?($1)
     route = Rails.application.routes.named_routes.get($1)
     file, line = route.source_location.split(':')
     file = File.join(@root, file)
     char = File.readlines(file)[line.to_i - 1].index(/[^\s]/)
     uri = "file://" + file
     result = {
     :uri => uri,
     :range => {
     start: { line: line.to_i - 1, character: char },
     end: { line: line.to_i, character: 0 }
     }
     }
     writer.write(id: request[:id], result: result)
     end
     Find the
     source line
     Figure out
     the column
     Send info
     back to editor
     

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149. Error Information
     

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150. ERB is converted to Ruby
     Exceptions in the generated code must be mapped to the source
     <%= notice %>
     Users
     
     <% @users.each do |user| %>
     <%= render user %>
     
     <%= link_to "Show this user", user %>
     
     <% end %>
     
     <%= link_to "New user", new_user_path %>
     Source ERB
     #coding:ASCII-8BIT
     _erbout = +''; _erbout.<< "".freeze;
     _erbout.<<(( notice ).to_s); _erbout.<< "\n\nUsers
     h1>\n\n\n ".freeze
     ; @users.each do |user| ; _erbout.<< "\n ".freeze
     ; _erbout.<<(( render user ).to_s); _erbout.<< "\n \n
     ".freeze
     ; _erbout.<<(( link_to "Show this user", user ).to_s); _erbout.<<
     "\n \n ".freeze
     ; end ; _erbout.<< "\n\n\n".freeze
     ; _erbout.<<(( link_to "New user", new_user_path ).to_s);
     _erbout.<< "\n".freeze
     ; _erbout
     Evaluated Ruby
     

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156. Thank you Mame!
     

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157. View Slide

158. Language Server Integration
     Simply Monkey Patch Rails! (Sorry Eileen)
     class ActionDispatch::DebugView
     def send_exception ex
     resp = {
     uri: "file://" + ex.file_name,
     diagnostics: [
     "range" => {
     "start" => { "character" => 0, "line" => (ex.line_number.to_i - 1) },
     "end" => { "character" => 65536, "line" => (ex.line_number.to_i - 1) },
     },
     "severity" => 1,
     "message" => ex.message
     ]
     }
     Refreshing::LSP::ERROR_QUEUE << [:error, resp]
     end
     end
     

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159. Language Server Integration Cont.
     Pop off the queue and send to the editor
     Thread.new do
     while item = ERROR_QUEUE.pop
     type, val = *item
     if type == :clear
     subscriber.files.each do |file, version|
     val = { uri: file, version: version, diagnostics: [] }
     writer.write(method: "textDocument/publishDiagnostics", params: val)
     end
     else
     val[:version] = subscriber.files[val[:uri]]
     writer.write(method: "textDocument/publishDiagnostics", params: val)
     end
     end
     end
     

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160. This is a Rube Goldberg Machine
     Ruby Goldberg?
     

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161. My Pitch.
     

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162. View Slide

163. Different Servers Have
     Different Features
     

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166. Rails Should Include a
     Language Server
     

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167. Only One
     

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168. I might not value my time,
     but I highly value yours
     

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169. Thank You!
     

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170. Increased Creativity!
     

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171. Thank You!
     㷉
     

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