Framework Development.pdf

Transcript

1. Framework Development
2. Application Development
3. Spectrum
4. Spectrum First App
5. Spectrum First App Rails
6. Spectrum First App Procore Rails
7. Spectrum First App Procore Strobe Rails
8. Apps Often Include Frameworks
10. The difference between app and framework development is actually a state of mind.
11. My Code
12. Upstream My Code
13. Upstream My Code Downstream
14. Upstream My Code App Development
15. Upstream My Code Downstream Framework Development
16. Upstream
17. Understand Your Upstream
18. Ruby Rails Downstream Framework Development
19. Ruby Rails Downstream Framework Development When doing framework development, go beyond the abstractions presented.
20. Ruby Threads
21. "Threads Are Slow"
22. "Events Are Hot"
23. "YUNO Use Fibers"
24. "YUNO Use Goliath"
25. def hello(y) y += 1 sleep y puts y end x = 1 hello(x) puts "done"
26. __script__ def hello(y) y += 1 sleep y puts y end x = 1 hello(x) puts "done" Name Value x
27. __script__ Name Value x def hello(y) y += 1 sleep y puts y end x = 1 hello(x) puts "done"
28. __script__ Name Value x 1 def hello(y) y += 1 sleep y puts y end x = 1 hello(x) puts "done"
29. hello __script__ Name Value y 1 def hello(y) y += 1 sleep y puts y end x = 1 hello(x) puts "done"
30. hello __script__ Name Value y 2 def hello(y) y += 1 sleep y puts y end x = 1 hello(x) puts "done"
31. hello __script__ Name Value y 2 def hello(y) y += 1 sleep y puts y end x = 1 hello(x) puts "done" Name Value x 1 "the stack"
32. Scheduler "resume this in 2 seconds" hello __script__ Name Value y 2 def hello(y) y += 1 sleep y puts y end x = 1 hello(x) puts "done" Name Value x 1
33. hello __script__ Name Value y 2 def hello(y) y += 1 sleep y puts y end x = 1 hello(x) puts "done"
34. __script__ def hello(y) y += 1 sleep y puts y end x = 1 hello(x) puts "done" Name Value x 1
35. def hello(y) y += 1 sleep y puts y end x = 1 hello(x) puts "done"
36. Stacks Give Us Stack Traces
37. Stacks Give Us Deferred Return
38. __SCRIPT__ def read(file) File.read(file) end file = "README" body = read(file) puts body Name Value file body
39. __SCRIPT__ def read(file) File.read(file) end file = "README" body = read(file) puts body Name Value file "README" body
40. read __SCRIPT__ def read(file) File.read(file) end file = "README" body = read(file) puts body Name Value file "README"
41. read __SCRIPT__ def read(file) File.read(file) end file = "README" body = read(file) puts body Name Value file "README" Name Value file "README" body
42. Scheduler "resume this when the file is ready to read" read __SCRIPT__ def read(file) File.read(file) end file = "README" body = read(file) puts body Name Value file "README" Name Value file "README" body
43. Scheduler "resume this when the file is ready to read" read __SCRIPT__ def read(file) File.read(file) end file = "README" body = read(file) puts body Name Value file "README" Name Value file "README" body The File.read method takes care of returning the actual value once the thread resumes.
44. read __SCRIPT__ def read(file) File.read(file) end file = "README" body = read(file) puts body Name Value file "README"
45. __SCRIPT__ def read(file) File.read(file) end file = "README" body = read(file) puts body Name Value file "README" body <file text>
46. def read(file) File.read(file) end file = "README" body = read(file) puts body
47. Scheduler
48. Manages Multiple Stacks
49. def read(file) File.read(file) end d = "/Users" t1 = Thread.new do f = "#{d}/README" read(file) end t2 = Thread.new do f = "#{d}/.vimrc" read(file) end puts t1.value puts t2.value __SCRIPT__
50. __SCRIPT__ def read(file) File.read(file) end d = "/Users" t1 = Thread.new do f = "#{d}/README" read(file) end t2 = Thread.new do f = "#{d}/.vimrc" read(file) end puts t1.value puts t2.value main
51. __SCRIPT__ def read(file) File.read(file) end d = "/Users" t1 = Thread.new do f = "#{d}/README" read(file) end t2 = Thread.new do f = "#{d}/.vimrc" read(file) end puts t1.value puts t2.value __SCRIPT__ main t1
52. Scheduler "resume this when you have a second" def read(file) File.read(file) end d = "/Users" t1 = Thread.new do f = "#{d}/README" read(file) end t2 = Thread.new do f = "#{d}/.vimrc" read(file) end puts t1.value puts t2.value __SCRIPT__ t1 Name Value d "/Users"
53. __SCRIPT__ def read(file) File.read(file) end d = "/Users" t1 = Thread.new do f = "#{d}/README" read(file) end t2 = Thread.new do f = "#{d}/.vimrc" read(file) end puts t1.value puts t2.value __SCRIPT__ main t1 __SCRIPT__ t2
54. Scheduler "resume this when you have a second" def read(file) File.read(file) end d = "/Users" t1 = Thread.new do f = "#{d}/README" read(file) end t2 = Thread.new do f = "#{d}/.vimrc" read(file) end puts t1.value puts t2.value __SCRIPT__ t2 Name Value d "/Users"
55. Scheduler def read(file) File.read(file) end d = "/Users" t1 = Thread.new do f = "#{d}/README" read(file) end t2 = Thread.new do f = "#{d}/.vimrc" read(file) end puts t1.value puts t2.value __SCRIPT__ t2 Name Value d "/Users" def read(file) File.read(file) end d = "/Users" t1 = Thread.new do f = "#{d}/README" read(file) end t2 = Thread.new do f = "#{d}/.vimrc" read(file) end puts t1.value puts t2.value __SCRIPT__ t1 Name Value d "/Users" __SCRIPT__ def read(file) File.read(file) end d = "/Users" t1 = Thread.new do f = "#{d}/README" read(file) end t2 = Thread.new do f = "#{d}/.vimrc" read(file) end puts t1.value puts t2.value main Name Value d "/Users" active thread inactive threads
56. __SCRIPT__ def read(file) File.read(file) end d = "/Users" t1 = Thread.new do f = "#{d}/README" read(file) end t2 = Thread.new do f = "#{d}/.vimrc" read(file) end puts t1.value puts t2.value __SCRIPT__ main t1 __SCRIPT__ t2
57. Scheduler "resume this when t1 finishes" __SCRIPT__ def read(file) File.read(file) end d = "/Users" t1 = Thread.new do f = "#{d}/README" read(file) end t2 = Thread.new do f = "#{d}/.vimrc" read(file) end puts t1.value puts t2.value main Name Value d "/Users"
58. Scheduler __SCRIPT__ def read(file) File.read(file) end d = "/Users" t1 = Thread.new do f = "#{d}/README" read(file) end t2 = Thread.new do f = "#{d}/.vimrc" read(file) end puts t1.value puts t2.value main Name Value d "/Users" active thread inactive threads def read(file) File.read(file) end d = "/Users" t1 = Thread.new do f = "#{d}/README" read(file) end t2 = Thread.new do f = "#{d}/.vimrc" read(file) end puts t1.value puts t2.value __SCRIPT__ t1 Name Value d "/Users" def read(file) File.read(file) end d = "/Users" t1 = Thread.new do f = "#{d}/README" read(file) end t2 = Thread.new do f = "#{d}/.vimrc" read(file) end puts t1.value puts t2.value __SCRIPT__ t2 Name Value d "/Users"
59. Scheduler def read(file) File.read(file) end d = "/Users" t1 = Thread.new do f = "#{d}/README" read(file) end t2 = Thread.new do f = "#{d}/.vimrc" read(file) end puts t1.value puts t2.value __SCRIPT__ t1 Name Value d "/Users" active thread inactive threads def read(file) File.read(file) end d = "/Users" t1 = Thread.new do f = "#{d}/README" read(file) end t2 = Thread.new do f = "#{d}/.vimrc" read(file) end puts t1.value puts t2.value __SCRIPT__ t2 Name Value d "/Users" __SCRIPT__ def read(file) File.read(file) end d = "/Users" t1 = Thread.new do f = "#{d}/README" read(file) end t2 = Thread.new do f = "#{d}/.vimrc" read(file) end puts t1.value puts t2.value main Name Value d "/Users"
60. __SCRIPT__ def read(file) File.read(file) end d = "/Users" t1 = Thread.new do f = "#{d}/README" read(file) end t2 = Thread.new do f = "#{d}/.vimrc" read(file) end puts t1.value puts t2.value __SCRIPT__ main t1 __SCRIPT__ t2
61. __SCRIPT__ def read(file) File.read(file) end d = "/Users" t1 = Thread.new do f = "#{d}/README" read(file) end t2 = Thread.new do f = "#{d}/.vimrc" read(file) end puts t1.value puts t2.value __SCRIPT__ main t1 __SCRIPT__ t2
62. __SCRIPT__ def read(file) File.read(file) end d = "/Users" t1 = Thread.new do f = "#{d}/README" read(file) end t2 = Thread.new do f = "#{d}/.vimrc" read(file) end puts t1.value puts t2.value read __SCRIPT__ main t1 __SCRIPT__ t2
63. Scheduler "resume this when the file is ready to read" def read(file) File.read(file) end d = "/Users" t1 = Thread.new do f = "#{d}/README" read(file) end t2 = Thread.new do f = "#{d}/.vimrc" read(file) end puts t1.value puts t2.value read __SCRIPT__ t1 Name Value d "/Users" Name Value file "/Users/ README"
64. Scheduler active thread inactive threads def read(file) File.read(file) end d = "/Users" t1 = Thread.new do f = "#{d}/README" read(file) end t2 = Thread.new do f = "#{d}/.vimrc" read(file) end puts t1.value puts t2.value __SCRIPT__ t2 Name Value d "/Users" __SCRIPT__ def read(file) File.read(file) end d = "/Users" t1 = Thread.new do f = "#{d}/README" read(file) end t2 = Thread.new do f = "#{d}/.vimrc" read(file) end puts t1.value puts t2.value main Name Value d "/Users" def read(file) File.read(file) end d = "/Users" t1 = Thread.new do f = "#{d}/README" read(file) end t2 = Thread.new do f = "#{d}/.vimrc" read(file) end puts t1.value puts t2.value read __SCRIPT__ t1 Name Value d "/Users" Name Value file "/Users/ README"
65. __SCRIPT__ def read(file) File.read(file) end d = "/Users" t1 = Thread.new do f = "#{d}/README" read(file) end t2 = Thread.new do f = "#{d}/.vimrc" read(file) end puts t1.value puts t2.value read __SCRIPT__ main t1 __SCRIPT__ t2
66. __SCRIPT__ def read(file) File.read(file) end d = "/Users" t1 = Thread.new do f = "#{d}/README" read(file) end t2 = Thread.new do f = "#{d}/.vimrc" read(file) end puts t1.value puts t2.value read __SCRIPT__ main t1 __SCRIPT__ t2
67. __SCRIPT__ def read(file) File.read(file) end d = "/Users" t1 = Thread.new do f = "#{d}/README" read(file) end t2 = Thread.new do f = "#{d}/.vimrc" read(file) end puts t1.value puts t2.value read __SCRIPT__ main t1 read __SCRIPT__ t2
68. Scheduler "resume this when the file is ready to read" def read(file) File.read(file) end d = "/Users" t1 = Thread.new do f = "#{d}/README" read(file) end t2 = Thread.new do f = "#{d}/.vimrc" read(file) end puts t1.value puts t2.value body __SCRIPT__ t2 Name Value d "/Users" Name Value file "/Users/ README"
69. Scheduler inactive threads __SCRIPT__ def read(file) File.read(file) end d = "/Users" t1 = Thread.new do f = "#{d}/README" read(file) end t2 = Thread.new do f = "#{d}/.vimrc" read(file) end puts t1.value puts t2.value main Name Value d "/Users" def read(file) File.read(file) end d = "/Users" t1 = Thread.new do f = "#{d}/README" read(file) end t2 = Thread.new do f = "#{d}/.vimrc" read(file) end puts t1.value puts t2.value body __SCRIPT__ t2 Name Value d "/Users" Name Value file "/Users/ README" def read(file) File.read(file) end d = "/Users" t1 = Thread.new do f = "#{d}/README" read(file) end t2 = Thread.new do f = "#{d}/.vimrc" read(file) end puts t1.value puts t2.value read __SCRIPT__ t1 Name Value d "/Users" Name Value file "/Users/ README" waiting for IO to be ready waiting for t1 to finish waiting for IO to be ready
70. Threads Abstract Callback Spaghetti
71. What's in That Stack State?
72. What's in That Stack State? Remember that the stack gives us debuggers, backtraces, and deferred return
73. Fibers Are Small Threads
74. Without Automatic I/O Rules
75. BYOS
76. Bring Your Own Scheduler
77. Threads: 8MB Fibers: 4kb Callbacks: 1 frame
78. In Ruby: Threads: 8MB Fibers: 4kb Callbacks: 1 frame
79. In Node: Callbacks: 1 frame
80. Where Was I?
81. Upstream My Code App Development
82. Upstream My Code App Development As an app developer, use the abstractions provided. Don't try to swap out parts of the stack 'for performance' or any other reason without UNDERSTANDING it.
83. Bug in Upstream
84. Upstream My Code App Development report the bug it's not my problem
85. Framework Developer
86. Framework Developer
87. Framework Developer
88. If You Want Better Upstream
89. Upstream My Code App Development wait complain
90. Framework Development
91. Framework Development
92. Your Own Code
93. Learn By Reading Similar Code
94. CakePHP: copycat
95. CakePHP: copycat Worth skimming to find useful mutations in the copy.
96. CakePHP: copycat Struts: different
97. CakePHP: copycat Struts: different Worth skimming to find useful approaches that can be merged.
98. CakePHP: copycat Struts: different Django: similar
99. CakePHP: copycat Struts: different Django: similar Worth reading in depth. Form Models are very interesting.
100. Downstream
101. Downstream Package up your code for other people who will look at you as *their* upstream.
102. Interfaces
103. Downstream Interfaces ActiveModel ActionPack
104. Downstream Interfaces ActiveModel ActionPack Rails Users
105. App Developer Your App
106. Framework Developer Your App Your Tests
107. Framework Developer Your App Your Tests
108. Framework Developer Internal Libraries Your App Your Tests
109. Encapsulate Interfaces
111. Where are the Boundaries?
112. Where are the Boundaries? Corey Haines talked about this a bit yesterday.
113. Framework Development is All About Boundaries
114. Coupling Django Style
115. “ Mark Ramm Turbogears I’m hard on the Django folks here because I think the “tightly integrated/loosely coupled” buzz phrase is actually detrimental to understanding how the trade-off’s work. And there are trade-offs and those trade-offs mean that there isn’t and will never be one perfect web-framework which somehow magically isn’t subject to the down-side of any of the constraints and design trade-offs that we all have to deal with every day.
116. If You Isolate Concerns, Define Interfaces
117. If You Isolate Concerns, Define Interfaces Specifically, think about how the isolated bits communicate with each other
118. What's the Escape Velocity?
119. What's the Escape Velocity? Complexity is pushed up the abstraction chain. Single systems shove it all into one place. Isolating concerns moves it to the links between the concerns. Too many isolated concerns at the same level of abstraction reintroduce complexity.
120. big complex program
122. Now You Have 2 Problems
124. The Tradeoff is Thinking About the Arrows
125. Framework Developer ActiveModel ActionPack Rails Users ?
126. Framework Developer Libraries Your App Your Tests
127. Packaging for Downstream
128. Document Interfaces
129. Internally
131. Publicly
133. You Should
134. Pick a Side, We're at War
135. Pick a Side, We're at War App Developer Framework Developer Upstream Pure Abstraction Participant Your Code You Live Here Learn from Similar Codebases Downstream N/A Package Abstractions and Interfaces
136. You Should: Go All the Way
137. ͋Γ͕ͱ͏ʂ @wycats profiles.google.com/wycats http://yehudakatz.com
138. Questions?