Ruby Batteries Included

As given at MWRC 2013.

Transcript

1. RUBY BATTERIES INCLUDED Ruby Can Standard Library, And So Can You!
2. HOW MANY GEMS DOES IT TAKE TO BUILD AN APP?
3. HOW MANY GEMS DOES IT TAKE TO BUILD AN APP? $ grep gem Gemfile -c
4. HOW MANY GEMS DOES IT TAKE TO BUILD AN APP? $ grep gem Gemfile -c 135
5. THE STANDARD LIBRARY http://ruby-doc.org/
6. CORE VS STD-LIB
7. find `ruby -e 'puts $:.join(" ")'` -iname '*.rb' -exec grep -E '^\w*class ' {} \; | sort | uniq | wc -l
8. find `ruby -e 'puts $:.join(" ")'` -iname '*.rb' -exec grep -E '^\w*class ' {} \; | sort | uniq | wc -l
9. OKAY, NOT ALL OF THEM •Bed Basics •Bath Performance •Beyond Beyond
11. http://www.flickr.com/photos/austinevan/3368444745/
12. Set
13. Set require 'set'
14. Set require 'set' s = Set.new([1, 2, 3, 1, 1, 1]) puts s.inspect # => #<Set: {1, 2, 3}>
15. Enumerable
16. Enumerable class MyFileChanger include Enumerable File = Struct.new(:name, :content) def initialize @files = [] end def <<(filename) content = ::File.read(filename) @files << File.new(filename, content) self end def each @files.each do |file| yield([file.name, file.content]) end end end
17. Enumerable class MyFileChanger include Enumerable File = Struct.new(:name, :content) def initialize @files = [] end def <<(filename) content = ::File.read(filename) @files << File.new(filename, content) self end def each @files.each do |file| yield([file.name, file.content]) end end end files = MyFileChanger.new files << '/etc/profile' << '/etc/bashrc' files.each_with_index do |(name, content), index| puts "#{index}. #{name} is #{content.bytesize} bytes" end names = files.map do |(name, content)| name end puts names.inspect size = files.reduce(0) do |sum, (name, content)| sum + content.bytesize end puts size
18. Enumerable class MyFileChanger include Enumerable File = Struct.new(:name, :content) def initialize @files = [] end def <<(filename) content = ::File.read(filename) @files << File.new(filename, content) self end def each @files.each do |file| yield([file.name, file.content]) end end end files = MyFileChanger.new files << '/etc/profile' << '/etc/bashrc' files.each_with_index do |(name, content), index| puts "#{index}. #{name} is #{content.bytesize} bytes" end names = files.map do |(name, content)| name end puts names.inspect size = files.reduce(0) do |sum, (name, content)| sum + content.bytesize end puts size 0. /etc/profile is 189 bytes 1. /etc/bashrc is 745 bytes ["/etc/profile", "/etc/bashrc"] 934
19. Enumerator
20. Enumerator a = [1, 2, 3] a.each { |n| puts n } Enumerator.new(a).each { |n| puts n }
21. Enumerator a = [1, 2, 3] a.each { |n| puts n } Enumerator.new(a).each { |n| puts n } naturals = Enumerator.new do |y| n = 1 loop do y << n n += 1 end end odds = Enumerator.new do |y| naturals.each do |n| y << n if n % 2 != 0 end end
22. Enumerator a = [1, 2, 3] a.each { |n| puts n } Enumerator.new(a).each { |n| puts n } naturals = Enumerator.new do |y| n = 1 loop do y << n n += 1 end end odds = Enumerator.new do |y| naturals.each do |n| y << n if n % 2 != 0 end end class Integer def prime? return false if self < 2 max = Math.sqrt(self).floor (2..max).none? { |n| self % n == 0 } end end primes = Enumerator.new do |y| y << 2 odds.each do |n| y << n if n.prime? end end
23. Enumerator a = [1, 2, 3] a.each { |n| puts n } Enumerator.new(a).each { |n| puts n } naturals = Enumerator.new do |y| n = 1 loop do y << n n += 1 end end odds = Enumerator.new do |y| naturals.each do |n| y << n if n % 2 != 0 end end class Integer def prime? return false if self < 2 max = Math.sqrt(self).floor (2..max).none? { |n| self % n == 0 } end end primes = Enumerator.new do |y| y << 2 odds.each do |n| y << n if n.prime? end end puts primes.take(10).inspect # => [2, 3, 5, 7, 11, 13, 17, 19, 23, 29]
24. SimpleDelegator
25. SimpleDelegator require 'delegate'
26. SimpleDelegator require 'delegate' class FancyString < SimpleDelegator def fancy? self == 'fancy' end end
27. SimpleDelegator require 'delegate' class FancyString < SimpleDelegator def fancy? self == 'fancy' end end s = FancyString.new('fancy') puts s.fancy? # => true
28. SimpleDelegator require 'delegate' class FancyString < SimpleDelegator def fancy? self == 'fancy' end end s = FancyString.new('fancy') puts s.fancy? # => true puts s.length # => 5
29. Forwardable
30. Forwardable require 'forwardable'
31. Forwardable require 'forwardable' FancyString = Struct.new(:str) do extend Forwardable # Single delegation def_delegator :str, :length, :fancy_length # Multiple delegations def_delegators :str, :include?, :match end
32. Forwardable require 'forwardable' FancyString = Struct.new(:str) do extend Forwardable # Single delegation def_delegator :str, :length, :fancy_length # Multiple delegations def_delegators :str, :include?, :match end s = FancyString.new('Hello!')
33. Forwardable require 'forwardable' FancyString = Struct.new(:str) do extend Forwardable # Single delegation def_delegator :str, :length, :fancy_length # Multiple delegations def_delegators :str, :include?, :match end s = FancyString.new('Hello!') puts s.fancy_length # => 6 puts s.include?('!') # => true
34. Forwardable require 'forwardable' FancyString = Struct.new(:str) do extend Forwardable # Single delegation def_delegator :str, :length, :fancy_length # Multiple delegations def_delegators :str, :include?, :match end s = FancyString.new('Hello!') puts s.fancy_length # => 6 puts s.include?('!') # => true puts s.bytesize # => NoMethodError
36. Benchmark
37. Benchmark require 'benchmark' results = Benchmark.measure do 1_000_000.times { |i| i.to_s } GC.start end puts results # => 0.480000 0.010000 0.490000 ( 0.487643)
38. Benchmark require 'benchmark' results = Benchmark.measure do 1_000_000.times { |i| i.to_s } GC.start end puts results # => 0.480000 0.010000 0.490000 ( 0.487643) n = 5000000 # Simple benchmark Benchmark.bm do |x| x.report { for i in 1..n; a = "1"; end } x.report { n.times do ; a = "1"; end } x.report { 1.upto(n) do ; a = "1"; end } end
39. Benchmark
40. Benchmark # Nice reporting labels Benchmark.bm(10) do |x| x.report('for:') { for i in 1..n; a = "1"; end } x.report('times:') { n.times do ; a = "1"; end } x.report('upto:') { 1.upto(n) do ; a = "1"; end } end # Warmup Benchmark.bmbm(10) do |x| x.report('for:') { for i in 1..n; a = "1"; end } x.report('times:') { n.times do ; a = "1"; end } x.report('upto:') { 1.upto(n) do ; a = "1"; end } end
41. RubyVM http://timelessrepo.com/tailin-ruby
42. RubyVM def acc(i, n, result) if i == -1 result else acc(i - 1, n + result, n) end end def fib(i) acc(i, 1, 0) end puts fib(10000) # => stack level too deep (SystemStackError) http://timelessrepo.com/tailin-ruby
43. RubyVM::InstructionSequence
44. RubyVM::InstructionSequence RubyVM::InstructionSequence.compile_option = { :tailcall_optimization => true, :trace_instruction => false }
45. RubyVM::InstructionSequence RubyVM::InstructionSequence.compile_option = { :tailcall_optimization => true, :trace_instruction => false } RubyVM::InstructionSequence.new(<<-EOF).eval def acc(i, n, result) if i == -1 result else acc(i - 1, n + result, n) end end def fib(i) acc(i, 1, 0) end EOF
46. RubyVM::InstructionSequence RubyVM::InstructionSequence.compile_option = { :tailcall_optimization => true, :trace_instruction => false } RubyVM::InstructionSequence.new(<<-EOF).eval def acc(i, n, result) if i == -1 result else acc(i - 1, n + result, n) end end def fib(i) acc(i, 1, 0) end EOF puts fib(10000) # => A number with 2090 digits
47. Fiddle
48. Fiddle require 'fiddle' include Fiddle
49. Fiddle require 'fiddle' include Fiddle libm = DL.dlopen('/usr/lib/libm.dylib')
50. Fiddle require 'fiddle' include Fiddle libm = DL.dlopen('/usr/lib/libm.dylib') f = libm['sqrt']
51. Fiddle require 'fiddle' include Fiddle libm = DL.dlopen('/usr/lib/libm.dylib') f = libm['sqrt'] args = [TYPE_DOUBLE]
52. Fiddle require 'fiddle' include Fiddle libm = DL.dlopen('/usr/lib/libm.dylib') f = libm['sqrt'] args = [TYPE_DOUBLE] ret = TYPE_DOUBLE
53. Fiddle require 'fiddle' include Fiddle libm = DL.dlopen('/usr/lib/libm.dylib') f = libm['sqrt'] args = [TYPE_DOUBLE] ret = TYPE_DOUBLE sqrt = Function.new(f, args, ret)
54. Fiddle require 'fiddle' include Fiddle libm = DL.dlopen('/usr/lib/libm.dylib') f = libm['sqrt'] args = [TYPE_DOUBLE] ret = TYPE_DOUBLE sqrt = Function.new(f, args, ret) puts sqrt.call(81) # => 9.0
55. WeakRef
56. WeakRef require 'weakref' bightml = WeakRef.new(read_html('http:// bigpage.com/')) puts bightml # => "<html>..." puts bightml.weakref_alive? # => true
57. WeakRef require 'weakref' bightml = WeakRef.new(read_html('http:// bigpage.com/')) puts bightml # => "<html>..." puts bightml.weakref_alive? # => true GC.start
58. WeakRef require 'weakref' bightml = WeakRef.new(read_html('http:// bigpage.com/')) puts bightml # => "<html>..." puts bightml.weakref_alive? # => true GC.start puts bightml.weakref_alive? # => false
59. http://www.flickr.com/photos/bobcanada/4506301467/
60. SecureRandom
61. SecureRandom require 'securerandom'
62. SecureRandom require 'securerandom' puts SecureRandom.base64 # => 9d4va7k0/XhK2EqYMXJ2jg==
63. SecureRandom require 'securerandom' puts SecureRandom.base64 # => 9d4va7k0/XhK2EqYMXJ2jg== puts SecureRandom.hex # => 9e70e038fc7faf20106c304854c21b8a
64. SecureRandom require 'securerandom' puts SecureRandom.base64 # => 9d4va7k0/XhK2EqYMXJ2jg== puts SecureRandom.hex # => 9e70e038fc7faf20106c304854c21b8a puts SecureRandom.random_bytes.inspect # => "r>0\xD1\xA4\x00t&\x82\xFCEl_\x17w\xF1"
65. SecureRandom require 'securerandom' puts SecureRandom.base64 # => 9d4va7k0/XhK2EqYMXJ2jg== puts SecureRandom.hex # => 9e70e038fc7faf20106c304854c21b8a puts SecureRandom.random_bytes.inspect # => "r>0\xD1\xA4\x00t&\x82\xFCEl_\x17w\xF1" puts SecureRandom.random_number # => 0.47149176126339587
66. SecureRandom require 'securerandom' puts SecureRandom.base64 # => 9d4va7k0/XhK2EqYMXJ2jg== puts SecureRandom.hex # => 9e70e038fc7faf20106c304854c21b8a puts SecureRandom.random_bytes.inspect # => "r>0\xD1\xA4\x00t&\x82\xFCEl_\x17w\xF1" puts SecureRandom.random_number # => 0.47149176126339587 puts SecureRandom.random_number(50) # => 37
67. SecureRandom require 'securerandom' puts SecureRandom.base64 # => 9d4va7k0/XhK2EqYMXJ2jg== puts SecureRandom.hex # => 9e70e038fc7faf20106c304854c21b8a puts SecureRandom.random_bytes.inspect # => "r>0\xD1\xA4\x00t&\x82\xFCEl_\x17w\xF1" puts SecureRandom.random_number # => 0.47149176126339587 puts SecureRandom.random_number(50) # => 37 puts SecureRandom.uuid # => 3a34412c-4798-4985-9a43-7d36a6e0d116
68. GServer
69. GServer require 'gserver'
70. GServer require 'gserver' require 'securerandom' class RandomServer < GServer def serve(io) cmd = io.read(4).strip case cmd when 'hex' then io.puts(SecureRandom.hex) when 'uuid' then io.puts(SecureRandom.uuid) end end end
71. GServer require 'gserver' require 'securerandom' class RandomServer < GServer def serve(io) cmd = io.read(4).strip case cmd when 'hex' then io.puts(SecureRandom.hex) when 'uuid' then io.puts(SecureRandom.uuid) end end end server = RandomServer.new(10101) server.start server.join
72. Kernel#spawn
73. Kernel#spawn def capture(cmd) r, w = IO.pipe pid = spawn(cmd, :out => w) w.close Process.wait(pid) r.read ensure r.close end output = capture('randomizer') print output
74. Shellwords
75. Shellwords require 'shellwords'
76. Shellwords require 'shellwords' pattern = '; rm -rf /; ' capture("randomizer #{pattern.shellescape} /dev/*")
77. Shellwords require 'shellwords' pattern = '; rm -rf /; ' capture("randomizer #{pattern.shellescape} /dev/*") # Assuming our capture function could take *args like system
78. Shellwords require 'shellwords' pattern = '; rm -rf /; ' capture("randomizer #{pattern.shellescape} /dev/*") # Assuming our capture function could take *args like system capture('randomizer', pattern, '/dev/*') # => Nope
79. PStore
80. PStore require 'pstore' store = PStore.new('randomizer', thread_safe = true) store.ultra_safe = true
81. PStore require 'pstore' store = PStore.new('randomizer', thread_safe = true) store.ultra_safe = true store.transaction do store['App'] = 'The Randomizer' store[:randoms] ||= [] store[:randoms] << Randomizer.uuid end
82. PStore require 'pstore' store = PStore.new('randomizer', thread_safe = true) store.ultra_safe = true store.transaction do store['App'] = 'The Randomizer' store[:randoms] ||= [] store[:randoms] << Randomizer.uuid end store.transaction do puts store[:randoms].inspect # => ["901dcd24-fa10-4194-b25b-8ad49bc875fb"] end
83. PStore require 'pstore' store = PStore.new('randomizer', thread_safe = true) store.ultra_safe = true store.transaction do store['App'] = 'The Randomizer' store[:randoms] ||= [] store[:randoms] << Randomizer.uuid end store.transaction do puts store[:randoms].inspect # => ["901dcd24-fa10-4194-b25b-8ad49bc875fb"] end store.transaction do store[:randoms] = [] store.abort # Or an Exception end
84. PStore require 'pstore' store = PStore.new('randomizer', thread_safe = true) store.ultra_safe = true store.transaction do store['App'] = 'The Randomizer' store[:randoms] ||= [] store[:randoms] << Randomizer.uuid end store.transaction do puts store[:randoms].inspect # => ["901dcd24-fa10-4194-b25b-8ad49bc875fb"] end store.transaction do store[:randoms] = [] store.abort # Or an Exception end store.transaction do puts store[:randoms].inspect # => ["901dcd24-fa10-4194-b25b-8ad49bc875fb"] end
85. I heard you like testing...
86. I heard you like testing...
87. MiniTest
88. MiniTest require 'minitest/autorun' class MathTest < MiniTest::Unit::TestCase def test_addition assert_equal 2, 1 + 1 end end describe Integer do it 'should subtract' do (1 - 1).must_equal(0) end end
89. MiniTest require 'minitest/autorun' class MathTest < MiniTest::Unit::TestCase def test_addition assert_equal 2, 1 + 1 end end describe Integer do it 'should subtract' do (1 - 1).must_equal(0) end end describe 'Mocks' do it 'should mock things' do mock = MiniTest::Mock.new mock.expect(:length, 10) mock.length.must_equal(10) mock.verify end end
90. Other Fun Things • OptionParser/optparse, GetoptLong/getoptlong • Two command line option parsers! • WEBrick => require ‘webrick’ • Threaded HTTP server. • Rss => require ‘rss’ • Parse and generate RSS feeds. In the stdlib. wat.
91. Other Fun Things • Drb => require ‘drb’ • Distributed object system. • Find => require ‘find’ • Recursively iterate the filesystem. • Ripper => require ‘ripper’ • Parse ruby files
92. Other Fun Things • ThreadsWait => require ‘thwait’ • Wait for a bunch of threads, block called for each when it finishes. • Queue/SizedQueue => require ‘thread’ • << things in, #pop things out. • MonitorMixin => require ‘monitor’ • Thread safety with synchronize block.
93. Other Fun Things • Net::POP3 => require ‘net/pop’ • Talk POP3 email. • Net::IMAP => require ‘net/imap’ • Talk IMAP email. • Net::SMTP => require ‘net/smtp’ • Talk to SMTP servers.
94. Other Fun Things • Net::FTP => require ‘net/ftp’ • Talk FTP • Net::HTTP => require ‘net/http’ • Talk HTTP
96. THANKS!! @darkhelmetlive darkhelmet verboselogging.com GetYardstick.com https://www.makesets.com/the-ruby-standard-library