Slide 1
Slide 1 text
Ruby 2.0 on Rails
in Production
Akira
Matsuda
Slide 2
Slide 2 text
% ruby -v
Who here are already using
Ruby 2.0 in production?
Slide 3
Slide 3 text
% ruby -v
Who here are still using 1.8?
Slide 4
Slide 4 text
No content
Slide 5
Slide 5 text
begin
Slide 6
Slide 6 text
Ruby 2.0 goodness
Performance
Stability
Compatibility
New features
Slide 7
Slide 7 text
Performance
Slide 8
Slide 8 text
No content
Slide 9
Slide 9 text
※ taken from @mirakui's slide at RubyKaigi 2013
https://speakerdeck.com/mirakui/high-performance-rails?slide=7
Slide 10
Slide 10 text
※ taken from @mrkn's slide at OedoRubyKaigi 03
https://speakerdeck.com/mrkn/what-a-hard-work-to-make-the-recipe-
sharing-service-available-on-ruby-1-dot-9-3?slide=128
Slide 11
Slide 11 text
rails command boot time
# ruby 1.9.3p429
% time rails r '1'
rails r '1' 7.00s user 1.67s system 99% cpu 8.701 total
% time rails r '1'
rails r '1' 7.03s user 1.64s system 99% cpu 8.698 total
% time rails r '1'
rails r '1' 7.01s user 1.66s system 99% cpu 8.710 total
# ruby 2.0.0p195
% time rails r '1'
rails r '1' 4.80s user 1.29s system 99% cpu 6.124 total
% time rails r '1'
rails r '1' 4.77s user 1.28s system 99% cpu 6.073 total
% time rails r '1'
rails r '1' 4.78s user 1.29s system 99% cpu 6.099 total
Slide 12
Slide 12 text
Stability
Slide 13
Slide 13 text
Stability
Fact: 2.0.0 was a "stable" release
Slide 14
Slide 14 text
1.9.0 was not
1.9.0: unstable
1.9.1: unstable
1.9.2: stable
1.9.3: stable
2.0.0: stable
2.1.0: stable (?)
Slide 15
Slide 15 text
Stability
2.0.0-p195 was released last
month by @nagachika
Slide 16
Slide 16 text
No content
Slide 17
Slide 17 text
No content
Slide 18
Slide 18 text
Stability
2.0.0 is no more p0 and so
it's ready to use in production
Slide 19
Slide 19 text
Branch Maintenance Policies
1.8.7: maintained by @shyouhei, will be dead soon
1.8.8: no plan
1.9.0: dead
1.9.1: dead
1.9.2: maintained by @yugui, dead (?)
1.9.3: maintained by @unak
1.9.4: no plan
2.0.0: maintained by @nagachika
2.0.1: no plan
2.1.0: managed by @naruse
Slide 20
Slide 20 text
1.9.3
Released by @yugui
Maintained by @unak (aka. usa)
Sponsored by Ruby Association
Slide 21
Slide 21 text
No content
Slide 22
Slide 22 text
No content
Slide 23
Slide 23 text
2.0.0
Released by @mametter (aka.
mame)
Maintained by @nagachika
Slide 24
Slide 24 text
No content
Slide 25
Slide 25 text
No content
Slide 26
Slide 26 text
2.1.0
Would be released by @nalsh
(aka. naruse)
Would be released in December
this year
Slide 27
Slide 27 text
No content
Slide 28
Slide 28 text
"TRICK 2013" in RubyKaigi
Results: http://
www.slideshare.net/mametter/
trick2013-results
Winners: https://github.com/tric/
trick2013
Slide 29
Slide 29 text
@unak (usa)
$ruby.is_a?(Object){|oriented| language}
Slide 30
Slide 30 text
@mametter (mame)
eval$C=%q(at_exit{
open("/dev/dsp","wb"){|g|h=[0]*80
$><<"\s"*18+"eval$C=%q(#$C);S=%:"
(S<
Slide 31
Slide 31 text
Compatibility
Slide 32
Slide 32 text
Compatibility
"100% compatible" (Ruby level)
magic comment
Slide 33
Slide 33 text
No content
Slide 34
Slide 34 text
99.9% compatible
Default Ruby source le
encoding to utf-8 [Feature #6679]
Slide 35
Slide 35 text
Hello!
puts '͜Μʹͪʂ'
Slide 36
Slide 36 text
Hello...?
% ruby -v hello_utf8.rb
ruby 1.8.7 (2012-06-29 patchlevel 370) [i686-darwin12.2.1]
͜Μʹͪʂ
% ruby -v hello_utf8.rb
ruby 1.9.3p429 (2013-05-15 revision 40747) [x86_64-darwin12.3.0]
encoding_utf8.rb:1: invalid multibyte char (US-ASCII)
Slide 37
Slide 37 text
Magic comment
# encoding: utf-8
puts '͜Μʹͪʂ'
Slide 38
Slide 38 text
͜Μʹͪɺ1.9.3!
% ruby -v hello_utf8.rb
ruby 1.9.3p429 (2013-05-15 revision 40747) [x86_64-darwin12.3.0]
͜Μʹͪʂ
Slide 39
Slide 39 text
Hello!
puts '͜Μʹͪʂ'
Slide 40
Slide 40 text
Hello...?
% ruby -v hello_utf8.rb
ruby 1.8.7 (2012-06-29 patchlevel 370) [i686-darwin12.2.1]
͜Μʹͪʂ
% ruby -v hello_utf8.rb
ruby 1.9.3p429 (2013-05-15 revision 40747) [x86_64-darwin12.3.0]
encoding_utf8.rb:1: invalid multibyte char (US-ASCII)
% ruby -v hello_utf8.rb
ruby 2.0.0p195 (2013-05-14 revision 40734) [x86_64-darwin12.3.0]
͜Μʹͪʂ
Slide 41
Slide 41 text
Incompatibility
s = "\xE3\x81\x82"
p s, s.size
Slide 42
Slide 42 text
Incompatibility
% ruby -v encoding_binary.rb
ruby 1.9.3p429 (2013-05-15 revision 40747) [x86_64-darwin12.3.0]
"\xE3\x81\x82"
3
% ruby -v encoding_binary.rb
ruby 2.0.0p195 (2013-05-14 revision 40734) [x86_64-darwin12.3.0]
"͋"
1
Slide 43
Slide 43 text
Tiny Print Debugging Tip
s = "\xE3\x81\x82"
# p s, s.size
p str: s, size: s.size
Slide 44
Slide 44 text
Tiny Print Debugging Tip
% ruby encoding_binary.rb
{:str=>"͋", :size=>1}
(by @yhara: http://route477.net/d/?date=20130206#p01)
Slide 45
Slide 45 text
Compatibility (GC bug)
Ruby 2.0 is so compatible with
1.9.3 that even known bugs are
compatible!
Slide 46
Slide 46 text
"GC.disable_lazy_sweep"
https://gist.github.com/mrkn/
5096076
Slide 47
Slide 47 text
New features
Slide 48
Slide 48 text
New Features
(Re nements)
Module#prepend
Keyword arguments
Enumerable#lazy
Slide 49
Slide 49 text
Re nements
Slide 50
Slide 50 text
No content
Slide 51
Slide 51 text
Module#prepend
Slide 52
Slide 52 text
Module#prepend
Good for Rails plugins
You can replace
alias_method_chain with this
Slide 53
Slide 53 text
AMC
class A
def foo
puts 'foo'
end
end
class A
def foo_with_bar
foo_without_bar
puts ‘bar’
end
alias_method_chain :foo, :bar
end
A.new.foo
#=> foo
bar
Slide 54
Slide 54 text
Module#prepend
class A
def foo; puts 'foo'; end
end
module Bar
def foo
super
puts 'bar'
end
end
class A
prepend Bar
end
A.new.foo
#=> foo
bar
Slide 55
Slide 55 text
Keyword arguments
Slide 56
Slide 56 text
Method#parameters
since 1.9.1
Slide 57
Slide 57 text
Method#parameters
class C
def m(a, b = 1, c = nil) end
end
C.new.method(:m).parameters
#=> [[:req, :a], [:opt, :b], [:opt, :c]]
Slide 58
Slide 58 text
asakusarb/action_args
Slide 59
Slide 59 text
No content
Slide 60
Slide 60 text
Initial implementation
module AbstractController
class Base
def send_action(method_name, *args)
return send method_name, *args unless args.blank?
values =
method(method_name).parameters.map(&:last).map {|k|
params[k]}
send method_name, *values
end
end
end
Slide 61
Slide 61 text
Test Patterns
params = {a: '1', b: '2'}
def m end
#=> []
def m(a) end
#=> ['1']
def m(a = 'a') end
#=> ['1']
def m(c = 'c') end
#=> expected: ['c'], actual: [nil]
Slide 62
Slide 62 text
Don't add to the arguments if (type
== :opt) && !params.has_key?
params = {a: '1', b: '2'}
def m(c = 'c') end
#=> ['c']
def m(a, b) end
#=> ['1', '2']
def m(a, b = 'b') end
#=> ['1', '2']
def m(a, c = 'c') end
#=> ['1', 'c']
def m(a = 'a', b = 'b') end
#=> ['1', '2']
def m(c = 'c', d = 'd') end
#=> ['c', 'd']
def m(c = 'c', a) end
#=> expected: ['c', '1'], actual: ['1']
Slide 63
Slide 63 text
Default value can't be determined in
parse / compile phase
def foo(x = rand(3))
Slide 64
Slide 64 text
RubyVM::InstructionSequence
# warning: Do never use this black magic!!
def foo(x = 'xx', y = :yy, z = 1); end
ary = RubyVM::InstructionSequence.of(method(:foo)).to_a
default_args = ary[11][1]
bytecode = ary[13]
p default_args
#=> [:label_0, :label_4, :label_8, :label_11]
p bytecode
#=> [:label_0, 2, [:putstring, "xx"],
[:setlocal_OP__WC__0, 4], :label_4, [:putobject, :yy],
[:setlocal_OP__WC__0, 3], :label_8,
[:putobject_OP_INT2FIX_O_1_C_], [:setlocal_OP__WC__0,
2], :label_11, [:trace, 8], [:putnil], [:trace, 16],
[:leave]]
Slide 65
Slide 65 text
method.parameters.reverse_each do |type, key|
do the same thing
params = {a: '1', b: '2'}
def m(c = 'c', a) end
=> ['c', '1']
Slide 66
Slide 66 text
We needed to do this because,
Method parameters are just an
Array
So the order matters
It's a pain
I wish if the method parameter is
more like a Hash, labeled by the
de ned method argument names
Slide 67
Slide 67 text
OK, that's called "Keyword arguments"
Slide 68
Slide 68 text
Keyword arguments
# traditional method
def m(a, b = 'b', c = 'c') end
m('1', '2', '3')
# kwargs
def m(a, b: 'b', c: 'c') end
m('1', b: '2', c: '3')
Slide 69
Slide 69 text
Keyword arguments
Optional parameters can be
written as a Hash. Order doesn't
matter
action_args now supports
kwargs, so you can use it in your
controller code
Slide 70
Slide 70 text
kwargs and Rails
Rewriting Rails code using kwargs
More comprehensible API
def foo(options_with_some_unknown_keys_and_defaults = {})
def bar(*values_maybe_or_maybe_not_with_options)
⊗
def foo(x: 1, y: 2, z: 2)
def bar(*values, **options)
Slide 71
Slide 71 text
kwargs and Rails (AS)
# AS/lib/active_support/core_ext/class/attribute_accessors.rb
- def cattr_reader(*syms)
- options = syms.extract_options!
+ def cattr_reader(*syms, instance_reader: true, instance_accessor:
true)
...
- unless options[:instance_reader] == false ||
options[:instance_accessor] == false
+ unless (instance_reader == false) || (instance_accessor ==
false)
Slide 72
Slide 72 text
kwargs and Rails (AMo)
# AMo/lib/active_model/validations/validates.rb
- def validates(*attributes)
- defaults = attributes.extract_options!.dup
+ def validates(*attributes, **defaults)
Slide 73
Slide 73 text
kwargs and Rails (AP)
# AP/lib/action_view/helpers/text_helper.rb
- def cycle(first_value, *values)
- options = values.extract_options!
- name = options.fetch(:name, 'default')
-
+ def cycle(first_value, *values, name: 'default')
Slide 74
Slide 74 text
A pitfall I found
Slide 75
Slide 75 text
kwargs and Rails (:if, :unless)
User.validates_presence_of :name, :if => -> { true }
# AMo/lib/active_model/validations/presence.rb
- def validates_presence_of(*attr_names)
+ def validates_presence_of(*attr_names, if: true, unless:
false, on: nil, strict: nil)
Slide 76
Slide 76 text
:if!?
def m(if: true)
end
Slide 77
Slide 77 text
:if!?
def m(if: true)
if if
...
end
end
#=> "syntax error, unexpected keyword_end"
Slide 78
Slide 78 text
:if!?
def m(if: true)
p if
end
#=> "syntax error, unexpected keyword_end"
Slide 79
Slide 79 text
kwargs and Rails (:end)
Slide 80
Slide 80 text
kwargs and Rails (:end)
# actionpack/lib/action_view/helpers/date_helper.rb
- def build_options(selected, options = {})
- options = {
- leading_zeros: true, ampm: false,
use_two_digit_numbers: false
- }.merge!(options)
-
- start = options.delete(:start) || 0
- stop = options.delete(:end) || 59
- step = options.delete(:step) || 1
- leading_zeros = options.delete(:leading_zeros)
+ def build_options(selected, start: 0, end: 59, step: 1,
leading_zeros: true, ampm: false, use_two_digit_numbers: false)
Slide 81
Slide 81 text
:end!?
def m(end: 'omg')
p end
end
#=> "syntax error, unexpected keyword_end, expecting end-of-input"
Slide 82
Slide 82 text
Enumerable#lazy
Slide 83
Slide 83 text
Enumerable#lazy
"Enumerable#lazy".topics.lazy.each {|it| I.talk it}
Slide 84
Slide 84 text
New Features (internal)
TracePoint
DTrace support
caller_locations
debug_inspector API
Memory inspection features
Slide 85
Slide 85 text
No content
Slide 86
Slide 86 text
debug_inspector API
Slide 87
Slide 87 text
The "debugger" gem
Works on Ruby 1.9
Partly supports 2.0
Own header les
Slide 88
Slide 88 text
We created a new gem
Named it "debugger2"
(ko1 named it. Not me!)
Based on new debugger API
Slide 89
Slide 89 text
Debugger2 gem
"1.0.0.beta2"
Still buggy on Rails
We need to do more debugging
on the debugger...
Slide 90
Slide 90 text
We want debugger!!!
Slide 91
Slide 91 text
end