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Satoshi Tagomori, a.k.a. tagomoris
TokyuRubyձٞ14 - Jul 29, 2023
Avoid Collisions,
Desire Co-existence
Names, Modules, Versions, and NameSpaces
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Satoshi Tagomori (@tagomoris)
Independent developer
Technical Consultant
OSS Maintainer
• Fluentd
• MessagePack / msgpack-ruby
• Norikra, Woothee, …
tagomoris
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https://www.
fl
ickr.com/photos/takkanm/3978417669
Asakusa.rb
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10൪ ϛχνϡΞ͓ͰΜ 11൪ ϩʔετϏʔϑΘ͞ͼϚϦω
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Collisions
in Ruby programs, processes
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Collisions
Names, Modules, Versions
Name Collisions:
No one can use a name in two ways.
Module Collisions:
Modules can be modified, globally, from anywhere.
Version Collisions:
Two different versions of a module can’t be loaded.
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Name Collisions
Two “Tagomori” Problem
😃
Tagomori
module Tagomori
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Name Collisions
Two “Tagomori” Problem
😃
Tagomori
🤪
Tagomori
module Tagomori
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Name Collisions
Many “Matsumoto” Problem
module Matsumoto
🙂
Matsumoto
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Name Collisions
Many “Matsumoto” Problem
module Matsumoto
🙂
Matsumoto
(papa)
😀
Matsumoto
(type)
😝
Matsumoto
(katsyoshi)
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Name Collisions
In Fact: App vs Gem, App vs App, Gem vs Gem
• RoR app classes vs Gem library module names
• RoR app classes vs RoR app classes
• “Con
fi
guration”
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Module Collisions
Module global con
fi
guration changes
module Tagomoris
(@black_magic:false)
User App
code
Dependency
library
.method_call
{result}
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Module Collisions
Module global con
fi
guration changes
module Tagomoris
(@black_magic:true)
User App
code
Dependency
library
.enable_black_magic!
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Module Collisions
Module global con
fi
guration changes
module Tagomoris
(@black_magic:true)
User App
code
Dependency
library
.method_call
{result}
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Module Collisions
In Fact: Oj
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Version Collisions
Tagomoris v2 vs v1
User App
code
module Joker1007
VERSION: 3.1.4
module Tagomoris
VERSION: 1.y.z
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Version Collisions
Tagomoris v2 vs v1
module Tagomoris
VERSION: 2.0.x
User App
code
module Joker1007
VERSION: 3.1.4
module Tagomoris
VERSION: 1.y.z
😱
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Version Collisions
In Fact: Gem Dependency Hell
https://www.activestate.com/blog/dealing-ruby-dependency-con
fl
icts/
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Avoid Collisions
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Desire Co-existence
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NameSpaces
In other words: “Multiverse Ruby”
https://rubykaigi.org/2023/presentations/shioyama.html#day2
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NameSpaces in languages
Many ways, Many hells…
• JavaScript/TypeScript (npm)
• Copy everything, import one-by-one “in past” (download/copy cost …)
• Install once, symbolic links, import one-by-one
• Java (classes w/ FQDN)
• Write once, install once, import locally (name collisions, dependency hell)
• Class loaders (oops….)
• Python (pip)
• Install once, import one-by-one (dependency hell)
• Go
• Install once, import locally (name collisions)
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NameSpace Requirements
What is it?
• One native extension libraries of two versions at a time
Ruby Process
LibraryX
version: a.b.c
“x.so”
LibraryX
version: x.y.z
“x.so”
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“དྷͨ, ݟͨ, …”
“Veni, vidi, vici”
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উͬͨο!
ୈ1෦!
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No, Still on the Way
Native Extensions, Top-level References, Open classes, and…
• Calling C-functions of di
ff
erent gem
• Top-level references
• Enforcing use of ‘::NAME’ to access top-level names
• Silent failures of open class accesses
• Automatic namespace adoptions
• Accessing modules in namespaces without any source code updates
• To be implemented in PoC
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Next Step
More Concerns, More Features, and Agreements
• https://bugs.ruby-lang.org/issues/19744
• “[WIP] Namespace on Read PoC” https://github.com/tagomoris/ruby/pull/1
• and
দߐRubyձٞ10
https://matsue.rubyist.net/matrk10/