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HOW TO READ HUGE
OPEN SOURCE CODE EASILY
@yhirano55 at RailsConf 2019
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self.inspect
➤Yoshiyuki Hirano from JAPAN
➤GitHub: @yhirano55
➤Twitter: @yoshi_hirano
➤Rails Contributors #62
➤I’m chief organizer of “Railsdm”
➤I love Rails community
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Have you ever read
Ruby on Rails
source code?
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MORE QUESTIONS
➤Do you know the request/response
Lifecycle of Rails application?
➤Do you know the steps of Active Record's
create, update, validate, and destroy?
➤Do you know the processing of
initialization of Rails application?
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I do not think many
of them actually do
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To tell the truth,
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I have not, too
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I guess we don't
have much time
and patience
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Yesterday, I was impressed by Skylight’s sponsor talk.
The design of the rack application is really elegant
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AND..
➤I want to read the code of its lifecycle of
Rails application
➤But I don't want to spend much time to
trace the code
➤I want to read source code easily. What
would you do?
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Finally, I've shipped
a new RubyGem this morning
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yhirano55/trace_location
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DEMO
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At first, boot rails console, and set request env
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And execute `Rails.application.call(env)`
inside `TraceLocation.trace` block
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Then it generates a log file
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It’s traced locations about `Rails.application.call(env)`
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It’s traced locations about `Rails.application.call(env)`
CALL on rails/engine.rb:522 #call
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It’s traced locations about `Rails.application.call(env)`
CALL on rails/application.rb:607 #build_request
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It helps you can get tracing the
processing of the Lifecycle of
Rails application easily!!
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HOW IT WORK?
➤Use TracePoint that is a Ruby standard
API
➤TracePoint API is one of the BLACK
MAGIC in Ruby
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IMPLEMENTATION
This is TracePoint
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IMPLEMENTATION
Collect logs
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IMPLEMENTATION
Trace events while block call
And disable when it finished
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In making this gem, I used
TracePoint for the first time. It
makes me really feel so good!!
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It helps you get deeply
understanding Ruby on Rails
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It's my pleasure to help you
enjoy Ruby on Rails
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self.inspect
➤Yoshiyuki Hirano from JAPAN
➤GitHub: @yhirano55
➤Twitter: @yoshi_hirano
➤Rails Contributors #62
➤I’m chief organizer of “Railsdm”
➤I love Rails community
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We’re going to have a new
Ruby on Rails conference
The name is…
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RailsKaigi 2020
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We hope you join
RailsKaigi 2020 in
Japan
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yhirano55/trace_location
Thank you so much