HOW TO READ HUGE OPEN SOURCE CODE EASILY

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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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