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HOW TO READ HUGE OPEN SOURCE CODE EASILY
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yhirano55
May 01, 2019
Technology
3
780
HOW TO READ HUGE OPEN SOURCE CODE EASILY
for RailsConf 2019 LT
yhirano55
May 01, 2019
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Transcript
HOW TO READ HUGE OPEN SOURCE CODE EASILY @yhirano55 at
RailsConf 2019
self.inspect ➤Yoshiyuki Hirano from JAPAN ➤GitHub: @yhirano55 ➤Twitter: @yoshi_hirano ➤Rails
Contributors #62 ➤I’m chief organizer of “Railsdm” ➤I love Rails community
Have you ever read Ruby on Rails source code?
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?
I do not think many of them actually do
To tell the truth,
I have not, too
I guess we don't have much time and patience
Yesterday, I was impressed by Skylight’s sponsor talk. The design
of the rack application is really elegant
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?
Finally, I've shipped a new RubyGem this morning
yhirano55/trace_location
DEMO
At first, boot rails console, and set request env
And execute `Rails.application.call(env)` inside `TraceLocation.trace` block
Then it generates a log file
It’s traced locations about `Rails.application.call(env)`
It’s traced locations about `Rails.application.call(env)` CALL on rails/engine.rb:522 #call
It’s traced locations about `Rails.application.call(env)` CALL on rails/application.rb:607 #build_request
It helps you can get tracing the processing of the
Lifecycle of Rails application easily!!
HOW IT WORK? ➤Use TracePoint that is a Ruby standard
API ➤TracePoint API is one of the BLACK MAGIC in Ruby
IMPLEMENTATION This is TracePoint
IMPLEMENTATION Collect logs
IMPLEMENTATION Trace events while block call And disable when it
finished
In making this gem, I used TracePoint for the first
time. It makes me really feel so good!!
It helps you get deeply understanding Ruby on Rails
It's my pleasure to help you enjoy Ruby on Rails
self.inspect ➤Yoshiyuki Hirano from JAPAN ➤GitHub: @yhirano55 ➤Twitter: @yoshi_hirano ➤Rails
Contributors #62 ➤I’m chief organizer of “Railsdm” ➤I love Rails community
We’re going to have a new Ruby on Rails conference
The name is…
RailsKaigi 2020
We hope you join RailsKaigi 2020 in Japan
yhirano55/trace_location Thank you so much