Rake is a fantastic tool

1. rake
Not your father’s build tool
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2. whatchutalk’nboutwillis
• Where it came from
• What it’s related to
• How to use it
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3. What’s in a name?
• Usually the first thing people learn about
rake is the etymology of the name: “Ruby
Make”.
• But it’s much more than a catchy turn of
phrase.
• It’s a fully featured Build Language. That
almost never existed...
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4. Ruby Version of Make?
• Jim tells the birth of rake as code he never
intended to write.
• It started with a simple itch to scratch...
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5. Jim Thought “What if...”
"What if you could specify the make tasks in Ruby, like this ..."
task "build" do
java_compile(...args, etc ...)
end
"The task function would register "build" as a target to be made,
and the block would be the action executed whenever the build
system determined that it was time to do the build target."
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6. 100 Lines Later
• It worked!
• Rake’s prototype lives in the repo:
doc/proto_rake.rdoc
• But it didn’t have timebased file
dependencies... so back to the text-editor.
• And the rest is in the commit history.
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7. A Build Language
• The basic unit of a build language are tasks.
• A build has source files that it uses to
produce a desired product.
• The two most common other build
languages are make and ant.
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8. Comparison
make ant rake
Imperative Style Imperative Style Dependency Based
External DSL External DSL Internal DSL
Custom Syntax XML based Syntax Ruby Syntax
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9. Imperative Style
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10. Imperative Style
• Both the code_generation methods will be
called during test.
• At best that will waste time.
• At worst that can produce undesired
results.
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11. Dependency Based
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12. Dependency Based
• A dependency based system gives the test
method the power to evaluate what
prerequisites it has.
• Then because ruby can evaluate the code
without running it, it can prepare it to be
run in the correct order that will only run
each task once.
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13. Comparison
make ant rake
Imperative Style Imperative Style Dependency Based
External DSL External DSL Internal DSL
Custom Syntax XML based Syntax Ruby Syntax
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14. External vs Internal DSL
• With make and ant you need to use
external scripts or nasty syntax to be
creative.
• Rake can use full power of Ruby at any
time.
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15. Hello World
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16. Building Blocks of Rake
• task • FileUtils
• file • clean
• directory • clobber
• namespace
• multitask
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17. task
In the DSL of rake, a task is a method that takes
two arguments. The first argument is a hash, and
the second is a block.
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18. task dependencies
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19. file
Rake file tasks are most similar to tasks in make.
They get run only when needed. File tasks are
declared using a string rather than a symbol. The
following file task creates a executable program
(named prog) given two object files name a.o and
b.o.
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20. directory
It is common to need to create directories upon
demand. The directory convenience method is a
short-hand for creating a FileTask that creates the
directory.
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21. directory
The directory method does not accept prerequisites
or actions, but both prerequisites and actions can
be added later.
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22. namespaces
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23. multitask
Multitask can help you save time by running tasks
in your build that are safe to run in parallel.
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24. multitask
It even has the ability to determine any
prerequisites that need to be run before hand. It
will complete this prep_for_copy only once then the
three tasks would begin to run together.
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25. FileUtils
• Use the FileUtils module and rake gives you
the most common filesystem commands:
• cd, pwd, mkdir, mkdir_p, rmdir, ln, ln_s,
ln_sf, cp, cp_r, mv, rm, rm_r, rm_rf, install,
chmod, touch
• Create a map of files with FileList:
• FileList[‘**/*.rb’].each {|f| puts f}
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26. Clean/Clobber
• require 'rake/clean'
• Use a pair of file lists: CLEAN and CLOBBER.
• You can then add items to the file lists with
expressions like CLEAN.include('*.o').
• Remember that the clean task removes everything
in the clean list, and clobber removes everything in
both lists.
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27. Built In Tasks
• GemPackageTask (in Ruby Gems now)
• PackageTask
• RdocTask (in Rdoc now)
• TestTask
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28. Rake & Rails
• The default task for a rails project runs
your test suite.
• If you want to see how the rake tasks you
enjoy with Rails are built search for .rake in
the gem source.
• Because as we all know, Rails is Magic!
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29. rake
• Jim Weirich created in 2003.
• Similar to make and ant. With the power of
Ruby.
• Hope you’ve got some ideas on how you’d
like to use it.
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30. Credits
• Jim Weirich - Rake
http://rake.rubyforge.org/
• Martin Fowler - Using the Rake Build
Language
http://martinfowler.com/articles/rake.html
• Josh Nichols - Rake: The Familiar Stranger
http://vimeo.com/2496890
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31. Thank You
• tyler.bird@gmail.com
• @filmprog
• filmprog.com
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