Micro Libraries FTW

Transcript

1. Micro Libraries FTW
   Piotr Solnica
   wroclove.rb 2014
   

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2. Who am I?
   Ruby and Rails developer
   OSS ruby hacker
   github.com/solnic
   @_solnic_
   

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3. Ruby Object Mapper
   github.com/rom-rb
   

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4. Agenda
   Big libraries vs micro libraries
   Micro libraries and frameworks
   Example micro libraries
   microrb.com
   

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5. Big Libraries
   vs
   Micro Libraries
   

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6. BIG LIBRARIES MICRO LIBRARIES
   Solving many problems Solving just one problem
   Big LOC Small LOC
   Wide interfaces Narrow interfaces
   High churn even after 1.0 Low churn especially after 1.0
   

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7. Rails Influence
   

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8. Ruby developers
   <3
   Rails
   

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9. Rails has a huge impact on
   how we write Ruby
   

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10. Rails is in favor of huge libraries
    ActiveSupport and a wide adoption of monkey-
    patching
    ActiveRecord-like style - one object with a
    plethora of responsibilities and mixing seemingly
    related concerns
    

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11. Rails is great but
    let’s move on
    

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12. Let’s embrace
    Unix philosophy
    

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13. “Many UNIX programs do quite trivial things
    in isolation, but, combined with other
    programs, become general and useful tools”
    The UNIX Programming Environment
    

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14. Micro Libraries FTW
    

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15. Why building a micro library?
    

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16. Complex functionality that could be reused
    Constantly repeated design pattern
    A specific problem known up front
    

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17. Building frameworks based on
    micro libraries
    

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18. bottom-up
    vs
    top-down
    

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19. bottom-up
    Really great when you know
    exactly what you’re doing
    

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20. Does not happen
    very often
    

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21. top-down
    Really great even when you
    don’t know exactly what
    you’re doing
    

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22. Happens almost
    all the time
    

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23. Unfortunately top-down approach
    can be misleading
    

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24. DSL + core domain logic
    ==
    disaster
    

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25. Frameworks should provide high-level
    interfaces that are built on top of
    lower level micro libraries
    

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26. Challenges
    

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27. Dealing with
    many dependencies
    is hard
    

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28. rubygems + bundler = slow
    “meta-gems”
    PANIC when seeing lots of gems being installed
    

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29. Dependency Hell
    

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30. 2 gems depending on different versions of
    another gem
    ==
    HELL
    

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31. Version conflicts between
    frameworks are the biggest
    challenge
    

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32. Semantic Versioning
    

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33. Be responsible!
    

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34. Changelogs
    

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35. Tools can help!
    

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36. ruby-toolbox.com
    lots of information about gems
    gemnasium.com
    detailed information about dependencies of gems
    

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37. Example micro libraries
    

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38. github.com/dkubb/equalizer
    

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39. require "equalizer"!
    !
    class GeoLocation!
    include Equalizer.new(:lat, :lng)!
    !
    attr_reader :lat, :lng!
    !
    def initialize(attributes)!
    @lat, @lng = attributes.values_at(:lat, :lng)!
    end!
    end!
    !
    loc1 = GeoLocation.new(:lat => 123, :lng => 321)!
    loc2 = GeoLocation.new(:lat => 123, :lng => 321)!
    !
    loc1 == loc2 # true!
    !
    loc1.inspect!
    => #
    

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40. github.com/mbj/anima
    

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41. equalizer + anima
    

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42. require "anima"!
    !
    class GeoLocation!
    include Anima.new(:lat, :lng)!
    end!
    !
    loc1 = GeoLocation.new(:lat => 123, :lng => 321)!
    loc2 = GeoLocation.new(:lat => 123, :lng => 321)!
    !
    loc1 == loc2!
    # => true
    

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43. virtus + equalizer
    

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44. require "virtus"!
    !
    class GeoLocation!
    include Virtus.value_object!
    !
    values do!
    attribute :lat, Float!
    attribute :lng, Float!
    end!
    end!
    !
    loc1 = GeoLocation.new(:lat => "123", :lng => "321")!
    loc2 = GeoLocation.new(:lat => "123", :lng => "321")!
    !
    loc1 == loc2!
    # => true
    

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45. How about a framework?
    

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46. Ruby Object Mapper
    github.com/rom-rb/rom
    

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47. morpher
    github.com/mbj/morpher
    

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48. rom + morpher
    

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49. module ROM!
    class Mapper!
    !
    # Abstract loader class!
    #!
    # @private!
    class Loader!
    !
    # some stuff is here!
    !
    # @api public!
    def call(tuple)!
    transformer.call(tuple)!
    end!
    !
    end # Loader!
    !
    end # Mapper!
    end # ROM
    This is morpher’s transformer
    and it takes care of everything
    

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50. virtus 2.0 = anima + morpher
    

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51. microrb.com
    

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52. Gather libraries that meet specific criteria
    Make it easy to find the right tool for the job
    Help in connecting maintainers and contributors
    Promote style of development that adheres to the
    unix philosophy
    Promote frameworks that are built on top of micro
    libraries
    

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53. Thank You!
    <3<3<3
    

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