TinySweeper

TinySweeper keeps your objects tidy!

It's a handy way to clean attributes on your Rails models, though it's independent of Rails, and can be used in any Ruby project. It gives you a light-weigt way to override your methods and declare how their inputs should be cleaned.

class Sundae
  attr_accessor :ice_cream

  include TinySweeper
  sweep(:ice_cream) { |flavor| flavor.strip.downcase }
end

Now your Sundae toppings will be tidied up:

dessert = Sundae.new
dessert.ice_cream = '   CHOCOlate  '
dessert.ice_cream #=> 'chocolate'. Tidy!

TinySweeper will not bother you about your nil values; they're your job to handle.

Sundae.new.topping = nil  # No topping? TinySweeper won't sweep it.

If lots of attributes need to be swept the same way, you can pass an array of field names:

class Sundae
  attr_accessor :ice_cream, :topping, :nuts

  include TinySweeper
  sweep [:ice_cream, :topping, :nuts] { |item| item.strip.downcase }
end

dessert = Sundae.new
dessert.ice_cream = '   CHOCOlate  '
dessert.topping = ' ButTTERscotCH   '
dessert.nuts = '  CRUSHED peaNUtS  '
dessert.ice_cream #=> 'chocolate'
dessert.topping #=> 'butterscotch'
dessert.nuts #=> 'crushed peanuts'

TinySweeper already knows a few sweeping tricks, and you can ask for them by name:

class Sundae
  attr_accessor :ice_cream

  include TinySweeper
  sweep :ice_cream, :blanks_to_nil
end

dessert = Sundae.new
dessert.ice_cream = ""
dessert.ice_cream #=> nil

You can use as many as you need, and TinySweeper will apply them all, left-to-right:

class Sundae
  attr_accessor :ice_cream

  include TinySweeper
  sweep :ice_cream, :strip, :blanks_to_nil

dessert = Sundae.new
dessert.ice_cream = "   "
dessert.ice_cream #=> nil
end

TinySweeper currently only knows a few tricks...

• blanks_to_nil: turn empty strings into nils
• strip: just like String#strip: removes trailing and leading whitespace
• dumb_quotes: replace Smart Quotes with their simpler siblings
• nbsp: replace non breaking space characters with an empty string

...but you can teach it new ones:

TinySweeper::Brooms.add(:strip_html) { |value| Nokogiri::HTML(value).text }

And you can always combine the built-in tricks with a block:

class Sundae
  ...
  sweep(:topping, :strip, :dumb_quotes) { |topping| topping.downcase }
end

If you have an object with lots of attributes that need cleaning (because, say, they were loaded from the database), you can do that, too:

dessert.sweep_up!
# or:
Sundae.sweep_up!(dessert)

Rails models are clearly the natural use-case for this. So it would make sense to have an easy way to auto-clean up models in a table. We'll see. Right now, this works (though it's slow):

MyModel.find_each do |m|
  m.sweep_up!
  m.save
end

You include the TinySweeper module in your class, and define some sweep-up rules on your class' attributes. It prepends an anonymous module to your class, adds to it a method with the same name that cleans its input according to the sweep-up rule, and then passes the cleaned value to super.

"Why not use after_create or before_save or before_validate callbacks?"

That's one approach, and it's used by nilify_blanks, so it's clearly workable. But it means your data isn't cleaned until the callback runs; TinySweeper cleans your data as soon as it arrives. Also, it requires rails, so you can't use it outside of rails.

The standard:

$ gem install tiny_sweeper

or add to your Gemfile:

gem 'tiny_sweeper'

Help is always appreciated!

• Fork the repo.
• Make your changes in a topic branch. Don't forget your specs!
• Send a pull request.

Please don't update the .gemspec or VERSION; we'll coordinate that when we release an update.