Module: KVC

Defined in:
lib/kvc.rb

Overview

KVC (Key-Value Configuration) provides a powerful, transparent way to maintain mutable app settings in the database.

KVC.key = "value" # Saves key-value pairing to a database record.
KVC.key           # Retrieves the record and returns the "value".

Use the index syntax to avoid conflicts with Module methods:

KVC.name = "Ruby Inside"
KVC.name    # => "KVC" (Whoops.)
KVC["name"] # => "Ruby Inside"

Or set boolean methods (values are serialized, so booleans are fair game):

KVC["display_warning?"] = true
KVC.display_warning? # => true

Or get creative:

KVC["Chad's expensive guitar"] = Fender::Stratocaster.new(1957)

By default, nonexistent keys return nil values, but you can be stricter if you want to avoid typo-based bugs:

KVC.a_typo_could_occur?            # => nil
KVC::Settings.strict_keys = true   #
KVC.a_typo_could_occur?            # Raises NoMethodError.

If you really need validations, define them in an initializer. E.g.:

# config/initializers/kvc_config.rb
KVC::Settings.config do
  validates("password") { |value| value =~ /\d+/ }
end

Failed validations will raise ActiveRecord::RecordInvalid.

Defined Under Namespace

Classes: Settings, SettingsProxy

Constant Summary collapse

VERSION = 
"0.1.0"

Class Method Summary collapse

Class Method Details

.[](key) ⇒ Object 



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# File 'lib/kvc.rb', line 41

def [](key)
  if setting = KVC::Settings.find_by_key(key.to_s)
    KVC::SettingsProxy.new setting
  elsif KVC::Settings.strict_keys?
    raise NoMethodError,
      "undefined method `#{key}' for #{self}:#{self.class}"
  end
end

.[]=(key, value) ⇒ Object 



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# File 'lib/kvc.rb', line 50

def []=(key, value)
  setting = KVC::Settings.find_or_initialize_by_key key.to_s
  setting.update_attributes! :value => value
end