Module: Rep

Defined in:
lib/rep.rb,
lib/rep/version.rb

Defined Under Namespace

Modules: ClassMethods, MashedSupport

Constant Summary collapse

VERSION = 
"0.1.1"

Class Method Summary collapse

Instance Method Summary collapse

Class Method Details

.included(klass) ⇒ Object

All classes that ‘include Rep` are extended with `Forwardable`, given some aliases, endowned with `HashieSupport` if Hashie is loaded, and given a delegate method if it doesn’t already have one.



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# File 'lib/rep.rb', line 36

def self.included(klass)
  klass.extend Forwardable
  klass.extend ClassMethods
  klass.instance_eval {
    class << self
      unless defined?(forward)
        alias forward delegate
      end

      unless defined?(fields)
        alias fields json_fields
      end
    end

    if defined?(Mashed)
      include MashedSupport
    end
  }
end

Instance Method Details

#reset_for_json! ⇒ Object

Since a goal is to be able to share instances, we need an easy way to reset a shared instance back to factory defaults. If you memoize any methods that are not declared as json fields, then overried this method and set any memoized variables to nil, then super.



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# File 'lib/rep.rb', line 61

def reset_for_json!
  self.class.all_json_methods.each do |method_name|
    instance_variable_set(:"@#{method_name}", nil)
  end
end

#to_hash(name = :default) ⇒ Object

All the work of generating a hash from an instance is packaged up in one method. Since fields can be aliases in the format ‘{ :json_key_name => :method_name }`, there is some fancy logic to determine the `field_name` and `method_name` variables.

{ :one => :foo }.to_a # => [[:one, :foo]]

Right now it will raise if either a field doesn’t have a method to provide it’s value or if there are no json fields setup for the particular set (which defaults to ‘:default`).



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# File 'lib/rep.rb', line 76

def to_hash(name = :default)
  if fields = self.class.json_fields(name)
    fields.reduce({}) do |memo, field|
      field_name, method_name = field.is_a?(Hash) ? field.to_a.first : [field, field]
      begin
        memo[field_name] = send(method_name)
      rescue NoMethodError => e
        message = "There is no method named '#{method_name}' for the class '#{self.class}' for the '#{name}' list of fields : #{e.message}"
        raise NoMethodError.new(message, method_name, e.args)
      end
      memo
    end
  else
    raise "There are no json fields under the name: #{name}"
  end
end

#to_json ⇒ Object 



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# File 'lib/rep.rb', line 93

def to_json
  JSON.generate(to_hash)
end