Rails ActiveSupport扩展了to_date，to_datetime，to_time

Question

The application I'm working with insists on displaying all user-input dates (via jquery datepicker) in the non standard American %m/%d/%Y format. As a result we have a lot of strptime methods scattered throughout our controllers.

I'm trying to clean it up and would like to overload the Rails to_date, to_datetime, and to_time extensions so these are no longer necessary.

#config/initializers/string.rb

class String 
  def to_date
    begin
      Date.strptime(self, '%m/%d/%Y') #attempt to parse in american format
    rescue ArgumentError
      Date.parse(self, false) unless blank? #if an error, execute original Rails to_date
                                            #(pulled from Rails source)
    end
  end

  def to_datetime
    begin
      DateTime.strptime(self,'%m/%d/%Y')
    rescue ArgumentError
      DateTime.parse(self, false) unless blank?
    end
  end

  def to_time(form = :local)
    begin
      Time.strptime(self,'%m/%d/%Y')
    rescue ArgumentError
      parts = Date._parse(self, false)
      return if parts.empty?

     now = Time.now
     time = Time.new(
      parts.fetch(:year, now.year),
      parts.fetch(:mon, now.month),
      parts.fetch(:mday, now.day),
      parts.fetch(:hour, 0),
      parts.fetch(:min, 0),
      parts.fetch(:sec, 0) + parts.fetch(:sec_fraction, 0),
      parts.fetch(:offset, form == :utc ? 0 : nil)
     )

     form == :utc ? time.utc : time.getlocal
   end
 end

end

Anyway, this works great in rails console; "06/24/2014".to_date and variants behave exactly as I would like them. However, it looks like ActiveRecord doesn't use these overloaded definitions when creating/validating new table entries, eg

MyModelName.create(start_date:"06/07/2014") gives a start date of 2014-07-06.

What can I do to make ActiveRecord recognize these overloaded definitions?

Answer 1

You can set default time and date formats in config/application.rb file this way:

my_date_formats = { :default => '%d.%m.%Y' }
Time::DATE_FORMATS.merge!(my_date_formats) 
Date::DATE_FORMATS.merge!(my_date_formats)

Answer 2

The ruby-american_date gem may be what you want. It forces Date/DateTime/Time.parse to parse American formatted dates. Simply include it in your project's Gemfile.