= validates_date_time
 
If you find this plugin useful, please consider a donation to show your support!
 
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  Email address: jonathan.viney@gmail.com
  
== Instructions
 
This plugin adds the ability to do stricter date and time checking with ActiveRecord.
 
The validators can be used to parse strings into <tt>Date</tt> and <tt>Time</tt> objects as well as restrict
an attribute based on other dates or times.
 
  class Person < ActiveRecord::Base
    validates_date     :date_of_birth
    validates_time     :time_of_birth
    validates_date_time :date_and_time_of_birth
  end
  
Use <tt>:allow_nil</tt> to allow the value to be blank.
 
  class Person < ActiveRecord::Base
    validates_date :date_of_birth, :allow_nil => true
  end
  
== Installation
 
  script/plugin install http://svn.viney.net.nz/things/rails/plugins/validates_date_time 
 
== Supported formats
 
The default for the plugin is to expect dates in day/month/year format. If you are in the
US, you will want to change the default to month/day/year by placing the following in config/environment.rb
 
  ValidatesDateTime.us_date_format = true
  
Date format examples:
 
* 2006-01-01
* 1 Jan 06
* 1 Jan 2006
* 10/1/06
* 1/1/2006
  
Time format examples:
* 1pm
* 10:11
* 12:30pm
* 8am
 
Datetime format examples:
 
* 1 Jan 2006 2pm
* 31/1/06 8:30am
 
== Examples
 
If an attribute value can not be parsed correctly, an error is added: 
 
  p = Person.new
  p.date_of_birth = "1 Jan 2006"
  p.time_of_birth = "5am"
  p.save # true
  
  p.date_of_birth = "30 Feb 2006"
  p.save # false, 30 feb is invalid for obvious reasons
   
  p.date_of_birth = "java is better than ruby"
  p.save # false
  
In the final example, as I'm sure you are aware, the record failed to save not only
because "java is better than ruby" is an invalid date, but more importantly, because the statement is blatantly false. ;) 
 
=== Restricting date and time ranges
 
Using the <tt>:before</tt> and <tt>:after</tt> options you can restrict a date or time value based on other attribute values
and predefined values. You can pass as many value to :before or :after as you like.
 
  class Person
    validates_date :date_of_birth, :before => [:date_of_death, Proc.new { 1.day.from_now_to_date}], :after => '1 Jan 1900'
    validates_date :date_of_death, :before => Proc.new { 1.day.from_now.to_date }
  end
  
  p = Person.new
  p.date_of_birth = '1800-01-01'
  p.save  # false
  p.errors[:date_of_birth] # must be after 1 Jan 1900
  
  p.date_of_death = Date.new(2010, 1, 1)
  p.save  # false
  p.errors[:date_of_death] # must be before <1 day from now>
  
  p.date_of_birth = '1960-03-02'
  p.date_of_death = '2003-06-07'
  p.save  # true
  
You can customise the error messages for dates or times that fall outside the required range. The boundary date will be substituted in for %s. Eg:
 
  class Person
    validates_date :date_of_birth, :after => Date.new(1900, 1, 1), :before => Proc.new { 1.day.from_now.to_date }, :before_message => 'Ensure it is before %s', :after_message => 'Ensure it is after %s'
  end
 
Suggestions, comments, problems are all welcome. You'll find me at jonathan.viney@gmail.com