Set a Date Attribute from date_select Without Mass Assignment in Ruby On Rails

This has been talked about a million times, but I just ran into this problem again and want to share the solution: You have a date_select helper in your Rails view and you want to assign the selected date to your model. With mass assignment that's not a problem, but when you try this:

@something.my_date = params[:something][:my_date]

You will be disappointed and there will be wailing and gnashing of teeth. Why? Because date_select creates 3 form components and 3 corresponding values in the form and in the params[:something] hash, namely

params[:something][:my_date(1i)]
params[:something][:my_date(2i)]
params[:something][:my_date(3i)]

These represent the year, the month and the day (Duh!). When you use @something.attributes= to mass assign this, ActiveRecord takes care of creating a date object from these three values (see attributes=, assign_multiparameter_attributes, extract_callstack_for_multiparameter_attributes, and execute_callstack_for_multiparameter_attributes). Sometimes you might not want to mass assign, though (security comes to mind). So what are you to do? Maybe putting this code (inspired by this code) in your application.rb might help:

  private
 
  def convert_date(hash, date_symbol_or_string)
    attribute = date_symbol_or_string.to_s
    return Date.new(hash[attribute + '(1i)'].to_i, hash[attribute + '(2i)'].to_i, hash[attribute + '(3i)'].to_i)   
  end

Now you can assign dates from date_select like this:

@something.my_date = convert_date(params[:something], :my_date)

Please comment if you have a better or more elegant solution! If this was useful for you, please take a minute and recommend me:

Thank you!

---

Comments