Question

I have an ActiveRecord model Account :

class Account < ActiveRecord::Base

  attr_accessible :msisdn

  validates_uniqueness_of :msisdn, :on => :create, 
    :message => "User Already Registered ."
end

And I have a controller which try to create an account :

begin
  account = Account.create!(:msisdn => user)   
rescue Exception => e
  $LOG.error "Account #{user} : --> #{e.message}"  
end

Now the e.message always return : Validation failed: Msisdn User Already Registered, how am I supposed just to get just the message alone like User Already Registered. please note that I’m not using views at all, I want to use it from controller, and I’m using Rails 3.

Thanks in advance

Answer 1

When valid? is called on any model (which happens from create/save/update_attributes) it populates an errors object on the model. Of course if you use a bang method (create!) then the assignment will never happen, so use a non bang method instead. See 3rd code snippet.

account = Account.new(:msisdn => user)
unless account.save #
  # account.errors will be populated with errors
  puts account.errors[:msisdn] # => ['User Already Registered']
end

Alternative using a bang method

account = Account.new(:msisdn => user)
begin
  account.save!
rescue Exception
  puts account.errors[:msisdn]
end

Edit:

Another alternative after looking at the rails api docs is to get the record from the exception as it stores a copy. This makes my original statement false.

ActiveRecord::RecordInvalid
(github)

begin
  account = Account.create!(:msisdn => user)
rescue ActiveRecord::RecordInvalid => e
  puts e.record.errors[:msisdn] # => ['User Already Registered']
end