Validation fails - cannot be blank - even though it is not blank

Question

I have a model

class Card < ActiveRecord::Base
  belongs_to :CardColour
  validates :CardColour, presence:true

In the console I type

@a = Card.new(:card_colour_id =1)

However it is not valid. I ask why, by doing @a.errors, and the console tells me

=> #<ActiveModel::Errors:0x000000052e57e8 @base=#<Card id: nil, card_colour_id: 1>, @messages={:CardColour=>["can't be blank"]}>

I've spent hours looking at this, am completely baffled and am at my wits end as to why I can't seemingly do the most simple things in Rails.

I've looked up questions with similar titles, but they all seem to be more complicated scenarios. I have more going on than this example, but nothing more complicated. eg I actually have 3 foreign keys set up, and they all tell me they can't be blank, even if they are populated with valid values.

I have found this answer which suggests my code is correct, and will actually do what I want it to (ie validate that the card_colour_id links to an actual object in the CardColour model).

What does your `CardColour` model look like? You should really try being a bit more idiomatic with Ruby. Try going with `belongs_to :card_colour` and `validates :card_colour_id, presence: true` — Orlando, Jun 16 '16 at 21:52
can you show your associations and migrations as well please? — ruby_newbie, Jun 16 '16 at 21:52
I am rather new but something is rather confusing: CardColour seems to be a proper model , as well as a column that needs to be filled in for the record to be valid. — Maxence, Jun 16 '16 at 22:14
Close, but use `validates :card_colour, presence: true` instead of "card_colour_id". — Michael Chaney, Jun 16 '16 at 22:14
@Orlando I have been trying to be idiomatic. It's frankly confusing. I've edited my question, I made a slight boo-boo — reedstonefood, Jun 16 '16 at 22:43

score 1 · Answer 1 · answered Jun 17 '16 at 14:19

1

You are validating CardColour, but in your console you create a new Card with card_colour_id, but not with CardColour. That is why you get an error.

You should change validates :CardColour, presence :true to validates :your_model's_column, presence :true

answered Jun 17 '16 at 14:19

Alex Zakruzhetskyi

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This works! Thanks! But it seems it will accept any integer as card_colour_id? I thought belongs_to set up a foreign key relationship? – reedstonefood Jun 18 '16 at 22:09

score 0 · Answer 2 · answered Jun 17 '16 at 06:15

0

Please change your model code to

class Card < ActiveRecord::Base
  belongs_to :card_colour
  validates :card_colour_id, presence:true

and your new card line to

@a = Card.new(:card_colour_id => 1)

or with the new syntax

@a = Card.new(card_colour_id: 1)

answered Jun 17 '16 at 06:15

Sebin

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Model class names are supposed to be CamelCase... so belong_to :CardColour is correct is it not? – reedstonefood Jun 18 '16 at 22:13

Validation fails - cannot be blank - even though it is not blank

2 Answers2