Question

Recently I have started to learn Rails.

Now, I’m implementing the Friendship relation in my own project. And here is the code some thing like that (some of them was collected from Internet)

class Friendship < ActiveRecord::Base 

  attr_accessible :friend_id, :message, :user_id, :approved

  validates_uniqueness_of :user_id, :scope => [:friend_id]

  validates :approved, :presence => true
  belongs_to :user
  belongs_to :friend, :class_name => "User", :foreign_key => "friend_id"

end

/////////////////////

class User < ActiveRecord::Base
   has_many :friendships
   has_many :inverse_friendships, :class_name => "Friendship", :foreign_key => "friend_id"
   has_many :direct_friends, :through => :friendships, :conditions => { 'friendships.approved' => true }, :source => :friend
end

//////////////////////

class CreateFriendships < ActiveRecord::Migration
  def change
    create_table :friendships do |t|
    t.integer :user_id
    t.integer :friend_id
    t.text :message
    t.boolean :approved, :default => false

    t.timestamps
  end
end

When I create new Friendship from the console “rails c” it was OK when the approved = true

Friendship.create(:user_id=>7, :friend_id=>11, :approved=>1, :message=>'Be my friend :D')
(0.1ms)  begin transaction
SQL (0.9ms)  INSERT INTO "friendships" ("approved", "created_at", "friend_id", "message", "updated_at", "user_id") VALUES (?, ?, ?, ?, ?, ?)  [["approved", true], ["created_at", Sat, 13 Oct 2012 14:15:36 UTC +00:00], ["friend_id", 11], ["message", "Be my friend :D"], ["updated_at", Sat, 13 Oct 2012 14:15:36 UTC +00:00], ["user_id", 7]]
(12.2ms)  commit transaction

but when I set approved = false, it is down

Friendship.create(:user_id=>6, :friend_id=>7, :approved=>0)
(0.1ms)  begin transaction
(0.1ms)  rollback transaction
=> #<Friendship id: nil, user_id: 6, friend_id: 7, message: nil, approved: false, created_at: nil, updated_at: nil>

For the first time. I have thought it was the database(sqlite3) problem, but when I try this, from the sqlite3 terminal, it was fine

sqlite> insert into friendships (user_id, friend_id, created_at, updated_at) values(11, 6, '2012-10-13 14:15:36', '2012-10-13 14:15:36');
sqlite> select * from friendships;
        id = 1
   user_id = 11
 friend_id = 6
   message = 
  approved = f
created_at = 2012-10-13 14:15:36
updated_at = 2012-10-13 14:15:36

Can you tell me what happen and how to solve it.

Answer 1

You specify:

validates :approved, :presence => true

But in Rails:

false.present? # => false

Thus your validations are failing.

You can verify this by looking at the validation errors:

friendship = Friendship.create(:user_id=>6, :friend_id=>7, :approved=>0)
friendship.errors