Rails 7 prevents use of reserved names as model attributes

Rails 7 prevents use of reserved names by raising an error while running migration. This is helpful to prevent mistakes like using names which are already available in rails as a part of instance methods from ActiveRecord. For Example: attributes, attribute_names, errors e.t.c

Before Rails 7.1

It was possible to use reserved names and rails won’t complaint until it is used in the code. Here is the example:

class CreateUsers < ActiveRecord::Migration[6.0]
  def change
    create_table :users do |t|
      t.string :name
      t.string :email
      t.jsonb :attributes, default: {}
      t.timestamps
    end
  end
end

Running this migration would just like any other migration without any issues. Its only when you try to use it in the code it raises the error.

User.create!(
  name: "SparkRails",
  email: "hello@sparkrails.com",
  attributes: { checked: true }
)

=> attributes is defined by Active Record. 
Check to make sure that you don't have an attribute 
or 
method with the same name. (ActiveRecord::DangerousAttributeError)

In Rails 7

Rails 7 raises an error that says “Could not generate field attributes as it is already defined by Active Record”. This is valid for any public and private methods that is already part of ActiveRecord. This will save your time by raising an error right before you add it to the table.

rails g migration create_users name:string email:string attributes:jsonb

=> Could not generate field 'attributes', as it is already defined by Active Record.

💡 Did You Know?

Rails 7 Introduces a new syntax for Enum