Alter existing model with a Redmine plugin

Question

The Redmine plugin tutorials explain how to wrap core models but what I need is to add another column to the journals table. I need a boolean field inserted in the journals model. Creating another model with a 'belongs_to :journal' relation seems like an overkill. Can this be done with a plugin? I should note that I am a rails newbie.

Answer 1

You just have to create the appropriate migration.

In your plugin's directory, create the file db/migrate/update_journal.rb with the following :

class UpdateJournal < ActiveRecord::Migration
    def self.up
        change_table :journal do |t|
            t.column :my_bool, :boolean
        end
    end

    def self.down
        change_table :journal do |t|
            t.remove :my_bool
        end
    end
end

Then you can execute the task rake db:migrate_plugins RAILS_ENV=production to update your database with the new field.

After executing the migration, your journal database will have the my_bool field that you'll be able to call like every other field.

Answer 2

I was able to extend the existing user model using the following code:

class UpdateUsers < ActiveRecord::Migration
  def up
    add_column :users, :your_new_column, :string, :default => ''
    add_column :users, :your_other_new_column, :string, :default => ''
  end

  def down
    remove_column :users, :your_new_column
    remove_column :users, :your_other_new_column
  end
end

Also I needed to name the migration file in way that it began with a number eg. myplugin/db/migrate/001_update_user.rb