This extension keeps track of your models giving them unique ids so you can easily use them in junction tables. In the future I plan to improve this extension so it will be something like ContentTypes from Django framework.
Add yii2-contenttypes to the require section of your composer.json file:
{
"require": {
"stepanorda/yii2-contenttypes": "*"
}
}
Then run the command:
$ php composer.phar update
Apply the migration:
$ php yii migrate/up --migrationPath=@vendor/stepanorda/yii2-contenttypes/migrations
Apache License 2.0 http://www.apache.org/licenses/