yii2/docs/guide/gii.md

The Gii code generation tool

Yii2 includes a handy tool that allows rapid prototyping by generating commonly used code snippets as well as complete CRUD controllers.

Installing and configuring

Add these lines to your config file:

'modules' => [
	'gii' => ['yii\gii\Module']
]

How to use it

Creating your own templates

TDB