I am sure that you are looking forward to applying some of the knowledge gained from the previous chapters and doing something practical and fun. As promised, in this chapter, we will do just that. Also, apart from implementing our own entity types, we will cover some new things as well. So, here's the game plan.

The premise is that we want to have products on our site that hold some basic product information, such as an ID, a name, and a product number. However, these products need to somehow get onto our site. One way will be manual entry. Another, more important way will be through an import from multiple external sources (such as a JSON endpoint). Now, things will be kept simple. For all intents and purposes, these products aren't going to do much, so don't expect an e-commerce solution being laid out for you. Instead, we will practice modeling data and functionality in Drupal 8.

First, we will create a simple content entity type to represent our products. In doing so, we will make sure that we can use the UI to create, edit, and delete these products with ease by taking advantage of many Entity API benefits available out of the box.

Second, we will model our importing functionality. One side of the coin will be a simple configuration entity type to represent the configuration needed for our various importers. Again, we will make use of the Entity API for quick scaffolding and entity management. The other side will be a custom plugin type that will actually perform the import based on the configuration found in the entities. As such, these will be linked from the direction of the config entities, which will choose to use one plugin or another.

So these are the highlights. In building all this, we will see much of what is needed to define a content and configuration entity type with fields to hold data and configuration, as well as a plugin type to encapsulate logic. When defining these things, we will take the manual, more tedious, route to make sure that we understand what each component does and we are comfortable with what we are doing. Once you know all that, you'll be able to greatly speed up these processes using the Drupal Console to automatically generate much of the boilerplate code.

The code we write in this chapter will go inside a new module called products. Since we have learned how to create a module from scratch, I will not cover the initial steps needed for getting started with it.