Now that you're already familiar with the class-based views, this video will walk you through the steps to create a fully functional crude APA project that can allow you to read from the database, display records, update, and delete them with just a few lines of code. You already know how to create a Django project and install TRF with a virtual environment using P band. Let's do that. Create a new app called little lemon API and include this app in the setting.py file. Ensure you have included the rest Framework app as well. Otherwise, TRF will not work. You need a database model first. Let's open the models.py file and add three fields, title, price, and inventory. Now make the migrations and migrate them. Another thing you need for this project, is a serializers object. By now, you know that serializers helped to convert model instances into Python datatypes that can be displayed as JSON or XML. It also helps you to convert HTTP request body into Python datatypes and made them to a model instance. But you'll learn more about these three different types of serializers later. For now, let's just create a simple model serializer. Open a new file inside the little lemon API app called serializers.py and add the following code. Don't worry about the details right now. But make sure that it has every field from the main whiter model in the field section. Now, open the little lemon api/view.py file. This is where you will write code for this project. This time, you're not going to write everything from scratch. Instead, you'll take advantage of the generate view classes built into TRF. These classes have everything built into them for crude operations. Import the generics module from the Django rest framework, the menu item model, and the serializer, you just created. Menu item, serializer. Now it's time for some direct magic. Create a new menu items view class and extend the ListCreateView class from the generics module. ListCreateView can display records and accept Post calls to create new records. To function correctly, at least CreateView needs two items, a queryset that retrieves all the records using a model, and a serializer class to display and store the records properly. Let's create those two items. You are almost done. It's time to map this class in the URL patterns. Create a new file called urls.py inside little lemon API app and add the URL pattern that you learned earlier. Views.MenuItemView.as_view. Next, include this file in the main urls.py file of your project. Just add the following line. Insert the URL patterns section. Path and then in parentheses, type api/include, add another set of parentheses and type LittleLemonAPI.urls and close the two sets of parenthesis. That's it. It's time to test your code. Run the web server using Pythonmanage.py, run server, and visit the local host url/api/menu items. At this point, you don't have any menu items, so none are included in the output. It's time to create records. Since you have extended listcreateapiview, this menu items endpoint automatically supports HTTP post calls. Scroll down and you'll notice a form to add menu items with the title, price and inventory fills. Great. Let's add some data and hit the Post button. Now, visit the menu items endpoint, and this time all your records are returned by this API. Next, let's display a single record using the endpoint menu items/itemid. For this, you need to create another class in your views.py file. Open the views.py file and create a new class called SingleMenuItemView. This time, we'll extend generics.RetrieveUpdate APIView, generics.DestroyApiView classes. RetrieveUpdateView class has everything to fetch a record, display it, and accept post calls to update them and DestroyApiView, has everything to accept, delete calls, and finally, delete a record. Just like before, you need a queryset and a serializer. You can copy those two lines from the MenuItemView class and paste them here. Met this new class in the little lemon api/urls.py file. You are done. Now, you can visit the localhost url/api/MenuItems/1 to display a single record. If you scroll down, you can see a form that you can use to update this record. There is also a Delete button, to delete the record. You can send HTTP, get, put, patch, and delete calls to this endpoint, which works without any issues. That's it. You have created a fully functional crude APA project using TRF with just a few lines of code. Congratulations. You also learned to take advantage of the generic view classes from the Django rest framework to avoid writing everything from scratch.
