11. CRUD using Viewsets

According to Django Documentation:

Django REST framework allows you to combine the logic for a set of related views in a single class, called a ViewSet. In other frameworks, you may also find conceptually similar implementations named 'Resources' or 'Controllers'.

A ViewSet class is simply a type of class-based View, that does not provide any method handlers such as .get() or .post(), and instead provides actions such as .list() and .create().

The method handlers for a ViewSet are only bound to the corresponding actions at the point of finalizing the view, using the .as_view() method.

1. We use viewsets.ViewSet class for list(), retrieve(), update(), create, delete(). The viewsets.ModelViewSet uses only queryset and serializer_class and provides for pk and non-pk-based operations.

2. To use Viewsets, we use ROUTERS with the paths that we normally use in our Django project.  So we comment on the paths we used with function-based, class-based, mixins, and generics in our URLS.PY.

3.  Update the VIEWS.PY as:

We further update our URLS.PY to include the basename as the name of our model.

So, when we run our path for Employees:

4.  For other CRUD operations, we create a new method, CREATE, to add a new record:

This results to:

5.  To retrieve a single record,  we don't have to create a separate path for our employee details, by using the retrieve method, we can get this record immediately.

Our URLS.PY is still this:

6. To delete a record, we create a new method:

 

7. To update the record, 

8. Our updated Employee model shall look like this:

Using the steps above, we were able to create one class with several methods to perform CRUD operations. However, there is an easier alternative, the use of viewsets.ModelViewset, which will handle all the CRUD operations an easier and more efficient way.

To add a new record:

To update a record:

To delete a record:

Viewing our updated list:

To view a non-existent record, it also shows validations:

9. In summary, the viewsets.ModelViewset is much faster than other methods.

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