Build a Backend REST API with Python & Django - Advanced

Test your Travis-CI knowledge

Write a very simple unit test to demonstrate the process of unit testing code using Django.

Test your knowledge on Django Unit Tests

Use the Django management script to create a new app within our project. The app will be called 'core' and it will be used to hold all code that is central to our project (such as database models and the admin page).

Here we will create a custom user model for our project. The custom user model will replace Django's built in user model. The purpose of customising the model is to support handling registration and authentication using an email instead of username.

Implement the user model to make the tests pass.

Next we will implement a change to our custom user manager that ensures emails are normalized. Normalizing the email means ensuring the domain part is all lowercase.

Here we will add an extra validation step to our create_user function, so it will raise a validation error if a blank or null email field is passed in. We do this so a correct error message is displayed when using this function.

Now we will add support for creating superusers using the create_superuser function on our custom user manager. The create_superuser function is used by the Django createsuperuser management command, so it's required for creating admin using the CLI, which we will be doing later in the course.

Test your knowledge on the Django custom user model

Now we need to configure our Django admin to work with our custom user model. To do this, we need to make some modifications to the fields that Django displays in the default Django admin. In this video we setup the tests to test that our Django admin is working correctly.

Now we will modify the Django admin to support listing users from our custom user model. This should make the tests from the previous video pass successfully.

Here we modify the Django admin to support changing the custom user model. We start by adding a test to ensure the 'user change page' loads successfully, then we implement the feature by modifying the fieldsets of the default Django UserAdmin class.

Finally we can modify our Django admin to support creating new users. We start by testing the create user page, and end by making the necessary modifications to the add_fieldsets variable in our UserAdmin class.

Here we will prepare our docker-compose.yml for running PostgreSQL Database 10 as our application database. In this video we start the setup by setting some environment variables for authentication with the database, and also adding our db service.

Before our docker container will support connecting to PostgreSQL, we need to make a few minor modifications. First we will add the psycopg2 package to our requirements.txt file, then we will update our Dockerfile to support installing and using the client for our application.

Now we can configure our database within the Django settings.py file. We will do this by updating the DATABASES settings and pulling in some environment variables.

A common issue when using PostgreSQL with Django is that the application starts before the database. This causes it to fail with an OperationalError saying that the database is unavailable. To get around this, we will create a management command which we can use to delay starting our app until the database is up. We start by adding unit tests for our command. The unit tests will ensure the command works as expected when the database is and is not available.

Now we have our tests failing, we can go ahead and make them pass by creating our wait_for_db command.

Finally we can update our docker-compose.yml file to run our wait_for_db management command before starting our app. While we are doing that, we will also add migrate to run our migrations when we start our docker container.

Finally we can update our docker-compose.yml file to run our wait_for_db management command before starting our app. While we are doing that, we will also add migrate to run our migrations when we start our docker container.

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