Part 1, Chapter 5

After users log in, they should be taken to a dashboard that displays an overview of their user-related data. Even though we plan to use WebSockets for user-to-user communication, we still have a use for run-of-the-mill HTTP requests. Users should be able to query the server for information about their past, present, and future trips. Up-to-date information is vital to understanding where the user has travelled from or for planning where she is traveling next.

Our HTTP-related tests capture these scenarios.

All Trips

First, let's add a feature to let users view all of the trips associated with their accounts. As an initial step, we will allow users to see all existing trips; later on in this tutorial, we will add better filtering.


Add the following test case to the bottom of our existing tests in trips/tests/

# tests/

class HttpTripTest(APITestCase):

    def setUp(self):
        user = create_user()
        self.client = APIClient()
        self.client.login(username=user.username, password=PASSWORD)

    def test_user_can_list_trips(self):
        trips = [
            Trip.objects.create(pick_up_address='A', drop_off_address='B'),
            Trip.objects.create(pick_up_address='B', drop_off_address='C')
        response = self.client.get(reverse('trip:trip_list'))
        self.assertEqual(status.HTTP_200_OK, response.status_code)
        exp_trip_ids = [str( for trip in trips]
        act_trip_ids = [trip.get('id') for trip in]
        self.assertCountEqual(exp_trip_ids, act_trip_ids)

Update the imports as well:

# trips/tests/

from django.contrib.auth import get_user_model
from rest_framework import status
from rest_framework.reverse import reverse
from rest_framework.test import APIClient, APITestCase

from trips.serializers import TripSerializer, UserSerializer # new
from trips.models import Trip # new

Our test creates two trips and then makes a call to the trip list API, which should successfully return the trip data.

For now, the test should fail:

(env)$ python test trips.tests


ImportError: cannot import name 'TripSerializer'

We have a lot of work to do in order to get the test passing.


First, we need to create a model that represents the concept of a trip. Update the trips/ file as follows:

# trips/

import uuid # new

from django.db import models # new
from django.shortcuts import reverse # new
from django.contrib.auth.models import AbstractUser

class User(AbstractUser):

class Trip(models.Model): # new
    STATUSES = (

    id = models.UUIDField(primary_key=True, default=uuid.uuid4, editable=False)
    created = models.DateTimeField(auto_now_add=True)
    updated = models.DateTimeField(auto_now=True)
    pick_up_address = models.CharField(max_length=255)
    drop_off_address = models.CharField(max_length=255)
    status = models.CharField(
        max_length=20, choices=STATUSES, default=REQUESTED)

    def __str__(self):
        return f'{}'

    def get_absolute_url(self):
        return reverse('trip:trip_detail', kwargs={'trip_id':})

Since a trip is simply a transportation event between a starting location and a destination, we included a pick-up address and a drop-off address. At any given point in time, a trip can be in a specific state, so we added a status to identify whether a trip is requested, started, in progress, or completed. Lastly, we need to have a consistent way to identify and track trips that is also difficult for someone to guess. So, we use a UUID for our Trip model.

Let's make a migration for our new model and run it to create the corresponding table.

(env)$ python makemigrations
(env)$ python migrate


Now that our database has a Trip table, let's set up the corresponding admin page. Open trips/ and register a TripAdmin.

# trips/

from django.contrib import admin
from django.contrib.auth.admin import UserAdmin as DefaultUserAdmin

from .models import Trip, User # changed

class UserAdmin(DefaultUserAdmin):

# new
class TripAdmin(admin.ModelAdmin):
    fields = (
        'id', 'pick_up_address', 'drop_off_address', 'status', 'created', 'updated',
    list_display = (
        'id', 'pick_up_address', 'drop_off_address', 'status', 'created', 'updated',
    list_filter = (
    readonly_fields = (
        'id', 'created', 'updated',

Visit the admin page and add a new Trip record. You should see something like the following.

drf log in page


Like the user data, we need a way to serialize the trip data to pass it between the client and the server, so add a new serializer to the bottom of the trips/ file:

# trips/

class TripSerializer(serializers.ModelSerializer):
    class Meta:
        model = Trip
        fields = '__all__'
        read_only_fields = ('id', 'created', 'updated',)

Add at the top the import:

from .models import Trip

By identifying certain fields as "read only", we can ensure that they will never be created or updated via the serializer. In this case, we want the server to be responsible for creating the id, created, and updated fields.


Add the TripView to trips/

# trips/

class TripView(viewsets.ReadOnlyModelViewSet):
    permission_classes = (permissions.IsAuthenticated,)
    queryset = Trip.objects.all()
    serializer_class = TripSerializer

As you can see, our TripView is incredibly basic. We leveraged the DRF ReadOnlyModelViewSet to support our trip list and trip detail views. For now, our view will return all trips. Note that like the LogOutView, a user needs to be authenticated in order to access this API.

Update the imports like so:

# trips/

from django.contrib.auth import get_user_model, login, logout
from django.contrib.auth.forms import AuthenticationForm
from rest_framework import generics, permissions, status, views, viewsets # new
from rest_framework.response import Response

from .models import Trip # new
from .serializers import TripSerializer, UserSerializer # new


Include the trip-specific URL configuration in the main URLs file, taxi/

# taxi/

from django.contrib import admin
from django.urls import include, path # new

from trips.views import SignUpView, LogInView, LogOutView

urlpatterns = [
    path('api/sign_up/', SignUpView.as_view(), name='sign_up'),
    path('api/log_in/', LogInView.as_view(), name='log_in'),
    path('api/log_out/', LogOutView.as_view(), name='log_out'),
    path('api/trip/', include('trips.urls', 'trip',)), # new

Then, add our first trip-specific URL, which enables our TripView to provide a list of trips. Create a trips/ file and populate it as follows:

# trips/

from django.urls import path

from .views import TripView

app_name = 'taxi'

urlpatterns = [
    path('', TripView.as_view({'get': 'list'}), name='trip_list'),

If curious, you can read more about the need to set app_name here.

When we run our tests again, we get our list of trips:

(env)$ python test trips.tests

Single Trip

Our next, and last, HTTP test covers the trip detail feature. With this feature, users are able to retrieve the details of a trip identified by its primary key (UUID) value.

Add the following test to HttpTripTest in trips/tests/

# tests/

def test_user_can_retrieve_trip_by_id(self):
    trip = Trip.objects.create(pick_up_address='A', drop_off_address='B')
    response = self.client.get(trip.get_absolute_url())
    self.assertEqual(status.HTTP_200_OK, response.status_code)

Here, we leveraged the use of the handy get_absolute_url function on our Trip model to identify the location of our Trip resource. We added asserts that get the serialized data of a single trip and a success status.

Of course, we create a failing test to begin:

(env)$ python test trips.tests


django.urls.exceptions.NoReverseMatch: Reverse for 'trip_detail' not found.
'trip_detail' is not a valid view function or pattern name.

Update the Tripview in trips/, like so:

# trips/

class TripView(viewsets.ReadOnlyModelViewSet):
    lookup_field = 'id' # new
    lookup_url_kwarg = 'trip_id' # new
    permission_classes = (permissions.IsAuthenticated,)
    queryset = Trip.objects.all()
    serializer_class = TripSerializer

Supporting our new functionality is as easy as adding two variables to our TripView:

  1. The lookup_field variable tells the view to get the trip record by its id value.
  2. The lookup_url_kwarg variable tells the view what named parameter to use to extract the id value from the URL.

Add the URL to trips/

# trips/

from django.urls import path, re_path  # changed

from .views import TripView

app_name = 'taxi'

urlpatterns = [
    path('', TripView.as_view({'get': 'list'}), name='trip_list'),
    path('<uuid:trip_id>/', TripView.as_view({'get': 'retrieve'}), name='trip_detail'),  # new

We identified a trip_id in our URL configuration, which should be a UUID.

Ensure the tests pass:

(env)$ python test trips.tests

Mark as Completed