pycon.fr 2018 - Django REST framework workshop

1. Atelier Django REST framework pycon.fr 2018 Xavier Ordoquy Linovia
2. DRF Content negotiation / Parser Router Authentication / Permissions / Throttling Deserialization Processing / Pagination / Filtering Serialization Renderer Middleware
3. Négociation de contenu request content HTML form JSON YAML XML
4. Parsers / Renderers b'{"demo": 1}’ <class bytes> b'"2015-06-03"' <class bytes> {"demo": 1} <class dict> "2015-06-03" <class str> JSONParser Binary world Python land JSONRenderer
5. Identification Permissions Throttling • Identification: Qui êtes-vous ? • Permissions: Pouvez-vous le faire ? • Throttling: Abusez-vous des ressources ?
6. (dé)sérialisation • Types de base Python <-> objets complexes • Etape de représentation • "2015-06-03" <-> datetime.date(2015, 6, 3) • Validation des entrées: • Vérification de typage • Sécurisation (injections diverses)
7. Serializers {"demo": 1} <class dict> "2015-06-03" <class str> <SomeObj> <class SomeObj> 2015-06-03 <class date> Serializer Unsafe Safe
8. Installation $ pip install djangorestframework django-cors-headers $ pip install httpie
9. settings.py INSTALLED_APPS = [ … 'rest_framework', 'teaching', 'corsheaders', ] … MIDDLEWARE = [ … 'corsheaders.middleware.CorsMiddleware', ] … CORS_ORIGIN_ALLOW_ALL = True
10. #1: API de base
11. teaching/serializers.py from rest_framework import serializers from . import models class CourseMaterialSerializer(serializers.ModelSerializer): class Meta: model = models.CourseMaterial fields = ['title', 'description', 'url', 'author']
12. teaching/api_views.py from rest_framework import viewsets from . import serializers, models class CourseMaterialViewSet(viewsets.ModelViewSet): queryset = models.CourseMaterial.objects.all() serializer_class = serializers.CourseMaterialSerializer
13. teaching/urls.py from rest_framework import routers from . import views, api_views router = routers.DefaultRouter() router.register( r'course_material', api_views.CourseMaterialViewSet, ) urlpatterns = [ … ] + router.urls
14. http://localhost/teaching/
15. Navigation • Page de garde: ➡ http://localhost:8000/teaching/ • Liste / creation: ➡ http://localhost:8000/teaching/course_material/ • Voir / mettre à jour / supprimer: ➡ http://localhost:8000/teaching/course_material/1/ • En JSon: ➡ …/teaching/course_material/?format=json ➡ …/teaching/course_material.json
16. Création http --json POST http://127.0.0.1:8000/teaching/course_material/\ author=1 description="blabla" title="bla" HTTP/1.1 201 Created Allow: GET, POST, HEAD, OPTIONS Content-Length: 60 Content-Type: application/json Date: Fri, 05 Oct 2018 23:05:39 GMT Location: None Server: WSGIServer/0.2 CPython/3.6.6 Vary: Accept, Cookie X-Frame-Options: SAMEORIGIN { "author": 1, "description": "blabla", "title": "bla", "url": null }
17. #2: test time
18. teaching/tests.py class TestTask(APITestCase): def test_task_creation(self): author = models.Author.objects.create( name="hodor", email="hodor@hodor.hodor", ) course_material = models.CourseMaterial.objects.create( title="Hodoooor", author=author, ) data = { 'title': "Hodoooor", 'description': None, 'author': 1, 'url': None, } url = reverse('teaching:coursematerial-list') response = self.client.post(url, data, format='json') self.assertEqual( response.status_code, status.HTTP_201_CREATED, response.content) self.assertEqual(response.data, data)
19. teaching/tests.py class TestTask(APITestCase): def test_task_creation(self): author = models.Author.objects.create( name="hodor", email="hodor@hodor.hodor", ) course_material = models.CourseMaterial.objects.create( title="Hodoooor", author=author, ) data = { 'title': "Hodoooor", 'description': None, 'author': 1, 'url': None, } url = reverse('teaching:coursematerial-list') response = self.client.post(url, data, format='json') self.assertEqual( response.status_code, status.HTTP_201_CREATED, response.content) self.assertEqual(response.data, data)
20. teaching/tests.py class TestTask(APITestCase): def test_task_creation(self): author = models.Author.objects.create( name="hodor", email="hodor@hodor.hodor", ) course_material = models.CourseMaterial.objects.create( title="Hodoooor", author=author, ) data = { 'title': "Hodoooor", 'description': None, 'author': 1, 'url': None, } url = reverse('teaching:coursematerial-list') response = self.client.post(url, data, format='json') self.assertEqual( response.status_code, status.HTTP_201_CREATED, response.content) self.assertEqual(response.data, data)
21. teaching/tests.py class TestTask(APITestCase): def test_task_creation(self): author = models.Author.objects.create( name="hodor", email="hodor@hodor.hodor", ) course_material = models.CourseMaterial.objects.create( title="Hodoooor", author=author, ) data = { 'title': "Hodoooor", 'description': None, 'author': 1, 'url': None, } url = reverse('teaching:coursematerial-list') response = self.client.post(url, data, format='json') self.assertEqual( response.status_code, status.HTTP_201_CREATED, response.content) self.assertEqual(response.data, data)
22. teaching/tests.py class TestTask(APITestCase): def test_task_creation(self): author = models.Author.objects.create( name="hodor", email="hodor@hodor.hodor", ) course_material = models.CourseMaterial.objects.create( title="Hodoooor", author=author, ) data = { 'title': "Hodoooor", 'description': None, 'author': 1, 'url': None, } url = reverse('teaching:coursematerial-list') response = self.client.post(url, data, format='json') self.assertEqual( response.status_code, status.HTTP_201_CREATED, response.content) self.assertEqual(response.data, data)
23. teaching/tests.py class TestTask(APITestCase): def test_task_creation(self): author = models.Author.objects.create( name="hodor", email="hodor@hodor.hodor", ) course_material = models.CourseMaterial.objects.create( title="Hodoooor", author=author, ) data = { 'title': "Hodoooor", 'description': None, 'author': 1, 'url': None, } url = reverse('teaching:coursematerial-list') response = self.client.post(url, data, format='json') self.assertEqual( response.status_code, status.HTTP_201_CREATED, response.content) self.assertEqual(response.data, data)
24. Lancer le test (tp-atelier-django)[monprojet]$ python manage.py test Creating test database for alias 'default'... System check identified no issues (0 silenced). . ---------------------------------------------------------------- Ran 1 test in 0.015s OK Destroying test database for alias 'default'... (tp-atelier-django)[monprojet]$
25. teaching/tests.py from django.urls import reverse from rest_framework import status from rest_framework.test import APITestCase from . import models
26. teaching/tests.py class TestTask(APITestCase): def test_task_creation(self): data = { 'title': "Hodoooor", 'description': None, 'author': 1, 'url': None, } author = models.Author.objects.create( name="hodor", email="hodor@hodor.hodor", ) course_material = models.CourseMaterial.objects.create( title="Hodoooor", author=author, ) url = reverse('teaching:coursematerial-list') response = self.client.post(url, data, format='json') self.assertEqual( response.status_code, status.HTTP_201_CREATED, response.content) self.assertEqual(response.data, data)
27. Lancer le test (tp-atelier-django)[monprojet]$ python manage.py test Creating test database for alias 'default'... System check identified no issues (0 silenced). . ---------------------------------------------------------------- Ran 1 test in 0.015s OK Destroying test database for alias 'default'... (tp-atelier-django)[monprojet]$
28. #4: Amélioration de la représentation
29. Author illisible http --json POST http://127.0.0.1:8000/teaching/course_material/\ author=1 description="blabla" title="bla" HTTP/1.1 201 Created Allow: GET, POST, HEAD, OPTIONS Content-Length: 60 Content-Type: application/json Date: Fri, 05 Oct 2018 23:05:39 GMT Location: None Server: WSGIServer/0.2 CPython/3.6.6 Vary: Accept, Cookie X-Frame-Options: SAMEORIGIN { "author": 1, "description": "blabla", "title": "bla", "url": null }
30. teaching/serializers.py class CourseMaterialSerializer(serializers.ModelSerializer): author = serializers.SlugRelatedField( slug_field='name', queryset=models.Author.objects.all(), ) class Meta: model = models.CourseMaterial fields = ['title', 'description', 'url', 'author']
31. Author amélioré http --json POST http://127.0.0.1:8000/teaching/course_material/\ author=1 description="blabla" title="bla" HTTP/1.1 201 Created Allow: GET, POST, HEAD, OPTIONS Content-Length: 60 Content-Type: application/json Date: Fri, 05 Oct 2018 23:05:39 GMT Location: None Server: WSGIServer/0.2 CPython/3.6.6 Vary: Accept, Cookie X-Frame-Options: SAMEORIGIN { "author": "A. Christie", "description": "blabla", "title": "bla", "url": null }
32. Tests (tp-atelier-django)[monprojet]$ python manage.py test Creating test database for alias 'default'... System check identified no issues (0 silenced). F ================================================================= FAIL: test_task_creation (teaching.tests.TestTask) ----------------------------------------------------------------- Traceback (most recent call last): File "/Users/xordoquy/Documents/Devs/tp-atelier-django/monprojet/ teaching/tests.py", line 26, in test_task_creation response.content) AssertionError: 400 != 201 : b'{"author":["L\'object avec name=1 n\'existe pas."]}' ----------------------------------------------------------------- Ran 1 test in 0.016s FAILED (failures=1) Destroying test database for alias 'default'... (tp-atelier-django)[monprojet]$
33. teaching/tests.py class TestTask(APITestCase): def test_task_creation(self): author = models.Author.objects.create( name="hodor", email="hodor@hodor.hodor", ) course_material = models.CourseMaterial.objects.create( title="Hodoooor", author=author, ) data = { 'title': course_material.title, 'description': None, 'author': author.name, 'url': None, } url = reverse('teaching:coursematerial-list') response = self.client.post(url, data, format='json') self.assertEqual( response.status_code, status.HTTP_201_CREATED, response.content) self.assertEqual(response.data, data)
34. #5: Hyperliens
35. teaching/serializers.py from rest_framework import serializers from . import models class CourseMaterialSerializer(serializers.ModelSerializer): self_url = serializers.HyperlinkedIdentityField( 'coursematerial-detail', source='id', read_only=True) class Meta: model = models.CourseMaterial fields = [ 'title', 'description', 'url', 'author', 'self_url', ]
36. #5: Représentations imbriquées
37. Exemple { "author": { "email": "a@a.fr", "id": 3, "name": "aha" }, "description": "Description", "title": "titre !", "url": null }
38. serializers.py class AuthorSerializer(serializers.ModelSerializer): id = serializers.IntegerField(required=False) class Meta: model = models.Author fields = ['id', 'name', 'email'] class CourseMaterialSerializer(serializers.ModelSerializer): author = AuthorSerializer(read_only=True) class Meta: model = models.CourseMaterial fields = ['title', 'description', 'url', 'author']
39. Résultat http --json http://127.0.0.1:8000/teaching/course_material/1/ -s colorful HTTP/1.1 200 OK … { "author": { "email": "unknown@example.com", "id": 1, "name": "A. Christie" }, "description": "Le crime de l'Orient-Express", "title": "Résoudre un mystère", "url": null }
40. #5: Représentations imbriquées modifiables
41. serializers.py class AuthorSerializer(serializers.ModelSerializer): id = serializers.IntegerField(required=False) class Meta: model = models.Author fields = ['id', 'name', ‘email'] class CourseMaterialSerializer(serializers.ModelSerializer): author = AuthorSerializer(read_only=True) class Meta: model = models.CourseMaterial fields = ['title', 'description', 'url', 'author']
42. serializers.py class CourseMaterialSerializer(serializers.ModelSerializer): … def create(self, validated_data): author = self.create_or_update_author( validated_data.pop('author') ) course_material = models.CourseMaterial.objects.create( author=author, **validated_data, ) return course_material
43. serializers.py class CourseMaterialSerializer(serializers.ModelSerializer): … def update(self, instance, validated_data): author = self.create_or_update_author( validated_data.pop('author') ) instance.title = validated_data['title'] instance.description = validated_data['description'] instance.email = validated_data['email'] instance.author = author instance.save() return instance
44. serializers.py class CourseMaterialSerializer(serializers.ModelSerializer): … def create_or_update_author(self, author_data): try: author = models.Author.objects.get( id=author_data.get('id'), ) author.name = author_data['name'] author.email = author_data['email'] except models.Author.DoesNotExist: author = models.Author(**author_data) author.save() return author
45. Résultat: http --json POST http://127.0.0.1:8000/teaching/course_material/\ author:='{"email": "a@a.fr", "name": "aha"}' \ description="blabla2" title="bla2" HTTP/1.1 201 Created … { "author": { "email": "a@a.fr", "id": 3, "name": "aha" }, "description": "blabla2", "title": "bla2", "url": null }
46. #6: actions
47. teaching/api_views.py from rest_framework import viewsets from rest_framework.decorators import action from rest_framework.response import Response from . import serializers, models class CourseMaterialViewSet(viewsets.ModelViewSet): queryset = models.CourseMaterial.objects.all() serializer_class = serializers.CourseMaterialSerializer @action(methods=['get'], detail=False) def authors(self, request, *args, **kwargs): authors = models.Author.objects.all() serializer = serializers.AuthorSerializer( instance=authors, many=True, ) return Response(serializer.data)
48. Résultat http --json http://127.0.0.1:8000/teaching/course_material/authors/ HTTP/1.1 200 OK Allow: GET, HEAD, OPTIONS Content-Length: 139 Content-Type: application/json Date: Sat, 06 Oct 2018 00:47:21 GMT Server: WSGIServer/0.2 CPython/3.6.6 Vary: Accept, Cookie X-Frame-Options: SAMEORIGIN [ { "email": "unknown@example.com", "id": 1, "name": "A. Christie" } ]