Django REST framework tutorial

https://www.django-rest-framework.org/tutorial/1-serialization/

Useful

Curl alternative

pip install httpie
http http://127.0.0.1:8000/snippets/

Progress

1. Initial setup

2. Created serializers.py - way to serialize/deserialize instances.

   1. serializers.Serializer - manually defining properties, later we can use ModelSerializer
   2. AFter we created model instance - we can serialize into bytes.

   serializer = SnippetSerializer(instance)
   content = JSONRenderer().render(serializer.data)

   3. And also deserialize it

   stream = io.BytesIO(content)
   data = JSONParser().parse(stream)
   serializer = SnippetSerializer(data=data)
   serializer.is_valid()
   serializer.validated_data # ordered dict
   serializer.save() # saves instance in the database

   4. This works with multiple instances too: serializer = SnippetSerializer(Snippet.objects.all(), many=True)

3. Moving to ModelSerializer - just like Form has ModelForm, Serializer has ModelSerializer = code is more concise

   1. We can print the actual code of model serializer: print(repr(SnippetSerializer()))

4. Writing regular Django views using our Serializer

5. Part 2 - Introduction to Request and Response classes. Response renders content based on requested content-type.

   1. Use constants for http status codes rather than numeric values!

6. Rewrite views to use mixins and Request response classes.

7. Add format_suffix_patterns

   1. this helps with specifying whether we want response in json or browsable api format (html)

8. Part 3

   1. Mixins replace most of the basic verbose functionality. See each views.py file

Part 4

• Code snippets are always associated with a creator.
• Only authenticated users may create snippets.
• Only the creator of a snippet may update or delete it.
• Unauthenticated requests should have full read-only access.

Associating Snippets with Users - override in SnippetListView:

 def perform_create(self, serializer):
    serializer.save(owner=self.request.user)

Also nice to notice - adding list of ids from snippets that user has created. These are the FK's in snippets table,

representing ID of user.

# User serializer
snippets = serializers.PrimaryKeyRelatedField(many=True, queryset=Snippet.objects.all())

Adding readonly key for snippet GET requests - the owner field

This field will be only used when GETting data, it will be omitted on PUT.

owner = serializers.ReadOnlyField(source='owner.username')

Alternative: CharField(read_only=True)

Permissions

• permission_classes = [permissions.IsAuthenticatedOrReadOnly] - will ensure that authenticated requests get read-write access, and unauthenticated requests get read-only access (still will display data).

Adding login to the Browsable API

urlpatterns += [
    path('api-auth/', include('rest_framework.urls')),
]