Django Rest Framework Many To Many Serialization Example

Django Rest Framework'te Many To Many Serializtaion

• models.py

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from django.db import models
​
class Tag(models.Model):
    name = models.CharField(max_length=20)
​
​
class Post(models.Model):
    title = models.CharField(max_length=120)
    tags = models.ManyToManyField(Tag, related_name="post")

• serializers.py

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from rest_framework import serializers
# internal
from my.models import Post, Tag
​
class TagSerializer(serializers.ModelSerializer):
    class Meta:
        model = Tag
        fields = '__all__'
​
​
class PostSerializer(serializers.ModelSerializer):
    tags = serializers.PrimaryKeyRelatedField(many=True,
                                              queryset=Tag.objects.all())
​
    class Meta:
        model = Post
        fields = ('id', 'title', 'tags')

• views.py

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class Posts(APIView):
    def get(self, request, format=None):
        posts = Post.objects.all()
        serializer = PostSerializer(posts, many=True)
        return Response(serializer.data)
​
    def post(self, request, format=None):
        serializer = PostSerializer(data=request.data)
        if serializer.is_valid():
            serializer.save()
            return Response(serializer.data, status=status.HTTP_201_CREATED)
        return Response(serializer.errors, status=status.HTTP_400_BAD_REQUEST)
​
class PostDetail(APIView):
    def get(self, request, pk, format=None):
        post = Post.objects.get(pk=pk)
        serializer = PostSerializer(post)
        return Response(serializer.data)
​
    def put(self, request, pk, format=None):
        post = Post.objects.get(pk=pk)
        serializer = PostSerializer(post, data=request.data)
        if serializer.is_valid():
            serializer.save()
            return Response(serializer.data)
        return Response(serializer.errors, status=status.HTTP_400_BAD_REQUEST)

• urls.py

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from django.urls import path
​
# internal
from my.views import Posts, PostDetail
​
urlpatterns = [  
    path('posts', Posts.as_view()),
    path('posts/<int:pk>', PostDetail.as_view()),
]

• URL http://127.0.0.1:8000/my/posts
• POST request data

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{
    "title":"Strong and Big Programming",
    "tags" : [2,4]  
}

• Kaydedilen data

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{
    "id": 28,
    "title": "Strong and Big Programming",
    "tags": [
        2,
        4
    ]
}

---

• GET request http://127.0.0.1:8000/my/customers

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HTTP 200 OK
Allow: GET, POST, HEAD, OPTIONS
Content-Type: application/json
Vary: Accept
​
[
    {
        "id": 27,
        "title": "Fast and Simple Programming",
        "tags": [
            1,
            4
        ]
    },
    {
        "id": 28,
        "title": "Strong and Big Programming",
        "tags": [
            2,
            4
        ]
    }
]

---

• PUT request http://127.0.0.1:8000/my/posts/27

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{
    
    "id" : 27,
    "title": "Fast and Very Simple Programming",
    "tags" : [1,4]
}

• UPDATED (Güncellenmiş) data:

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{
    "id": 27,
    "title": "Fast and Very Simple Programming",
    "tags": [
        1,
        4
    ]
}

Another way (Diğer Yöntem)

• serializers.py

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class PostSerializer2(serializers.ModelSerializer):
​
    class Meta:
        model = Post
        fields = ('id', 'title', 'tags')
​
    def create(self, validated_data):
        tags = validated_data.pop('tags')
        post = Post.objects.create(**validated_data)
        for tag in tags:
            post.tags.add(tag)
        return post

• PostSerializer2'yi views.py 'da kullanırsanız aynı sonucu alacaksınız.
• POST request yapalım yine http://127.0.0.1:8000/my/posts

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{
    "title":"Best Languages and Frameworks",
    "tags" : [ 4,3,2,1  ]
    
}

• Yine ID'leri dizi olarak verdik.
• Kaydedilen veri

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{
    "id": 32,
    "title": "Best Languages and Frameworks",
    "tags": [
        1,
        2,
        3,
        4
    ]
}

• PUT request http://127.0.0.1:8000/my/posts/32
• data:

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{
    "title":"Best languages and frameworks updated",
    "tags" : [ 2,1  ]
    
}
​

• Güncellenmiş (updated) data

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{
    "id": 33,
    "title": "Best languages and frameworks updated",
    "tags": [
        1,
        2
    ]
}
​