Saya pikir itu bukan rahasia bagi siapa pun yang dalam percakapan dengan pengembang Python yang berpengalaman, dan tidak hanya, frase sering tergelincir bahwa Django jahat, bahwa Django memiliki arsitektur yang buruk dan tidak mungkin untuk menulis proyek besar di atasnya tanpa rasa sakit. Bahkan proyek medium Django seringkali sulit untuk dipertahankan dan diperluas. Saya mengusulkan untuk mencari tahu mengapa ini terjadi dan apa yang salah dengan proyek Django.
Sedikit teori
Ketika kami mulai mempelajari Django tanpa pengalaman dari bahasa dan kerangka kerja lain, selain dokumentasi, kami membaca tutorial, artikel, buku, dan hampir semuanya kami melihat sesuatu seperti ini:
Django adalah kerangka kerja yang menggunakan pola desain Model-View-Controller (MVC).
Dan kemudian sekelompok diagram dan penjelasan yang tidak akurat tentang apa itu MVC. Mengapa mereka tidak akurat dan apa yang salah dengan mereka, Anda bisa lihat di sini atau di sini .
Biasanya, skema seperti itu menggambarkan MVC dengan cara ini:
Model - akses ke penyimpanan data
View adalah antarmuka yang digunakan pengguna untuk berinteraksi
Kontroler adalah sejenis objek penghubung antara model dan tampilan.
Skema umum ini hanya membingungkan dan menghalangi saat Anda ingin menulis aplikasi yang berisi logika bisnis.
Ada dua hal yang perlu diperhatikan.
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class CommentSerializer(serializers.Serializer):
email = serializers.EmailField()
content = serializers.CharField(max_length=200)
created = serializers.DateTimeField()
def create(self, validated_data):
return Comment.objects.create(**validated_data)
def update(self, instance, validated_data):
instance.email = validated_data.get('email', instance.email)
instance.content = validated_data.get('content', instance.content)
instance.created = validated_data.get('created', instance.created)
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class OrderSerializer(serializers.ModelSerializer):
class Meta:
model = Order
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# views.py
class OrderViewsSet(viewsets.ModelViewSet):
queryset = Order.objects.all()
serializer_class = OrderSerializer
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# views.py
class OrderCreateApi(views.APIView):
class InputSerializer(serializers.ModelSerializer):
number = serializers.IntegerField()
...
def post(self, request):
serializer = self.InputSerializer(data=request.data)
serializer.is_valid(raise_exception=True)
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order = Order.objects.create(**serializer.validated_data)
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# views.py
class OrderViewsSet(viewsets.ModelViewSet):
queryset = Order.objects.all()
serializer_class = OrderSerializer
def get_queryset(self):
queryset = super(OrderViewsSet, self).get_queryset()
queryset = queryset.filter(user=self.request.user)
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created = models.DateTimeField(auto_now_add=True)
status = models.CharField(max_length=16)
def update_status(self, status: str) -> None:
self.status = status
self.save(update_fields=('status',))
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class OrderCreateApi(views.APIView):
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number = serializers.IntegerField()
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serializer = self.InputSerializer(data=request.data)
serializer.is_valid(raise_exception=True)
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# views.py
class OrderListApi(views.APIView):
class OutputSerializer(serializers.ModelSerializer):
class Meta:
model = Order
fields = ‘__all__’
def get(self, request):
orders = Order.objects.filter(user=request.user)
#
# , Order.objects.filter(user=request.user, is_deleted=False, is_archived=False...)
# Manager
data = self.OutputSerializer(orders, many=True).data
return Response(data)
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class Order(models.Model):
number = serializers.IntegerField()
created = models.DateTimeField(auto_now_add=True)
status = models.CharField(max_length=16)
def update_status(self, status: str) -> None:
self.status = status
self.save(update_fields=('status',))
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# DTO
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# views.py
class OrderCreateApi(views.APIView):
class InputSerializer(serializers.ModelSerializer):
number = serializers.IntegerField()
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def post(self, request):
serializer = self.InputSerializer(data=request.data)
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# services.py
def order_get_by_user(user: User) -> Iterable[Order]:
return Order.objects.filter(user=user)
# views.py
class OrderListApi(views.APIView):
class OutputSerializer(serializers.ModelSerializer):
class Meta:
model = Order
fields = ('id', 'number', ...)
def get(self, request):
orders = services.order_get_by_user(user=request.user)
data = self.OutputSerializer(orders, many=True).data
return Response(data)
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