How to use postgresql stored_procedure on Django Rest_framework - django-rest-framework

I'm learning how to use django rest API for my project. I created a stored_procedure on my postgresql and I want to incorporate it to my project
I did make one but without serializers or any related to the rest API, just plain django
here's my views.py without the rest_framework
def add(request):
if request.method == "POST":
if request.POST.get('office_id') and request.POST.get('sem') and request.POST.get('sy') and request.POST.get('incident_details') and request.POST.get('resolution') and request.POST.get('studid'):
saverec = Clearanceinsert()
saverec.office_id = request.POST.get('office_id')
saverec.sem = request.POST.get('sem')
saverec.sy = request.POST.get('sy')
saverec.remarks = request.POST.get('incident_details')
saverec.resolution = request.POST.get('resolution')
saverec.studid = request.POST.get('studid')
cursor = connection.cursor()
email = request.user.userid
cursor.execute("select add_clearance_item('"+saverec.office_id+"','"+saverec.sem+"','"+saverec.sy+"','"+saverec.remarks+"','"+saverec.resolution+"','"+email+"','"+saverec.studid+"')")
return render(request, 'clearance/index.html')
else:
return render(request, 'clearance/add.html')
views.py using rest_framework
#api_view(['POST'])
def saveitem(request):
if request.method == 'POST':
saveserialize = Insertserialize(data=request.data)
if saveserialize.is_valid():
cursor = connection.cursor()
cursor.execute("select add_clearance_item('"+saveserialize.office_id+"','"+saveserialize.sem+"','"+saveserialize.sy+"','"+saveserialize.remarks+"','"+saveserialize.resolution+"','"+saveserialize.studid+"')")
return Response(saveserialize.data, status=status.HTTP_201_CREATED)
return Response(saveserialize.data, status=status.HTTP_400_BAD_REQUEST)
When using rest_framework code, It's throwing an error 'Insertserialize' object has no attribute 'office_id'
serializer.py
class Insertserialize(serializers.ModelSerializer):
class Meta:
model = ClearanceItem
fields = [
'office_id',
'sem',
'sy',
'remarks',
'resolution',
'studid'
]
hope someone can help me with this

Related

not a valid choice in django restframework serializer

i set my post model with choice and migrate model.
after that i create postserializer for create
and i run the server and post with data in postman for test,
but i got the 'is not a valid choice' err on serializer.
here is my model,
class Post(models.Model):
CATEGORY_CHOICES = (
('mc', 'MIRACLE'),
('hw', 'HOMEWORK')
)
title = models.CharField(max_length=50)
category = models.CharField(max_length=2, choices=CATEGORY_CHOICES)
content = models.TextField()
author = models.ForeignKey(settings.AUTH_USER_MODEL, on_delete=models.CASCADE)
serializer,
class PostCreateSerializer(serializers.ModelSerializer):
class Meta:
model = Post
fields = '__all__'
view
class PostAPI(APIView):
def post(self, request):
data = {
'title' :request.data['title'],
'category':request.data['category'],
'content' :request.data['content'],
'author' :request.user.id
}
serializer = PostCreateSerializer(data=data)
if serializer.is_valid():
serializer.save()
else:
print(serializer.erros)
...
and request data (in Postman)
{
'title':'test_title',
'category':'HOMEWORK',
'content':'test_content'
}
result is
{'category': [ErrorDetail(string='"HOMEWORK" is not a valid choice.', code='invalid_choice')]}
i tried request with changing category 'HOMEWORK' to 'hw'
then it works
but i want request with large one
Your error on serialize level. Try this
readable_to_choice = {"HOMEWORK": "hw", "MIRACLE": "mc"}
data = {'title' :request.data['title'],
'category': readable_to_choice.get(request.data['category']),
'content' :request.data['content'],
'author' :request.user.id}
serializer = PostCreateSerializer(data=data)
UPD: you should make your api func like this:
serializer = PostCreateSerializer(data=request.data)
serializer.is_valid(raise_exception=True)
print(serializer.data) # do logic with that data
and try to override to_internal_value method in your serializer. for example:
def to_internal_value(self, data):
readable_to_choice = {"HOMEWORK": "hw", "MIRACLE": "mc"}
data["category"] = readable_to_choice.get(data["category"])
res = super().to_internal_value(data)
return res
I think this way is more accurate

Retrieve Single Object in Modelviewset

I was using CBV, ModelViewSet but somehow my API Keep showing all the Objects inside, how i get my ModelViewSet retrieve a single object that base on my sku ?
api/views.py
class SamAPIViewSet(viewsets.ModelViewSet):
queryset = SamModels.objects.all()
serializer_class = SamSerializers
lookup_field = 'pk'
def get_queryset(self):
return self.queryset
def get_object(self):
sku_id = self.kwargs['pk']
return self.get_queryset().filter(id=sku_id)
def list(self, request):
products = SamModels.objects.all()
serializers = self.get_serializer(products, many=True)
return Response(serializers.data)
def retrieve(self, request, *args, **kwargs):
instance = self.get_object()
serializers = self.get_serializer(instance)
return Response(serializers.data)
api/urls.py
sam_api_list = SamAPIViewSet.as_view({
'get': 'list'
})
sam_api_detail = SamAPIViewSet.as_view({
'get': 'retrieve'
})
urlpatterns = [
url(r'sam', sam_api_list, name='api-sam'),
url(r'sam/<int:pk>', sam_api_detail, name='api-sam-detail'),
]
sam/1, it return all of my objects, i am not sure what wrong, my object has name, id, sku and how do i change my view to get retrieve single object base on my sku and not my id ?
Your routes are upside down. Try this:
urlpatterns = [
url(r'sam/<int:pk>', sam_api_detail, name='api-sam-detail'),
url(r'sam', sam_api_list, name='api-sam'),
]
Django will select the first expression that matches. If r'sam' is above r'sam/int:pk' then it will select r'sam' without going down to the next entry
url(r'sam/<int:pk>', sam_api_detail, name='api-sam-detail'),
url(r'sam', sam_api_list, name='api-sam'),
to
path(r'sam/<str:pk>', sam_api_detail, name='api-sam-detail'),
path(r'sam', sam_api_list, name='api-sam'),
remove
def get_queryset(self):
return self.queryset
def get_object(self):
sku_id = self.kwargs['pk']
return self.get_queryset().filter(id=sku_id)
and change lookup_field = 'pk' to lookup_field = 'sku'

How to return a queryset as a JSON response in Django RESTFramework?

I am trying to return a queryset as a JSON response in DRF but I always get a TypeError Object Not JSON serializable.
I have tried different methods but none of them worked. I have tried to use the JSONRenderer class and I have also tried to serialize a single object using SentSerializer. But nothing seems to solve the issue. I have just started learning DRF so it is a little confusing to me and really don't understand how serializers work and I am not sure if I have written them correctly or using them correctly.
# models
...
from django.contrib.auth.models import User
class Sentence(models.Model):
sent = models.CharField(max_length=255)
sent_correct = models.CharField(max_length=255, null=True)
pub_date = models.DateTimeField(default=timezone.now)
author = models.ForeignKey(User, on_delete=models.CASCADE, null=True, related_name='sentences')
# serializers
...
from django.contrib.auth.models import User
class UserSerializer(serializers.ModelSerializer):
password = serializers.CharField(write_only=True)
username = serializers.CharField(max_length=50)
class Meta:
model = User
# Tuple of serialized model fields (see link [2])
fields = ( "id", "username", "password", )
class SentSerializer(serializers.ModelSerializer):
sent = serializers.CharField(max_length=255)
sent_correct = serializers.CharField(max_length=255, required=False)
author = UserSerializer(read_only=True, required=False)
class Meta:
model = Sentence
fields = (
'sent', 'sent_correct', 'author'
)
# views
...
class SentCreateAPIView(APIView):
serializer_class = SentSerializer
permission_classes = (IsAuthenticated,)
def post(self, request):
ss = Sentence.objects.filter(author=request.user)[0:1]
ss = list(ss)
print("sentences " + str(ss))
serializer = self.serializer_class(data=request.data)
serializer.is_valid(raise_exception=True)
vd = serializer.validated_data
sent_str = vd['sent']
s = Sentence(sent=sent_str, sent_correct=sent_str)
s.author = request.user
print(vd)
print(request.user)
s.save()
sent = nlp(sent_str)
tokens = [t.text for t in sent] # this list returns successfully
return Response(
{ 'sent': sent_str,
'sent_correct': sent_str,
'tokens': tokens,
'ss': ss, # this list throws TypeError},
status=status.HTTP_201_CREATED
)
Jakub Maślanka answered my question on Facebook in Django Python Web Framework group. I had to serialize the queryset like this:
# views.py
...
return Response(
{ 'sent': sent_str,
'sent_correct': sent_str,
'tokens': tokens,
'ss': SentSerializer(ss, many=True).data},
status=status.HTTP_201_CREATED
)
ss -> dict
Why dont you use generics.ListAPIView.
It has get_query_set method
You just need to override that method by your own query set
Less code is better -> class based and framework

Django REST Framework - Extending ListAPIView with custom PUT method

I developed APIs using Django REST Framework for an inventory management application.
The endpoint to GET the list of products includes query parameters to filter the list. See below.
Product List View:
class ProductListAPIView(ListAPIView):
serializer_class = ProductListSerializer
queryset = Product.objects.all()
permission_classes = [DjangoModelPermissionsWithView]
filter_backends = [SearchFilter, DjangoFilterBackend, OrderingFilter]
search_fields = [
'sku',
'product_name',
...
]
filter_class = ProductFilter
pagination_class = ProductPageNumberPagination
ordering = ['-id']
ordering_fields = [
'id',
'sku',
'product_name',
...
]
def get_serializer_context(self, *args, **kwargs):
return {"request": self.request}
I have created another view to handle requests in order export the products to PDF, CSV, etc:
class ProductExportAPIView(APIView):
def put(self, request, *args, **kwargs):
# We use the seriaziler only to validate request.data
serializer = ProductExportSerializer(data=request.data)
if serializer.is_valid():
user_id = request.user.pk
file_key = request.data.get('file_key')
file_name = request.data.get('file_name', '')
extra_args = request.data.get('extra_args', {})
product_ids = request.data.get('product_ids')
# NOTE THAT export_file IS A CELERY TASK
export_file.delay(user_id, file_key, file_name, product_ids, extra_args)
return Response(status=status.HTTP_204_NO_CONTENT)
return Response(serializer.errors, status=status.HTTP_400_BAD_REQUEST)
The API it's working fine, but it works only if the user selects the products - the product_ids field is used to provide the list of products to be exported.
I would like to let the users export ALL the products via ProductExportAPIView by providing the query params that I'm using with ProductListAPIView rather than providing product_ids.
product_ids should be an optional field to be used only to export a few products.
How I can enable query parameters filtering on my ProductExportAPIView, there is a way to do this without hardcoding it? Can I extend ProductListAPIView with the PUT method to export products?
In order to use the same query parameters defined in ProductListAPIView, now ProductExportAPIView extends ProductListAPIView, so it inherits everything I needed:
class ProductExportAPIView(ProductListAPIView):
permission_classes = [AllowAny]
http_method_names = ['put'] # disable GET method inherited from ProductListAPIView
def put(self, request, *args, **kwargs):
queryset = self.filter_queryset(self.get_queryset())
# We use the serializer only to validate request.data
serializer = ProductExportSerializer(data=request.data)
if serializer.is_valid():
user_id = request.user.pk
file_key = request.data.get('file_key')
file_name = request.data.get('file_name', '')
extra_args = request.data.get('extra_args', {})
product_ids = request.data.get('product_ids', [])
if len(product_ids)==0:
product_ids = [p.pk for p in queryset]
export_file.delay(user_id, file_key, file_name, product_ids, extra_args)
return Response(status=status.HTTP_204_NO_CONTENT)
return Response(serializer.errors, status=status.HTTP_400_BAD_REQUEST)

Getting "AttributeError: 'QuerySet' object has no attribute '_meta'" on django rest "PUT" method

I am trying to update the record with PUT method, Getting AttributeError: 'QuerySet' object has no attribute '_meta'.
My models.py:
class TableInfo(models.Model):
table_name = models.CharField(max_length=10)
columns = JSONField(null=False)
serializer.py:
class TableInfoSerializer(serializers.ModelSerializer):
class Meta:
model = TableInfo
fields = '__all__'
views.py :
#api_view(['GET','PUT'])
def table_info(request):
try:
queryset = TableInfo.objects.all()
print("1")
except TableInfo.DoesNotExist:
return Response(status=status.HTTP_404_NOT_FOUND)
if request.method == 'GET':
print("2")
serializer_class = TableInfoSerializer(queryset, many=True)
return Response(serializer_class.data)
elif request.method == 'PUT':
print(request.data)
serializer = TableInfoSerializer(queryset, data=request.data)
if serializer.is_valid():
serializer.save()
print("4")
return HttpResponse(serializer.data)
return Response(serializer.errors, status=status.HTTP_400_BAD_REQUEST)
code is breaking at if serializer.is_valid():
On "GET" I am getting the result. Please help me with "PUT" method.
This error happens with PUT because the serializer tries to access the Meta class on the model instance it is updating, but fails because you are not passing a model instance - you're passing a queryset as indicated in the comments.
So you need to pass an instance, and to specify which instance you would normally pass the instance id via the URL. For that you would be best to separate out your views, and create a table_detail view for retrieving and updating a specific instance.
#api_view(['GET','PUT'])
def table_detail(request, pk):
try:
table_info = TableInfo.objects.get(pk=pk) # Lookup a specific object
except TableInfo.DoesNotExist:
return Response(status=status.HTTP_404_NOT_FOUND)
if request.method == 'GET':
serializer_class = TableInfoSerializer(table_info)
return Response(serializer_class.data)
elif request.method == 'PUT':
serializer = TableInfoSerializer(table_info, data=request.data)
if serializer.is_valid():
serializer.save()
return Response(serializer.data)
return Response(serializer.errors, status=status.HTTP_400_BAD_REQUEST)
Your table_info view can then just handle the list operation.
#api_view(['GET'])
def table_info(request):
if request.method == 'GET':
queryset = TableInfo.objects.all()
serializer_class = TableInfoSerializer(queryset, many=True)
return Response(serializer_class.data)

Resources