im trying to post the recruitment date of an employee , but i keep having the 400 bad request error and recruitment_date: ["This field is required."] ,after searching i added the Date Formats on the settings but i still have the same error
views.py :
class CreateEmployee(generics.CreateAPIView):
lookup_field= 'pk'
serializer_class = EmployeeSerializer
def get_queryset(self):
return Employee.objects.all()
serializers.py :
class EmployeeSerializer(serializers.ModelSerializer):
url = serializers.SerializerMethodField(read_only=True)
recruitment_date =fields.DateField(format="%Y-%m-%d",input_formats=['%Y-%m-%d'])
class Meta:
model = Employee
fields =['url','id','f_name','l_name','job','telephone','recruitment_date','salary']
def get_url(self,obj):
request = self.context.get("request")
return obj.get_api_url(request=request)
settings.py :
"DATE_INPUT_FORMATS": ["iso-8601","%Y-%m-%d"],
Related
Updated
I changed my simplified question into a real example.
I've created a working post response of data from the model using ModelSerialzer, which I call from a post method in a view class. I would like to add additional data to the response. This is the pertinent code from my CBV:
def post(self, request, format=None):
user_profile = UserProfiles.objects.get(user=request.user.id)
service_id = user_profile.service_id
rec_filter = Recommendations.objects.values_list('resource')
if service_id > 0:
service_name = Services.objects.get(pk=service_id)
programs = Programs.objects.filter(services=service_id)
resources_filtered = Resources.objects.filter(program__in=programs).exclude(id__in=rec_filter)
else:
service_name = 'All Services'
resources_filtered = Resources.objects.exclude(id__in=rec_filter)
serializer = ResourceSerializer(resources_filtered, many=True)
#serializer.data["service"] = service_name
return Response(serializer.data)
The commented out line was my attempt to add data base on a similar post here. I get a 500 response in my API call. What is the correct way to do it? The response data is JSON if that's necessary to mention.
This is the ModelSerializer:
class ResourceSerializer(serializers.ModelSerializer):
organization = OrganizationSerializer(read_only=True)
program = ProgramSerializer(read_only=True)
class Meta:
model = Resources
fields = [
'organization',
'program',
'link',
'contact',
'general_contact',
'eligibility',
'service_detail'
]
Test of the answer
Heres the updated code based on the answer with a correction to fix and error:
class ResourceSerializer(serializers.ModelSerializer):
organization = OrganizationSerializer(read_only=True)
program = ProgramSerializer(read_only=True)
service = serializers.SerializerMethodField()
def get_service(self, obj):
return "All Services"
class Meta:
model = Resources
fields = [
'organization',
'program',
'link',
'contact',
'general_contact',
'eligibility',
'service_detail',
'service'
]
The problem with this approach is that the value "All Services" is repeated in every row serialized. It's only needed once. I'd also like to keep the data transmitted minimized.
The problem with the original attempt is that serializer.data is immutable. It's necessary to make a copy and add to it.
serializer = ResourceSerializer(resources_filtered, many=True)
augmented_serializer_data = list(serializer.data)
augmented_serializer_data.append({'service': 'All Services'})
return Response(augmented_serializer_data)
This answer is based on one given by #andre-machado in this question.
This code here is an example to coincide with the other answer given.
You can do it in serializer itself. Define the new field required and add it in fields. Mark all the fields in serializer from resource model.
class ResourceSerializer(serializers.ModelSerializer):
service = serializers.SerializerMethodField()
def get_service(self):
return "All Services"
class Meta :
model = Resources
fields = ('service') #Mark all the fields required here from resource model
You can do it from the serilaizer. In this case i was adding the field isOpen to the response and this is how i did it .timeDifference is the name of the function that was to generate data for the extra field . I hope it helps
class ShopSearchSerializer(serializers.ModelSerializer):
isOpen = serializers.SerializerMethodField('timeDifference')
def timeDifference(self,*args):
requestTime = datetime.now()
return requestTime
class Meta:
model = Shop
fields =['name','city','street','house','opening_time','closing_time','isOpen']
There are lot of answers related to custom fields on stackoverflow but when trying with them, I am getting different error, so posting a separate question.
I wanted to return a JSON Response for the following url
urls.py
path('cards/<int:pk>/smarts', smarts.as_view(), name="smarts"),
I will be using below api.py file to return aggregate fields using Transaction model, the query is working fine, I only have to return appropriate response. Here I have one of the fields as Decimal hence tried with DjangoJSONEncoder but got an error.
api.py
class smarts(generics.ListAPIView):
serializer_class = TransactionSerializer
permission_classes = [permissions.IsAuthenticated, TransactionIsOwnerOrNot]
def get_queryset(self):
card = get_object_or_404(self.request.user.cards, pk=self.kwargs['pk'])
qs=card.transactions.values('vendor').annotate(a=Count('pk'),b=Sum('amount')).order_by('-b')
....CODE REQUIRED
return ....
models.py
class Transactions(models.Model):
amount = models.DecimalField(max_digits=19, decimal_places=2)
vendor = models.CharField(max_length=200)
category = models.CharField(max_length=200)
owner = models.ForeignKey(Cards, on_delete=models.CASCADE, related_name="transactions",null=True)
serializer.py
class TransactionSerializer(serializers.ModelSerializer):
class Meta:
model = Transactions
fields = '__all__'
I found the answer after hit and trial, I used custom serializer to return required field.
serializer.py
class SmartSerializer(serializers.Serializer):
vendor = serializers.CharField(max_length=200)
tot = serializers.IntegerField()
tot_amt = serializers.DecimalField(max_digits=19, decimal_places=2)
api.py
class smartstatements(generics.ListAPIView):
permission_classes = [permissions.IsAuthenticated, TransactionIsOwnerOrNot]
serializer_class = SmartSerializer
def get_queryset(self):
card = get_object_or_404(self.request.user.cards, pk=self.kwargs['pk'])
queryset=card.transactions.values('vendor')
.annotate(tot=Count('pk'),tot_amt=Sum('amount'))
.order_by('-tot_amt')
return queryset
I'm running my own smart house project, using django backend with MySql on raspberry Pi.I've got SensorsData table in DB with thousands records with data from sensors. In my REST API I'm using view which looks like this:
#api_view(['GET'])
#permission_classes([IsAuthenticated])
def list_of_sensors_data(request, format=None):
"""
Get list of all sensors data, only for authenticated users
:param request: GET
:return: list of all sensors data if ok http 200 response
"""
sensors_data = SensorsData.objects.all()
serializer = SensorsDataSerializer(sensors_data, many=True)
return Response(serializer.data, status=status.HTTP_200_OK)
I've run perfomance test with locust simulating 10 users trying to use my endpoints. After some time, Django keeps returning 504 Timeout using this particular endpoint. My quest is, how can I optimize this queryset? I need to make it faster.
EDIT SensorsData model:
class SensorsData(models.Model):
sensor = models.ForeignKey(Sensors, on_delete=models.CASCADE)
delivery_time = models.DateTimeField(auto_now_add=True)
sensor_data = models.CharField(max_length=20)
class Meta:
verbose_name = "Sensor data"
verbose_name_plural = "Sensors data"
def __str__(self):
return f"{self.sensor.id}: {self.sensor.name}"
SensorsData Serializer:
class SensorsDataSerializer(serializers.ModelSerializer):
sensor = serializers.SlugRelatedField(read_only=False, many=False, slug_field='name', queryset=Sensors.objects.all())
class Meta:
model = SensorsData
fields = ("sensor", "delivery_time", "sensor_data")
This will introduce an N+1 problem, for each SensorsData object, you will make an additional query to fetch the related Sensor object. The good news is that you can use .select_related(…) [Django-doc] to let Django retrieve all related sensors in the same query:
#api_view(['GET'])
#permission_classes([IsAuthenticated])
def list_of_sensors_data(request, format=None):
sensors_data = SensorsData.objects.select_related('sensor')
serializer = SensorsDataSerializer(sensors_data, many=True)
return Response(serializer.data, status=status.HTTP_200_OK)
I have this models:
class Discipline(models.Model):
name = models.CharField(max_length=200)
class Lesson(models.Model):
discipline = models.ForeignKey(Discipline, on_delete=models.CASCADE, null=True)
date = models.DateField()
regular_slot = models.BooleanField(default=False)
And these serializers:
class DisciplineSerializer(serializers.ModelSerializer):
class Meta:
model = Discipline
fields = ('name')
class LessonSerializer(serializers.ModelSerializer):
discipline = serializers.RelatedField(source='Discipline', read_only=True);
class Meta:
model = Lesson
fields = ('discipline', 'date', 'regular_slot')
I have a view to process a JSON request and to save the data:
def cours_list(request):
if request.method == 'POST':
data = JSONParser().parse(request)
serializer = LessonSerializer(data=data)
if serializer.is_valid():
serializer.save()
return JSONResponse(serializer.data, status=201)
return JSONResponse(serializer.errors, status=400)
My JSON request is as follows:
{"discipline":"Mathematiques","date":"2017-12-03"}
However, I have an error saying that:
'Lesson' object has no attribute 'Discipline'
I believe this is because attribute discipline in Lesson refers only to the id and is not of type Discipline. I could'nt find how to solve this. Is the way I define foreignKey is not correct ?
How to insert a foreignKey reference here while I receive a Discipline object from the JSON request ?
I'm going to help you also with this :)
class DisciplineSerializer(serializers.ModelSerializer):
class Meta:
model = Discipline
fields = ('name')
class LessonSerializer(serializers.ModelSerializer):
discipline = DiscliplineSerializer()
class Meta:
model = Lesson
fields = ('discipline', 'date', 'regular_slot')
Doing this is enough as far as I know.
Edit: Reason of your error is that you write "source="Discipline"" but there is no field named Discipline in your Lesson model. Therefore, it gives an error.
There is a year data type in MySQL and there is no corresponding data field type in django ORM. Can I provide a custom field class to map data type for one specific RDBMS? If so, how can I do that?
I managed to find following solution which satisfies my needs (models.py):
from django.core.exceptions import FieldError
class YearField(models.Field):
def db_type(self, connection):
if connection.settings_dict['ENGINE'] == 'django.db.backends.mysql':
return 'year'
else:
raise FieldError
and then use the column datatype in models:
class Band(models.Model):
"""Music band"""
class Meta:
db_table = 'band'
name = models.CharField(max_length=64)
active_since = YearField()
active_until = YearField(null=True)
genres = models.ManyToManyField(Genre)
def __unicode__(self):
return self.name