Django Rest Framework get attributes from foreign key's class - django

here's my models:
class Recruteur(models.Model):
entrepriseName = models.CharField(max_length=50)
emplacement = models.CharField(max_length=50)
class Offre(models.Model):
title = models.CharField(max_length=100, blank=True, default=0)
idRecruteur = models.ForeignKey(Recruteur,verbose_name = "idRecruteur", on_delete=models.CASCADE, default=None)
and here's my api.py:
class VilleViewSet(ModelViewSet):
queryset = Offre.objects.values('idRecruteur__emplacement').distinct()
serializer_class = VilleSerializer
serializers.py:
class EmplacementSerializer(serializers.ModelSerializer):
class Meta:
model = Recruteur
fields = ('emplacement',)
class VilleSerializer(serializers.ModelSerializer):
emplacements = EmplacementSerializer(source='idRecruteur', read_only=True)
class Meta:
model = Offre
fields = ( 'emplacements',)
i was expecting a result like this
but i got nothing instead ..
Any ideas why?

You get nothing, because there is no emplacements field in Offre model. I guess, what you want is to get serialized Recruteur record, that is referenced by idRecruteur field. Try this:
class VilleSerializer(serializers.ModelSerializer):
idRecruteur = EmplacementSerializer(read_only=True)
class Meta:
model = Offre
fields = ( 'idRecruteur',)

Related

django-import-export how to deal with the import_id_fields is unique_together key?

the parentmodel is
class Work(models.Model):
po = models.ForeignKey(Po, verbose_name="合同号", on_delete=models.CASCADE)
remark = models.CharField(max_length=100, verbose_name="备注说明")
create_time=models.DateField(verbose_name="日期")
class Meta:
verbose_name = "工作清单"
verbose_name_plural = verbose_name
unique_together=("po","remark")
def __str__(self):
return self.remark
and the children model is
class Acceptance(models.Model):
work = models.ForeignKey(Work, on_delete=models.CASCADE, verbose_name="工作清单")
detail=models.ForeignKey(Detail,on_delete=models.CASCADE,verbose_name="验收物品")
accecpt_time = models.DateField(verbose_name="验收日期")
num = models.IntegerField(verbose_name="验收数量", validators=[MinValueValidator(1)])
person = models.CharField(max_length=100, verbose_name="验收人员")
class Meta:
verbose_name = "验收清单"
verbose_name_plural = verbose_name
unique_together=("accecpt_time","work")
I want to ask about how to defind the Acceptance Resource when the work foreign_key is unique_together key?
my test code is
class AcceptanceSource(resources.ModelResource):
work = fields.Field(attribute="work", widget=ForeignKeyWidget(Work, 'remark'), column_name="工作清单")
detail = fields.Field(attribute="detail", widget=ForeignKeyWidget(Detail, "name"), column_name="物料清单")
po = fields.Field(attribute="work__po", column_name="合同号", widget=ForeignKeyWidget(Po, "po_num"))
num = fields.Field(attribute="num", column_name="验收数量")
accecpt_time = fields.Field(attribute="accecpt_time", column_name="验收时间")
person = fields.Field(attribute="person", column_name="验收人员")
but it get error like this:
行号: 1 - get() returned more than one Work -- it returned 2!

How to add nested field after creating the ModelSerializer? Not in the class

Basically i want to have fk_inventory as a nested field in StorageRackSerializer but as you guys can see I also need to use StorageRackSerializer in InventorySerializer.
How can i set the field after creating the serializer class?
I have tried creating a fk_inventory field and set it to None and tried to set to InventorySerializer afterwards but didn't work.
class Inventory(models.Model):
inventory_id = models.AutoField(primary_key=True)
fk_building = models.OneToOneField(Store, on_delete=models.CASCADE, unique=True, related_name='inventory')
def __str__(self):
return f"{self.inventory_id}"
class StorageRack(models.Model):
storage_rack_id = models.AutoField(primary_key=True)
quantity = models.IntegerField(default=0, validators=[MinValueValidator(0), MaxValueValidator(50)])
fk_inventory = models.ForeignKey(Inventory, on_delete=models.CASCADE, related_name="storage_racks")
fk_product_id = models.ForeignKey(Product, on_delete=models.SET_NULL, null=True, related_name="storage_racks")
def __str__(self):
return f"{self.storage_rack_id}"
class StorageRackSerializer(serializers.ModelSerializer):
fk_product_id = ProductSerializer(read_only=True)
fk_inventory = None
class Meta:
model = StorageRack
fields = ('storage_rack_id', 'quantity', 'fk_inventory', 'fk_product_id')
class InventorySerializer(serializers.ModelSerializer):
fk_building = StoreSerializer()
storage_racks = StorageRackSerializer(many=True)
class Meta:
model = Inventory
fields = ('inventory_id', 'fk_building', 'storage_racks')
StorageRackSerializer.fk_inventory = InventorySerializer()
You can add a field 'fk_inventory' in the validated data from SorageRackSerializer
validated_data = StorageRackSerializer(data=data)
validated_data['fk_inventory'] = InventorySerializer().data

checking if a certain many to many foreign key is present on django-polymorphic models

So in order to create an object model, I have to first see if a supplier has a relation of type many to many from BusinessModel, WarehouseModel or StoreModel to in a django-polymorphic
My main idea is to check if BusinessModel, which is connected to Order through BusinessOrderModel, StoreModel, which is connected to Order through StoreOrderModel or WarehouseModel which is connected directly to Order, have FKs on a many to many relationship going to the article that we want to order through a POST request.
class ArticleModel(models.Model):
id = models.AutoField(primary_key=True)
code = models.IntegerField(unique=True)
description = models.TextField()
def __str__(self):
return str(self.code)
class OrderModel(models.Model):
id = models.AutoField(primary_key=True)
order_to = models.ForeignKey('OrderToModel', on_delete=models.CASCADE)
article = models.ForeignKey('ArticleModel', on_delete=models.CASCADE)
quantity= models.IntegerField()
class OrderToModel(PolymorphicModel):
id = models.AutoField(primary_key=True)
class WarehouseModel(OrderToModel):
warehouse_num = models.IntegerField(unique=True)
name = models.CharField(max_length=100)
address = models.TextField()
articles = models.ManyToManyField(ArticleModel)
def __str__(self):
return "Warehouse"+ str(self.warehouse_num)
class StoreOrderModel(OrderToModel):
reference = models.IntegerField(unique=True)
store_num = models.ForeignKey('StoreModel', on_delete=models.CASCADE)
def __str__(self):
return str(self.reference)
class StoreModel(models.Model):
store_num = models.IntegerField(primary_key=True)
name = models.CharField(max_length=100)
address = models.TextField()
articles = models.ManyToManyField(ArticleModel)
def __str__(self):
return str(self.store_num)
class BusinessOrderModel(OrderToModel):
reference = models.IntegerField(unique=True)
business_num = models.ForeignKey('BusinessModel', on_delete=models.CASCADE)
def __str__(self):
return str(self.reference)
class BusinessModel(models.Model):
Business_num = models.IntegerField(primary_key=True)
name = models.CharField(max_length=100)
address = models.TextField()
articles = models.ManyToManyField(ArticleModel)
def __str__(self):
return str(self.Business_num)
Here's my serializers:
class WarehouseSerializer(serializers.ModelSerializer):
class Meta:
model = WarehouseModel
fields = ('id', 'warehouse_num')
class StoreOrderSerializer(serializers.ModelSerializer):
class Meta:
model = StoreOrderModel
fields = ('id', 'reference', 'store_num')
class DetailSerializer(serializers.ModelSerializer):
class Meta:
model = DetailModel
fields = ('id', 'detail')
class BusinessOrderSerializer(serializers.ModelSerializer):
details = DetailSerializer(many=True, read_only=True)
class Meta:
model = BusinessOrderModel
fields = ('reference', 'business_num','details')
class OrderToPolymorphicSerializer(PolymorphicSerializer):
model_serializer_mapping = {
WarehouseModel: WarehouseSerializer,
StoreOrderModel: StoreOrderSerializer,
BusinessOrderModel: BusinessOrderSerializer
}
and here's my view:
class OrderCreateView(generics.CreateAPIView):
queryset = OrderModel.objects.all()
serializer_class = OrderCreateSerializer

How to do a relationship using DRF to another table without foreignKey

I can not do relatioships between two tables without relationships.
My models are :
class exampleModel(models.Model):
quantity = models.IntegerField(blank=False, null=True)
comment = models.CharField(max_length=100 , blank=True, null=True)
class Meta:
db_table = "example"
class Logger(models.Model):
id_table = models.IntegerField()
table = models.CharField(max_length=20 , blank=True, null=True)
comment = models.CharField(max_length=100 , blank=True, null=True)
action = models.CharField(max_length=100 , blank=True, null=True)
date_created = models.DateTimeField(auto_now_add=True)
class Meta:
db_table = "logger"
I already have filled logger Model, but , I have not be able made the exampleSerializer.
My serializers are:
class LoggerSerializer(serializers.ModelSerializer):
class Meta:
db_table = u'logger'
model = Logger
fields = '__all__'
class exampleSerializer(serializers.ModelSerializer):
last_log = LoggerSerializer(read_only=True)
class Meta:
db_table = 'example'
model = ExampleModel
fields = ( 'id' , 'last_log' , 'quantity')
in logger saves :
id_table : 'primary key of example',
table : 'example'
comment : 'custom comment',
action : "CRUD"
You can query last logger in view, then pass it to serializer in context.
Then do something like:
class exampleSerializer(serializers.ModelSerializer):
last_log = serializers.SerializerMethodField()
class Meta:
db_table = 'example'
model = ExampleModel
fields = ('id', 'last_log', 'quantity')
def get_last_log(self, obj):
last_log = obj.state(self.context['last_log'])
last_log_serializer = LoggerSerializer(last_log)
return last_log_serializer.data
You pass to context, with something like:
exampleSerializer(queryset, context ={'last_log': last_log_object})
Also You can do the query in exampleSerializer:
class exampleSerializer(serializers.ModelSerializer):
last_log = serializers.SerializerMethodField()
class Meta:
db_table = 'example'
model = ExampleModel
fields = ('id', 'last_log', 'quantity')
def get_last_log(self, obj):
logger_queryset =Logger.objects.filter(table = self.Meta.db_table, id_table = obj.id)
return LoggerSerializer(logger_queryset).data

Nested serializers in drf throws error with one to one field

My input json is :
{
"availability": "Current",
"drive_type": [{
"drive_name": "drive1",
"requirements": {
"performance_unit": "by_iops",
}
}]
}
I am getting error Cannot assign "
OrderedDict([('performance_unit', 'Basic')])":
"DriveType.requirements" must be a "Requirements" instance
.I am not able to figure it out to map in create method for one to one fields in tables
Below are my models.py
class ProductLine(models.Model):
availability = models.CharField(max_length=20, blank=True, null=True)
class Meta:
db_table = "product_line"
class DriveType(models.Model):
drive_name = models.CharField(max_length=20, blank=True, null=True)
product_line = models.ForeignKey(ProductLine, related_name="drive_type")
class Meta:
db_table = "drive_type"
class Requirements(models.Model):
performance_unit = models.CharField(max_length=100, blank=True, null=True)
drive_type = models.OneToOneField(DriveType,on_delete=models.CASCADE,primary_key=True,related_name="requirements")
class Meta:
db_table = "requirements"
Serializers.py :
class DriveTypeSerializer(serializers.ModelSerializer):
requirements = RequirementsSerializer(many = True)
class Meta:
model = DriveType
fields = (
"drive_name","workload_type")
class ProductLineSerializer(serializers.ModelSerializer):
drive_type = DriveTypeSerializer(many=True)
class Meta:
model = ProductLine
fields = ('availability', "drive_type")
def create(self, validated_data):
print("validate_data",validated_data)
drive_type_data = validated_data.pop("drive_type")
product_line = ProductLine.objects.create(**validated_data)
for drive_data in drive_type_data:
drive_type = DriveType.objects.create(product_line=product_line, **drive_data)
return product_line
You have one to one relationship of DriveType and Requirements
So remove many = True from DriveTypeSerializer for RequirementsSerializer
class DriveTypeSerializer(serializers.ModelSerializer):
requirements = RequirementsSerializer()
class Meta:
model = DriveType
fields = ("drive_name","workload_type")
Your input json has only one object of requirements not a list