Bulk create on related models using csv - django

Question

I'm trying to use bulk_create in order to add objects to related models. Here i'm fetching the csv file through post request which contains required fields. As of now I can add items to models which is unrelated using the csv file and bulk_create and it's working.
class BulkAPI(APIView):
def post(self, request):
paramFile = io.TextIOWrapper(request.FILES['requirementfile'].file)
dict1 = csv.DictReader(paramFile)
list_of_dict = list(dict1)
objs = [
ManpowerRequirement(
project=row['project'],
position=row['position'],
quantity=row['quantity'],
project_location=row['project_location'],
requested_date=row['requested_date'],
required_date=row['required_date'],
employment_type=row['employment_type'],
duration=row['duration'],
visa_type=row['visa_type'],
remarks=row['remarks'],
)
for row in list_of_dict
]
try:
msg = ManpowerRequirement.objects.bulk_create(objs)
returnmsg = {"status_code": 200}
print('imported successfully')
except Exception as e:
print('Error While Importing Data: ', e)
returnmsg = {"status_code": 500}
return JsonResponse(returnmsg)
My models are:
class ManpowerRequirement(models.Model):
project = models.CharField(max_length=60)
position = models.CharField(max_length=60)
quantity = models.IntegerField()
project_location = models.CharField(max_length=60)
requested_date = models.DateField()
required_date = models.DateField()
employment_type = models.CharField(max_length=60,choices = EMPLOYMENT_TYPE_CHOICES,
default = 'Permanent')
duration = models.CharField(max_length=60)
visa_type = models.CharField(max_length=60)
remarks = models.TextField(blank = True , null=True)
def __str__(self):
return self.project
class Meta:
verbose_name_plural = "Manpower_Requirement"
class Fulfillment(models.Model):
candidate_name = models.CharField(max_length=60)
manpower_requirement = models.ForeignKey(ManpowerRequirement, on_delete=models.CASCADE)
passport_number = models.CharField(blank = True, max_length=60)
subcontract_vendors = models.CharField(max_length=200,blank = True , null=True ,default='')
joined_date = models.DateField(blank = True, null = True, default = '')
remarks = models.TextField( blank = True,null = True)
def __str__(self):
return self.candidate_name
class Meta:
verbose_name_plural = "Fulfillment"
class FulfillmentStatus(models.Model):
fulfillment = models.ForeignKey(Fulfillment, on_delete=models.CASCADE)
status = models.CharField(max_length=60)
status_date = models.DateField()
remarks = models.TextField( blank = True, null = True )
def __str__(self):
return self.fulfillment.candidate_name
class Meta:
verbose_name_plural = "FulfillmentStatus"
I don't know how to do the same using bulk_create for Fulfillment and FulfillmentStatus models which are related to ManpowerRequirement. Csv file which I recieve in order to bulkcreate for Fulfillment consists of all the fields of ManpowerRequirement and all fields of Fulfillment and FulfillmentStatus excluding the foreign keys and id fields.

Answer 1

in the past I had the same problem; I solved in that way
Assuming that in a single CSV row you have data for all models I'd go for
create a mapping between the main model and the linked ones (you could use row index as key
use bulk_create() on the main model
iterate the dict and use bulk_create() for the linked modules
items = []
mrs = []
for row in list_of_dict:
mr = ManpowerRequirement(...)
mrs.append(mr)
f = ManpowerRequirement(...)
fs = FulfillmentStatus(...)
items.append((mr, f, fs))
# create all Manpower Requirements
ManpowerRequirements.objects.bulk_create(mrs)
a = []
for mr, f, fs in items:
f.manpower_requirement = mr
a.append(f)
# create all Fulfillments
Fulfillment.objects.bulk_create(a)
a = []
for mr, f, fs in items:
fs.fulfillment = f
a.append(fs)
# create all FulfillmentStatus
FulfillmentStatus.objects.bulk_create(a)
not sure if you can do some optimization in looping but it should solve the problem with just 3 queries

Answer 2

For related models we can do like this
class FulfillmentAPI(APIView):
def post(self, request):
paramFile = io.TextIOWrapper(request.FILES['fulfillmentfile'].file)
dict1 = csv.DictReader(paramFile)
list_of_dict = list(dict1)
objs = [
Fulfillment(
manpower_requirement=ManpowerRequirement.objects.get(project=row['project'], position=row['position'], quantity=row['quantity'], requested_date=row['requested_date'],),
remarks=row['remarks'],
candidate_name=row['candidate_name'],
passport_number=row['passport_number'],
joined_date=row['joined_date'],
subcontract_vendors=row['subcontract_vendors'],
)
for row in list_of_dict
]
try:
msg = Fulfillment.objects.bulk_create(objs)
returnmsg = {"status_code": 200}
print('imported successfully')
except Exception as e:
print('Error While Importing Data: ', e)
returnmsg = {"status_code": 500}
return JsonResponse(returnmsg)