use of upload_to function when creating on object in django - django

Question

here is my model in django :
import os
def upload_location_buy(instance, filename):
ext = filename.split('.')[-1]
filename = '%s.%s' % (instance.name+"_"+str(random.randint(1000, 9999)), ext)
print(os.path.join('uploads', filename))
return os.path.join('uploads', filename)
class Buy(models.Model):
pic_front = models.ImageField(blank=True, upload_to=upload_location_buy,default='')
When i try :
b = Buy(pic_front="appartement_a.jpg")
b.save()
it does nothing exception linking the current pic in the current path, so not using the function in the model.
And when i do :
b = Buy(pic_front=upload_location_buy("appartement_a.jpg"))
b.save()
it give me an error because it seems to need the instance.
TypeError: upload_location_buy() missing 1 required positional
argument: 'filename'
How to create a buy object, giving it a picture and using the upload_location_buy whend doing it without the admin ?
When i upload a pic in the admin it works.
how to give it the instance name or do it correctly ?
this is this script :
import sys
import os
import django
from django.core.exceptions import ObjectDoesNotExist
sys.path.append("../../../testproject")
os.environ["DJANGO_SETTINGS_MODULE"] = "testproject.settings"
django.setup()
from on_plan.models import Buy
Buy.objects.all().delete()
b = Buy(pic_front=upload_location_buy("appartement_a.jpg"))
b.save()
The script is in the same directory as the file "appartement_a.jpg".
-on_plan/
-testproject/
-import_script.py
-appartement_a.jpg
-manage.py
if i do a :
file_to_save = open('appartement_a.jpg', 'r').read()
b = Buy(pic_front=file_to_save)
b.save()
i have a:
UnicodeDecodeError: 'utf-8' codec can't decode byte 0xff in position 0: invalid start byte
if i do a :
file_to_save = open('appartement_a.jpg', 'rb').read()
b = Buy(pic_front=file_to_save)
b.save()
i have a:
AttributeError: 'bytes' object has no attribute '_committed'
the solution is here:
import requests
import urllib.parse
import sys
import os
import django
import csv
import time
import random
from django.core.exceptions import ObjectDoesNotExist
sys.path.append("../../../sample_estate")
os.environ["DJANGO_SETTINGS_MODULE"] = "sample_estate.settings"
django.setup()
from django.core.files.base import File
from on_plan.models import Buy
file_to_save = open('appartement_a.jpg', 'rb')
b = Buy(pic_front=File(file_to_save))
b.save()

Answer 1

When you create a Buy object you need to pass file-obejct into pic_front attribute, but you try to pass only name of file.
from django.core.files.base import File
file_to_save = open('/path/to/appartement_a.jpg', 'r').read()
b = Buy(pic_front=File(file_to_save))
b.save()
If you get file from a form you may upload it like that:
b = Buy(pic_front=request.FILES['file'])
b.save()
Anyway pic_front expect to getting a file-object not string
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