Django model not updating image field correctly (Raw content)

[Marisol Cardozo]

My model:

class MyModel(models.Model):
    picture = models.ImageField(blank=True, null=True, upload_to='pictures')

Update a single object:

>>> picture
>>> <ContentFile: Raw content>
>>> mymodel = MyModel.objects.get(pk=instance.pk)
>>> mymodel.picture = picture
>>> mymodel.save()
>>> mymodel.picture
>>> <ImageFieldFile: pictures/fbdfe25b-b246-4f2d-9436-dca49aef88d7.png>

Good. Url result /media/pictures/fbdfe25b-b246-4f2d-9436-dca49aef88d7.png.

Update a single object with the update() method:

>>> picture
>>> <ContentFile: Raw content>
>>> MyModel.objects.filter(pk=instance.pk).update(picture=picture)
>>> mymodel = MyModel.objects.get(pk=instance.pk)
>>> mymodel.picture
>>> <ImageFieldFile: Raw content>

Bad. Url result: /media/Raw%20content.

[Mariusz Felisiak]

You cannot use .update() for updating a FileField/ImageField, in that way you will update only a filename in the database. You should use ​FieldFile.save(). If you're having trouble understanding how Django works, see TicketClosingReasons/UseSupportChannels for ways to get help. There is also an open ticket #29607 for adding extra examples to the "Managing files" topic.