Django ImageField change file name on upload

Question

Upon saving me model \'Products\' I would like the uploaded image to be named the same as the pk for example 22.png or 34.gif I don\'t want to change the format of the image jus

Answer 1

You can pass a function into upload_to field:

def f(instance, filename):
    ext = filename.split('.')[-1]
    if instance.pk:
        return '{}.{}'.format(instance.pk, ext)
    else:
        pass
        # do something if pk is not there yet

My suggestions would be to return a random filename instead of {pk}.{ext}. As a bonus, it will be more secure.

What happens is that Django will call this function to determine where the file should be uploaded to. That means that your function is responsible for returning the whole path of the file including the filename. Below is modified function where you can specify where to upload to and how to use it:

import os
from uuid import uuid4

def path_and_rename(path):
    def wrapper(instance, filename):
        ext = filename.split('.')[-1]
        # get filename
        if instance.pk:
            filename = '{}.{}'.format(instance.pk, ext)
        else:
            # set filename as random string
            filename = '{}.{}'.format(uuid4().hex, ext)
        # return the whole path to the file
        return os.path.join(path, filename)
    return wrapper

FileField(upload_to=path_and_rename('upload/here/'), ...)