How to assign a local file to the FileField in Django?

Question

I was trying to assign a file from my disk to the FileField, but I have this error:

AttributeError: 'str' object has no attribute 'open'

My python code:

pdfImage = FileSaver()
pdfImage.myfile.save('new', open('mytest.pdf').read())

and my models.py

class FileSaver(models.Model):

    myfile = models.FileField(upload_to="files/")

    class Meta:
        managed=False

Thank you in advance for your help

Dewdrop

Answer 1

Django uses it's own file type (with a sightly enhanced functionality). Anyway Django's file type works like a decorator, so you can simply wrap it around existing file objects to meet the needs of the Django API.

from django.core.files import File

local_file = open('mytest.pdf')
djangofile = File(local_file)
pdfImage.myfile.save('new', djangofile)
local_file.close()

You can of course decorate the file on the fly by writing the following (one line less):

pdfImage.myfile.save('new', File(local_file))

Oscilloscope

overwriting <type 'file'> is probably a bad idea. Better to use file_ – Mise

Just to explain the above comment (I was confused for a bit) Aaron is talking about the symbol file (i.e. the name of the variable) rather than the type of argument passed. – Petasus

Remember to close both the python file object, and the Django File object. – Exhilaration

If you get a UnicodeDecodeError, try open the file in binary mode: local_file = open("mytest.pdf", "rb"). – Jaclin

As the "file" variable was renamed to "local_file" in the answer, @AaronMcMillin ' s comment doesn't make sense anymore. – Strontianite

Answer 2

If you don't want to open the file, you can also move the file to the media folder and directly set myfile.name with the relative path to MEDIA_ROOT :

import os
os.rename('mytest.pdf', '/media/files/mytest.pdf')
pdfImage = FileSaver()
pdfImage.myfile.name = '/files/mytest.pdf'
pdfImage.save()

Adsorb

Answer 3

If you want to upload a local file in django, you can do this

from django.core.files import File

file = open(filepath, 'rb')
file_to_upload = File(file, name=f'{your_desired_name}')
file.close()

Now you can pass the file to django rest serializer to upload or whatever your use-case is. If passing this file to serializer, be sure to close it after it has been passed to serializer.

Note: The filepath here can be django's temporary file or any stored file.

Loth

Answer 4

if you are getting error like:

UnicodeDecodeError: 'utf-8' codec can't decode byte 0x89 in position...

then you have to open the file in binary mode: open("mytest.pdf", "rb")

full example:

from django.core.files import File

pdfImage = FileSaver()
pdfImage.myfile.save('new.pdf', File(open('mytest.pdf','rb')))

Florescence