Skip to content

Instantly share code, notes, and snippets.

What would you like to do?
Base64 file handling for django-tastypie
import base64
import os
from tastypie.fields import FileField
from django.core.files.uploadedfile import SimpleUploadedFile
class Base64FileField(FileField):
A django-tastypie field for handling file-uploads through raw post data.
It uses base64 for en-/decoding the contents of the file.
class MyResource(ModelResource):
file_field = Base64FileField("file_field")
class Meta:
queryset = ModelWithFileField.objects.all()
In the case of multipart for submission, it would also pass the filename.
By using a raw post data stream, we have to pass the filename within our
file_field structure:
file_field = {
"name": "myfile.png",
"file": "longbas64encodedstring",
"content_type": "image/png" # on hydrate optional
def dehydrate(self, bundle):
if not and hasattr(bundle.obj, self.instance_name):
file_field = getattr(bundle.obj, self.instance_name)
if file_field:
content_type, encoding = mimetypes.guess_type(
b64 = open(, "rb").read().encode("base64")
ret = {
"name": os.path.basename(,
"file": b64,
"content-type": content_type or "application/octet-stream"
return ret
return None
def hydrate(self, obj):
value = super(FileField, self).hydrate(obj)
if value:
value = SimpleUploadedFile(value["name"], base64.b64decode(value["file"]), getattr(value, "content_type", "application/octet-stream"))
return value
Copy link

klipstein commented Nov 22, 2010

An alternative for passing the filename would be to use a data uri


Copy link

miratcan commented Jun 30, 2011

That field saves file to database or disk?

Copy link

klipstein commented Jun 30, 2011

If you POST/PUT the Base64 file string to a tastypie-resource that is using this Base64FileField it'll turn the Base64 string into an UploadedFile object that then can be used by directly. Depending on your storage-backend of your model's file field it then either saves the file to your disk+reference string to your db (default) or to another location which is defined in your storage class.

Copy link

miratcan commented Jun 30, 2011

Ah i see now, very nice thanks :)

Copy link

moshevolo commented Jul 2, 2012

Anyone can provide some more info on how to use this solution?
I have a form with a file field in and then a model with a fiel field in
Do I need to create another file with the above class, and then how do I use it with the form or with the model?
Is the right thing to do is to use Base64FileField instead of FileField in my form or in my model?
And lastly when does dehydrate function actually get called?
Here is the section from

class DocumentUploadForm(forms.Form):
document_name = forms.CharField(max_length=30, required=False)
description = forms.CharField(widget=forms.Textarea(attrs={'cols': 60, 'rows': 4}), required=False)
docfile = forms.FileField(label='Select a file', help_text='max. 40 megabytes')

And here is the section from
class Document(models.Model):
document_name = models.CharField(max_length=30, null=True)
description = models.TextField(null=True)
document = models.FileField(upload_to='documents/%Y/%m/%d')


Copy link

dcale commented Jun 10, 2013

Hey klipstein, thank you for this! In the current tastypie version (django-tastypie==0.9.15) you have to make a little change for this to work, otherwise you'll get an "dehydrate() got an unexpected keyword argument 'for_list'" exception:

def dehydrate(self, bundle):

def dehydrate(self, bundle, for_list):

Copy link

yuvadm commented Feb 3, 2014

Also missing:

import mimetypes

Copy link

th0th commented Sep 28, 2014

Any hints on checking resolution of the incoming file when using this for an image?

Sign up for free to join this conversation on GitHub. Already have an account? Sign in to comment