django-s3-file-field
django-s3-file-field is a Django library for uploading files directly to
AWS S3 or MinIO Storage from HTTP clients
(browsers, CLIs, etc.).
Benefits
django-s3-file-field makes long-running file transfers (with large files or slow connections)
more efficient, as the file content is no longer proxied through the Django server. This also frees
Django from needing to maintain active HTTP requests during file upload, decreasing server load and
facilitating deployment to environments like
Heroku, which have short, strict request timeouts.
Scope
The principal API of django-s3-file-field is the S3FileField
, which is a subclass of
Django's FileField
.
django-s3-file-field does not affect any operations other than uploading from external HTTP
clients; for all other file operations (downloading, uploading from the Python API, etc.), refer to
Django's file management documentation.
django-s3-file-field supports both the creation and modification (by overwrite) of
S3FileField
-containing Model
instances.
It supports server-rendered views, via the Forms API, with Form Field
and Widget
subclasses
which will automatically be used for ModelForm
instances.
It also supports RESTful APIs, via Django Rest Framework's Serializer API, with a
Serializer Field
subclass which will automatically be used for ModelSerializer
instances.
Installation
django-s3-file-field must be used with a compatible Django Storage, which are:
After the appropriate Storage is installed and configured, install django-s3-file-field, using the
corresponding extra:
pip install django-s3-file-field[s3]
or
pip install django-s3-file-field[minio]
Enable django-s3-file-field as an installed Django app:
INSTALLED_APPS = [
...,
's3_file_field',
]
Add django-s3-file-field's URLconf to the root URLconf; the path prefix ('api/s3-upload/'
)
can be changed arbitrarily as desired:
from django.urls import include, path
urlpatterns = [
...,
path('api/s3-upload/', include('s3_file_field.urls')),
]
Usage
For all usage, define an S3FileField
on a Django Model
, instead of a FileField
:
from django.db import models
from s3_file_field import S3FileField
class Resource(models.Model):
blob = S3FileField()
Django Forms
When defining a
Django ModelForm
,
the appropriate Form Field
will be automatically used:
from django.forms import ModelForm
from .models import Resource
class ResourceForm(ModelForm):
class Meta:
model = Resource
fields = ['blob']
Forms using django-s3-file-field include additional
assets, which it's essential to render
along with the Form. Typically, this can be done in any Form-containing Template as:
<head>
{# Assuming the Form is availible in context as "form" #}
{{ form.media }}
</head>
Django Rest Framework
When defining a
Django Rest Framework ModelSerializer
,
the appropriate Serializer Field
will be automatically used:
from rest_framework import serializers
from .models import Resource
class ResourceSerializer(serializers.ModelSerializer):
class Meta:
model = Resource
fields = ['blob']
Clients interacting with these RESTful APIs will need to use a corresponding django-s3-file-field
client library. Client libraries (and associated documentation) are available for:
Pytest
When installed, django-s3-file-field makes several
Pytest fixtures automatically
available for use.
The s3ff_field_value
fixture will return a valid input value for Django ModelForm
or
Django Rest Framework ModelSerializer
subclasses:
from .forms import ResourceForm
def test_resource_form(s3ff_field_value: str) -> None:
form = ResourceForm(data={'blob': s3ff_field_value})
assert form.is_valid()
Alternatively, the s3ff_field_value_factory
fixture transforms a File
object into a valid input
value (for Django ModelForm
or Django Rest Framework ModelSerializer
subclasses), providing
more control over the uploaded file:
from django.core.files.storage import default_storage
from rest_framework.test import APIClient
def test_resource_create(s3ff_field_value_factory):
client = APIClient()
stored_file = default_storage.open('some_existing_file.txt')
s3ff_field_value = s3ff_field_value_factory(stored_file)
resp = client.post('/resource', data={'blob': s3ff_field_value})
assert resp.status_code == 201