Initial commit

byostorage/__init__.py

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+__VERSION__ = 0.1

byostorage/admin.py

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+from django.contrib import admin
+from . import models
+
+class UserStorageAdmin(admin.ModelAdmin):
+    list_display = ['name', 'storage', 'owner']
+
+admin.site.register(models.UserStorage, UserStorageAdmin)

byostorage/apps.py

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+from django.apps import AppConfig
+
+
+class ByostorageConfig(AppConfig):
+    name = 'byostorage'
+    verbose_name = 'Bring your own storage'

byostorage/migrations/0001_initial.py

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+# Generated by Django 3.1.1 on 2021-03-11 23:11
+
+from django.conf import settings
+from django.db import migrations, models
+import django.db.models.deletion
+
+
+class Migration(migrations.Migration):
+
+    initial = True
+
+    dependencies = [
+        migrations.swappable_dependency(settings.AUTH_USER_MODEL),
+    ]
+
+    operations = [
+        migrations.CreateModel(
+            name='UserStorage',
+            fields=[
+                ('id', models.AutoField(auto_created=True, primary_key=True, serialize=False, verbose_name='ID')),
+                ('name', models.SlugField(help_text='Storage tag', max_length=20)),
+                ('storage', models.CharField(help_text='Storage class for this instance', max_length=255)),
+                ('settings_data', models.TextField(help_text='JSON dict with key/value settings')),
+                ('owner', models.ForeignKey(blank=True, null=True, on_delete=django.db.models.deletion.CASCADE, to=settings.AUTH_USER_MODEL)),
+            ],
+        ),
+    ]

byostorage/models.py

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+from django.db import models
+from django.core.files.storage import get_storage_class
+import json
+
+class UserStorage(models.Model):
+    """ A user defined storage
+    """
+    owner = models.ForeignKey('auth.User', on_delete=models.CASCADE, null=True, blank=True)
+    name = models.SlugField(max_length=20, help_text="Storage tag")
+    storage = models.CharField(max_length=255, help_text="Storage class for this instance")
+    settings_data = models.TextField(help_text="JSON dict with key/value settings")
+
+    def instance(self):
+        return get_storage_class(self.storage)(**self.settings)
+
+    @property
+    def settings(self):
+        return json.loads(self.settings_data)

byostorage/storage.py

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+from django.core.files.storage import Storage
+
+class MultiStorage(Storage):
+    ''' Django storage class that proxies multiple storage classes.
+
+    Uses a name prefix to determine store e.g. 'images:foo/bar.jpg'
+    '''
+
+    def __init__(self, config=None):
+        self.config = config or getattr(settings, 'BRING_YOUR_OWN_STORAGE', {})
+        self._cache = {}
+
+    def get_storage(self, name):
+        if name not in self._cache:
+            config = self.config[name]
+            self._cache[name] = get_storage_class(config['storage'])(**config['settings'])
+        return self._cache[name]
+
+    def split(self, name):
+        return name.split(":", 1)
+
+    def _open(self, name, mode='rb'):
+        storage, p = self.split(name)
+        return self.get_storage(storage)._open(p, mode)
+
+    def _proxy(self, method, name, *args, **kwargs):
+        storage, p = self.split(name)
+        sname = getattr(self.get_storage(storage), method)(name, *args, **kwargs)
+        if sname is not None:
+            return f"{storage}:{sname}"
+
+
+    def _save(self, name, content, max_length=None):
+        return self._proxy('save', name, content, max_length)
+
+class BYOStorage(MultiStorage):
+    ''' Database driven Bring-Your-Own-Storage
+
+    Multiple storages can 
+    '''
+
+    def get_storage(self, name):
+        if name not in self._cache:
+
+            # use storage from config by default
+            if name in self.config:
+                return super(BYOStorage, self).get_storage(name)
+
+            from .models import UserStorage
+            obj = UserStorage.objects.get(name=name)
+            self._cache[name] = obj.instance()
+        return self._cache[name]