First attempt at making config loadable through string config overrides in an env variable.

storage/__init__.py

@@ -0,0 +1,36 @@
+from storage.local import LocalStorage
+from storage.s3 import S3Storage
+from storage.fakestorage import FakeStorage
+
+
+class Storage(object):
+  def __init__(self, app=None):
+    self.app = app
+    if app is not None:
+      self.state = self.init_app(app)
+    else:
+      self.state = None
+
+  def init_app(self, app):
+    storage_type = app.config.get('STORAGE_TYPE', 'LocalStorage')
+    path = app.config.get('STORAGE_PATH', '')
+
+    if storage_type == 'LocalStorage':
+      storage = LocalStorage(path)
+
+    elif storage_type == 'S3Storage':
+      access_key = app.config.get('STORAGE_AWS_ACCESS_KEY', '')
+      secret_key = app.config.get('STORAGE_AWS_SECRET_KEY', '')
+      bucket = app.config.get('STORAGE_S3_BUCKET', '')
+      storage = S3Storage(path, access_key, secret_key, bucket)
+
+    else:
+      storage = FakeStorage()
+
+    # register extension with app
+    app.extensions = getattr(app, 'extensions', {})
+    app.extensions['storage'] = storage
+    return storage
+
+  def __getattr__(self, name):
+    return getattr(self.state, name, None)