Comenzando a utilizar SQLAlchemy

Tuve que reescribir bastante para lograrlo, pero ya funciona :3

files/__init__.py

@@ -3,42 +3,45 @@ import os
 from flask import Flask, render_template
 from werkzeug import SharedDataMiddleware
 
+
 def create_app():
     app = Flask(__name__, instance_relative_config=True)
 
     app.config.from_mapping(
-        DATABASE = os.path.join(app.instance_path, 'files.sqlite'),
-        USERNAME = 'dev',
-        PASSWORD = 'secret',
-        SECRET_KEY = '1337',
-        UPLOAD_FOLDER = 'uploads',
-        ALLOWED_EXTENSIONS = set(['png', 'jpg'])
+        SQLALCHEMY_DATABASE_URI="sqlite:///{}".format(os.path.join(app.instance_path, 'files.sqlite')),
+        SQLALCHEMY_TRACK_MODIFICATIONS=False,
+        USERNAME='dev',
+        PASSWORD='secret',
+        SECRET_KEY='1337',
+        UPLOAD_FOLDER='uploads'
     )
 
     app.config.from_pyfile('config.py')
-    app.wsgi_app = SharedDataMiddleware(app.wsgi_app, { '/uploads': app.config['UPLOAD_FOLDER'] })
+    app.wsgi_app = SharedDataMiddleware(app.wsgi_app, {'/uploads': app.config['UPLOAD_FOLDER']})
 
     try:
         os.makedirs(app.instance_path)
     except OSError:
         pass
 
-    from . import db
+    from files.models import db
     db.init_app(app)
 
-    from . import auth
+    from files import commands
+    commands.init_app(app)
+
+    from files import auth
     app.register_blueprint(auth.bp)
 
-    from . import categories
+    from files import categories
     app.register_blueprint(categories.bp)
 
-    from . import about
+    from files import about
     app.register_blueprint(about.bp)
     app.add_url_rule('/about', endpoint='about')
 
-    from . import files
+    from files import files
     app.register_blueprint(files.bp)
     app.add_url_rule('/', endpoint='index')
 
-
     return app