Well, this works

royalnet/royalgamesweb.py

@@ -0,0 +1,12 @@
+import os
+from .web import create_app
+from .web.blueprints import helloworld
+
+
+class TestConfig:
+    DB_PATH = os.environ["DB_PATH"]
+    REQUIRED_TABLES = set()
+
+
+app = create_app(TestConfig, [helloworld.bp])
+app.run()

royalnet/web/__init__.py

@@ -0,0 +1,3 @@
+from .flaskserver import create_app
+
+__all__ = ["create_app"]

royalnet/web/alchemyhandler.py

@@ -4,12 +4,12 @@ import werkzeug.local
 
 def get_alchemy_session():
     if "alchemy_session" not in f.g:
-        f.g.alchemy_session = f.current_app.config["RN_ALCHEMY"].Session()
+        f.g.alchemy_session = f.g.alchemy.Session()
     return f.g.alchemy_session
 
 
 @f.current_app.teardown_appcontext
-def teardown_alchemy_session(*args, **kwargs):
+def teardown_alchemy_session(*_, **__):
     _alchemy_session = f.g.pop("alchemy_session", None)
     if _alchemy_session is not None:
         _alchemy_session.close()

royalnet/web/blueprints/helloworld.py

@@ -0,0 +1,9 @@
+import flask as f
+
+
+bp = f.Blueprint("helloworld", __name__, url_prefix="/helloworld")
+
+
+@bp.route("/")
+def helloworld():
+    return "Hello world!"

royalnet/web/flaskserver.py

@@ -1,19 +1,13 @@
+import typing
 import flask as f
-import os
 from ..database import Alchemy
 
 
-app = f.Flask(__name__)
-app.config["RN_ALCHEMY"] = Alchemy(os.environ["DB_PATH"], set())
-with app.app_context():
-    from .alchemyhandler import alchemy_session as db_session
-
-
-@app.route("/")
-def test():
-    ...
-    return repr(db_session)
-
-
-if __name__ == "__main__":
-    app.run()
+def create_app(config_obj: typing.Type, blueprints: typing.List[f.Blueprint]):
+    app = f.Flask(__name__)
+    app.config.from_object(config_obj)
+    with app.app_context():
+        f.g.alchemy = Alchemy(app.config["DB_PATH"], app.config["REQUIRED_TABLES"])
+    for blueprint in blueprints:
+        app.register_blueprint(blueprint)
+    return app