Setup oso, add policy.

app/__init__.py

@@ -1,7 +1,12 @@
 """Entrypoint to the expenses application"""
+from pathlib import Path
+
 from flask import Flask
 from flask_graphql import GraphQLView
 
+from oso import Oso
+from sqlalchemy_oso import register_models
+
 from .models import db
 from .schema import schema
 
@@ -24,6 +29,12 @@ def create_app(test_config=None):
     app.register_blueprint(user.bp)
     app.register_blueprint(sql.bp)
 
+    oso = Oso()
+    register_models(oso, db.Model)
+    oso.load_file(Path(__file__).parent / "policy.polar")
+
+    app.oso = oso
+
     return app
 
 

app/models.py

@@ -1,8 +1,15 @@
+from flask import g, current_app, request
 from flask_sqlalchemy import SQLAlchemy
 
 from sqlalchemy.orm import relationship
 
-db = SQLAlchemy()
+from sqlalchemy_oso.flask import AuthorizedSQLAlchemy
+
+db = AuthorizedSQLAlchemy(
+    get_oso=lambda: current_app.oso,
+    get_user=lambda: getattr(g, "current_user", None),
+    get_action=lambda: "read"
+)
 
 
 class Expense(db.Model):