Add rest-api example (#889)

examples/rest-api/services.py

@@ -0,0 +1,26 @@
+from sqlalchemy.orm import Session
+
+from models import AppModel
+
+
+def get_app(db: Session, app_id: str):
+    return db.query(AppModel).filter(AppModel.app_id == app_id).first()
+
+
+def get_apps(db: Session, skip: int = 0, limit: int = 100):
+    return db.query(AppModel).offset(skip).limit(limit).all()
+
+
+def save_app(db: Session, app_id: str, config: str):
+    db_app = AppModel(app_id=app_id, config=config)
+    db.add(db_app)
+    db.commit()
+    db.refresh(db_app)
+    return db_app
+
+
+def remove_app(db: Session, app_id: str):
+    db_app = db.query(AppModel).filter(AppModel.app_id == app_id).first()
+    db.delete(db_app)
+    db.commit()
+    return db_app