fix: server error when attmepting to access non-existant dataset

server/utils.py

@@ -1,5 +1,10 @@
 import datetime
+import pandas as pd
+
 from flask import request
+from flask_jwt_extended import get_jwt_identity
+from db.database import PostgresConnector
+from server.exceptions import NotAuthorisedException
 
 def parse_datetime_filter(value):
     if not value:
@@ -47,4 +52,13 @@ def get_request_filters() -> dict:
     if data_sources:
         filters["data_sources"] = data_sources
 
-    return filters
+    return filters
+
+def get_dataset_and_validate(dataset_id: int, db: PostgresConnector) -> pd.DataFrame:
+    current_user = get_jwt_identity()
+    dataset = db.get_dataset_info(dataset_id)
+
+    if dataset.get("user_id") != int(current_user):
+        raise NotAuthorisedException("This user is not authorised to access this dataset")
+    
+    return db.get_dataset_content(dataset_id)