Merge pull request #98 from NatLibFi/analytics_exporter_fix

Fix max_contribs calculation to handle None values

api/local_analytics_exporter.py

@@ -75,7 +75,9 @@ def export_excel(self, _db, start, end, locations=None, library=None):
         rows = [dict(row) for row in results]
 
         # Count how many contributor rows we need
-        max_contribs = max([0, *[len(row.get("contributors", [])) for row in rows]])
+        max_contribs = max(
+            [0, *[len(row.get("contributors", []) or []) for row in rows]]
+        )
 
         header = [
             "Tekijä (aakkostus)",
@@ -99,8 +101,7 @@ def export_excel(self, _db, start, end, locations=None, library=None):
             genres = row.get("genres")
             categories = ", ".join(genres) if genres else ""
 
-            contributors = row.get("contributors", [])
-
+            contributors = row.get("contributors") or []
             sheet.append(
                 [
                     # Tekijä (aakkostus)