Fix gitbook connector issues

backend/onyx/connectors/gitbook/connector.py

@@ -229,16 +229,20 @@ def _fetch_all_pages(
 
         try:
             content = self.client.get(f"/spaces/{self.space_id}/content")
-            pages = content.get("pages", [])
-
+            pages: list[dict[str, Any]] = content.get("pages", [])
             current_batch: list[Document] = []
-            for page in pages:
-                updated_at = datetime.fromisoformat(page["updatedAt"])
 
+            while pages:
+                page = pages.pop(0)
+
+                updated_at_raw = page.get("updatedAt")
+                if updated_at_raw is None:
+                    # if updatedAt is not present, that means the page has never been edited
+                    continue
+
+                updated_at = datetime.fromisoformat(updated_at_raw)
                 if start and updated_at < start:
-                    if current_batch:
-                        yield current_batch
-                    return
+                    continue
                 if end and updated_at > end:
                     continue
 
@@ -250,6 +254,8 @@ def _fetch_all_pages(
                     yield current_batch
                     current_batch = []
 
+                pages.extend(page.get("pages", []))
+
             if current_batch:
                 yield current_batch