Fix: Add mock fallback for DOAJ API 403 Forbidden error

app/services/doaj_service.py

@@ -68,8 +68,22 @@ class DOAJService:
             return results
         except Exception as e:
             logger.error(f"DOAJ search error: {e}")
+            if "403" in str(e) or "401" in str(e):
+                logger.warning("DOAJ API returned 403 Forbidden. Using mock data for hackathon demo.")
+                return [
+                    {
+                        "id": f"doaj_mock_{uuid.uuid4().hex[:8]}",
+                        "title": f"Open Access Analysis on {query}",
+                        "authors": ["Dr. Open Access", "A. Researcher"],
+                        "summary": f"This is a mocked DOAJ article discussing {query}. The DOAJ API is currently blocking requests with 403 Forbidden, so this mock data is provided for the hackathon demonstration.",
+                        "url": "https://doaj.org",
+                        "has_pdf": False,
+                        "categories": ["Science", "Open Access"],
+                        "publication_date": "2024",
+                        "source": "DOAJ"
+                    }
+                ]
             return []
-
     def download_paper(self, paper_url: str, paper_id: str) -> str:
         """
         Downloads a paper from a direct URL.