fix:add debugging endpoint for auth issues

.beans/nuzlocke-tracker-snft--support-es256-ecc-p-256-jwt-keys-in-backend-auth.md

@@ -5,9 +5,11 @@ status: completed
 type: bug
 priority: normal
 created_at: 2026-03-22T10:51:30Z
-updated_at: 2026-03-22T10:52:46Z
+updated_at: 2026-03-22T10:59:46Z
 ---
 
 Backend JWKS verification only accepts RS256 algorithm, but Supabase JWT key was switched to ECC P-256 (ES256). This causes 401 errors on all authenticated requests. Fix: accept both RS256 and ES256 in the algorithms list, and update tests accordingly.
 
 ## Summary of Changes\n\nAdded ES256 to the accepted JWT algorithms in `_verify_jwt()` so ECC P-256 keys from Supabase are verified correctly alongside RSA keys. Added corresponding test with EC key fixtures.
+
+Deployed to production via PR #86 merge on 2026-03-22.

backend/src/app/api/health.py

@@ -1,6 +1,10 @@
-from fastapi import APIRouter
+import urllib.request
+
+from fastapi import APIRouter, Request
 from sqlalchemy import text
 
+from app.core.auth import _build_jwks_url, _extract_token, _get_jwks_client
+from app.core.config import settings
 from app.core.database import async_session
 
 router = APIRouter(tags=["health"])
@@ -23,3 +27,45 @@ async def health_check():
 async def root():
     """Root endpoint."""
     return {"message": "Nuzlocke Tracker API", "docs": "/docs"}
+
+
+@router.get("/auth-debug")
+async def auth_debug(request: Request):
+    """Temporary diagnostic endpoint for auth debugging."""
+    result: dict = {}
+
+    # Config
+    result["supabase_url"] = settings.supabase_url
+    result["has_jwt_secret"] = bool(settings.supabase_jwt_secret)
+    result["jwks_url"] = (
+        _build_jwks_url(settings.supabase_url) if settings.supabase_url else None
+    )
+
+    # JWKS fetch
+    jwks_url = result["jwks_url"]
+    if jwks_url:
+        try:
+            with urllib.request.urlopen(jwks_url, timeout=5) as resp:
+                result["jwks_status"] = resp.status
+                result["jwks_body"] = resp.read().decode()
+        except Exception as e:
+            result["jwks_fetch_error"] = str(e)
+
+    # JWKS client
+    client = _get_jwks_client()
+    result["jwks_client_exists"] = client is not None
+
+    # Token info (header only, no secrets)
+    token = _extract_token(request)
+    if token:
+        import jwt
+
+        try:
+            header = jwt.get_unverified_header(token)
+            result["token_header"] = header
+        except Exception as e:
+            result["token_header_error"] = str(e)
+    else:
+        result["token"] = "not provided"
+
+    return result

backend/src/app/core/auth.py

@@ -1,3 +1,4 @@
+import logging
 from dataclasses import dataclass
 from uuid import UUID
 
@@ -12,6 +13,7 @@ from app.core.database import get_session
 from app.models.nuzlocke_run import NuzlockeRun
 from app.models.user import User
 
+logger = logging.getLogger(__name__)
 _jwks_client: PyJWKClient | None = None
 
 
@@ -24,11 +26,21 @@ class AuthUser:
     role: str | None = None
 
 
+def _build_jwks_url(base_url: str) -> str:
+    """Build the JWKS URL, adding /auth/v1 prefix for Supabase Cloud."""
+    base = base_url.rstrip("/")
+    if "/auth/v1" in base:
+        return f"{base}/.well-known/jwks.json"
+    # Supabase Cloud URLs need the /auth/v1 prefix;
+    # local GoTrue serves JWKS at root but uses HS256 fallback anyway.
+    return f"{base}/auth/v1/.well-known/jwks.json"
+
+
 def _get_jwks_client() -> PyJWKClient | None:
     """Get or create a cached JWKS client."""
     global _jwks_client
     if _jwks_client is None and settings.supabase_url:
-        jwks_url = f"{settings.supabase_url.rstrip('/')}/.well-known/jwks.json"
+        jwks_url = _build_jwks_url(settings.supabase_url)
         _jwks_client = PyJWKClient(jwks_url, cache_jwk_set=True, lifespan=300)
     return _jwks_client
 
@@ -71,12 +83,14 @@ def _verify_jwt(token: str) -> dict | None:
                 algorithms=["RS256", "ES256"],
                 audience="authenticated",
             )
-        except jwt.InvalidTokenError:
+        except jwt.InvalidTokenError as e:
-            pass
+            logger.warning("JWKS JWT validation failed: %s", e)
-        except PyJWKClientError:
+        except PyJWKClientError as e:
-            pass
+            logger.warning("JWKS client error: %s", e)
-        except PyJWKSetError:
+        except PyJWKSetError as e:
-            pass
+            logger.warning("JWKS set error: %s", e)
+    else:
+        logger.warning("No JWKS client available (SUPABASE_URL not set?)")
     return _verify_jwt_hs256(token)