fix: add logging to auth_callback for better debugging of OIDC token exchange

backend/app/main.py

@@ -1,3 +1,4 @@
+import logging
 import os
 from typing import AsyncGenerator
 
@@ -20,6 +21,9 @@ app = FastAPI(
     version="0.1.0",
 )
 
+logging.basicConfig(level=logging.DEBUG)
+logger = logging.getLogger(__name__)
+
 app.add_middleware(
     CORSMiddleware,
     allow_origins=["*"],
@@ -88,14 +92,25 @@ async def auth_callback(payload: AuthCallbackRequest):
         data["client_id"] = settings.oidc_client_id
 
     async with httpx.AsyncClient(timeout=15.0) as client:
+        logger.debug("Token endpoint: %s", token_endpoint)
+        logger.debug("Token request data: %s", data)
+        logger.debug("Using auth: %s", "basic" if auth is not None else "none")
+
         response = await client.post(token_endpoint, data=data, headers={"Accept": "application/json"}, auth=auth)
+        logger.debug("Token response status: %s", response.status_code)
+        logger.debug("Token response headers: %s", response.headers)
+        logger.debug("Token response text: %s", response.text)
 
         # Some providers only accept client authentication via POST body
         if response.status_code != 200 and auth is not None:
             data_with_secret = dict(data)
             data_with_secret["client_id"] = settings.oidc_client_id
             data_with_secret["client_secret"] = settings.oidc_client_secret
+            logger.debug("Retrying with client_secret_post: %s", data_with_secret)
             response = await client.post(token_endpoint, data=data_with_secret, headers={"Accept": "application/json"})
+            logger.debug("Token response status (fallback): %s", response.status_code)
+            logger.debug("Token response headers (fallback): %s", response.headers)
+            logger.debug("Token response text (fallback): %s", response.text)
 
     if response.status_code != 200:
         raise HTTPException(status_code=400, detail=f"OIDC token exchange failed: {response.text}")