simplify Kerberos authentication by removing JSON parsing and token validation steps

src/aare/gui/auth.py

@@ -1,4 +1,3 @@
-import json
 import subprocess
 import jwt
 
@@ -23,11 +22,7 @@ def auth(base_url: str | None, cert_path: str | None) -> str:
     cacert = f"{cert_path}"
     try:
         token_result = subprocess.run(
-            ['curl', '-s', '--cacert', cacert,
-             '--negotiate', '-u', ':',
-             '-X', 'POST', url,
-             '-d', 'username=&password=',
-             '-H', 'Content-Type: application/x-www-form-urlencoded'],
+            ['curl', '-s', '--cacert', cacert, '--negotiate', '-u', ':', url],
             capture_output=True,
             text=True,
             timeout=18.0,
@@ -60,21 +55,12 @@ def auth(base_url: str | None, cert_path: str | None) -> str:
             "Check Kerberos ticket is valid (kinit) and server is reachable."
         )
 
-    try:
-        response_json = json.loads(token_result.stdout)
-    except json.JSONDecodeError as e:
-        logger.error(f"Token response not JSON. stdout: {token_result.stdout[:500]}")
+    token = token_result.stdout.strip()
+    if not token:
+        logger.error(f"Empty token response. stderr: {token_result.stderr[:500]}")
         raise RuntimeError(
-            "Authentication failed (invalid server response). "
+            "Authentication failed (empty server response). "
             "The server may be starting up or misconfigured."
-        ) from e
-
-    token = response_json.get("access_token")
-    if not token or not isinstance(token, str):
-        logger.error(f"Missing access_token. Keys: {list(response_json.keys())}. Server response {response_json}")
-        raise RuntimeError(
-            "Authentication failed (missing token in server response). "
-            "The server may be starting up."
         )
 
     return token