squashme: address comments

renku_notebooks/api/classes/image.py

@@ -61,7 +61,16 @@ def _get_docker_token(self, image: "Image") -> Optional[str]:
             creds = base64.urlsafe_b64encode(f"oauth2:{self.oauth2_token}".encode()).decode()
             headers["Authorization"] = f"Basic {creds}"
         token_req = requests.get(realm, params=params, headers=headers)
-        return str(token_req.json().get("token"))
+        if token_req.status_code != 200:
+            return None
+        try:
+            res_dict = token_req.json()
+        except requests.JSONDecodeError:
+            return None
+        token = res_dict.get("token")
+        if not token:
+            return None
+        return str(token)
 
     def get_image_manifest(
         self,
@@ -113,8 +122,8 @@ def platform_matches(manifest: dict[str, Any]) -> bool:
             if res.status_code != 200:
                 headers["Accept"] = ManifestTypes.oci_v1_manifest.value
                 res = requests.get(image_digest_url, headers=headers)
-            if res.status_code != 200:
-                return None
+                if res.status_code != 200:
+                    return None
 
         if res.headers.get("Content-Type") not in [
             ManifestTypes.docker_v2.value,