fix(proxmox): handle AttributeError when Qemu Agent is not available

- Add AttributeError to existing exception handling in _get_vm_hostname()
- Fall back to using vm_name when Qemu Agent is unavailable
- Add test case for AttributeError scenario
- Maintain existing logging behavior for debugging

Fixes #21300

Signed-off-by: puretension <rlrlfhtm5@gmail.com>

Author: puretension

proxmox/datadog_checks/proxmox/check.py

@@ -153,7 +153,8 @@ def _get_vm_hostname(self, vm_id, vm_name, node):
                 self.config.proxmox_server,
                 e,
             )
-            hostname_json = {}
+            hostname = vm_name
+            return hostname
         hostname = hostname_json.get("data", {}).get("result", {}).get("host-name", vm_name)
         return hostname
 

proxmox/tests/test_unit.py

@@ -299,6 +299,36 @@ def test_get_hostname_error(dd_run_check, aggregator, instance, caplog):
     )
 
 
+class AttributeErrorResponse:
+    """Mock response that raises AttributeError when json() is called."""
+
+    def json(self):
+        raise AttributeError("Qemu Agent not available")
+
+
+@pytest.mark.parametrize(
+    ('mock_http_get'),
+    [
+        pytest.param(
+            {'http_error': {'/api2/json/nodes/ip-122-82-3-112/qemu/100/agent/get-host-name': AttributeErrorResponse()}},
+            id='attribute_error',
+        ),
+    ],
+    indirect=['mock_http_get'],
+)
+@pytest.mark.usefixtures('mock_http_get')
+def test_get_hostname_attribute_error(dd_run_check, aggregator, instance, caplog):
+    """Test that AttributeError is handled when Qemu Agent is not available."""
+    check = ProxmoxCheck('proxmox', {}, [instance])
+    check.check_id = 'test:123'
+    caplog.set_level(logging.INFO)
+
+    dd_run_check(check)
+
+    aggregator.assert_metric("proxmox.vm.up", 1, tags=[], hostname="VM 100")
+    assert "Failed to get hostname for vm 100 on node ip-122-82-3-112" in caplog.text
+
+
 @pytest.mark.usefixtures('mock_http_get')
 def test_external_tags(dd_run_check, aggregator, instance, datadog_agent):
     check = ProxmoxCheck('proxmox', {}, [instance])