Improve and use LibreNMS validation method

gso/services/librenms_client.py

@@ -91,22 +91,26 @@ class LibreNMSClient:
 
         return device.json()
 
-    def validate_device(self, fqdn: str) -> list[str]:
+    def validate_device(self, fqdn: str) -> str | None:
         """Validate a device in LibreNMS by fetching the record match the queried :term:`FQDN` against its hostname.
 
         :param str fqdn: The :term:`FQDN` of the host that is validated.
         :return list[str]: A list of errors, if empty the device is successfully validated.
         """
-        errors = []
+        error = None
         try:
             device = self.get_device(fqdn)
+            received_hostname = device["devices"][0]["hostname"]
 
-            if device["devices"][0]["hostname"] != fqdn:
-                errors.append("Device hostname in LibreNMS does not match FQDN.")
+            if received_hostname != fqdn:
+                error = (
+                    f"Device hostname in LibreNMS does not match FQDN.\n"
+                    f"Expected '{fqdn}' but got '{received_hostname}'."
+                )
         except HTTPError as e:
             if e.response.status_code == HTTPStatus.NOT_FOUND:
-                errors.append("Device does not exist in LibreNMS.")
+                error = "Device does not exist in LibreNMS."
             else:
                 raise
 
-        return errors
+        return error

gso/workflows/router/validate_router.py

@@ -54,7 +54,9 @@ def check_librenms_entry_exists(subscription: Router) -> None:
     Raises an HTTP error 404 when the device is not present in LibreNMS.
     """
     client = LibreNMSClient()
-    client.get_device(subscription.router.router_fqdn)
+    errors = client.validate_device(subscription.router.router_fqdn)
+    if errors:
+        raise ProcessFailureError(message="LibreNMS configuration error", details=errors)
 
 
 @step("Check base config for drift")

test/services/test_librenms_client.py

@@ -447,15 +447,13 @@ def test_validate_device_success(mock_get_device_success):
 
 def test_validate_device_non_existing(mock_get_device_not_found):
     client = LibreNMSClient()
-    errors = client.validate_device("localhost")
+    error = client.validate_device("localhost")
 
-    assert len(errors) == 1
-    assert errors[0] == "Device does not exist in LibreNMS."
+    assert error == "Device does not exist in LibreNMS."
 
 
 def test_validate_device_misconfigured(mock_get_device_misconfigured):
     client = LibreNMSClient()
-    errors = client.validate_device("localhost")
+    error = client.validate_device("localhost")
 
-    assert len(errors) == 1
-    assert errors[0] == "Device hostname in LibreNMS does not match FQDN."
+    assert error == "Device hostname in LibreNMS does not match FQDN.\nExpected 'localhost' but got '127.0.0.1'."

test/workflows/router/test_validate_router.py

@@ -16,9 +16,9 @@ from test.workflows import (
 @patch("gso.services.infoblox.find_host_by_fqdn")
 @patch("gso.services.lso_client.execute_playbook")
 @patch("gso.services.netbox_client.NetboxClient.get_device_by_name")
-@patch("gso.services.librenms_client.LibreNMSClient.get_device")
+@patch("gso.services.librenms_client.LibreNMSClient.validate_device")
 def test_validate_nokia_router_success(
-    mock_get_librenms_device,
+    mock_validate_librenms_device,
     mock_get_device_by_name,
     mock_execute_playbook,
     mock_find_host_by_fqdn,
@@ -27,6 +27,7 @@ def test_validate_nokia_router_success(
     data_config_filename,
     geant_partner,
 ):
+    mock_validate_librenms_device.return_value = None
     #  Run workflow
     subscription_id = nokia_router_subscription_factory()
     mock_fqdn = Router.from_subscription(subscription_id).router.router_fqdn
@@ -65,7 +66,7 @@ def test_validate_nokia_router_success(
     assert mock_execute_playbook.call_count == 2
     assert mock_find_host_by_fqdn.call_count == 1
     assert mock_get_device_by_name.call_count == 1
-    assert mock_get_librenms_device.call_count == 1
+    assert mock_validate_librenms_device.call_count == 1
     assert "ipam_warning" not in state