fix: [wifi_geolocation_kml] declare the gx namespace on the KML root element

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>

Author: elhoim

src/sysdiagnose/analysers/wifi_geolocation_kml.py

@@ -25,7 +25,15 @@ def execute(self) -> str:
     @staticmethod
     def generate_kml_from_known_networks_json(json_data: dict) -> str:
         """Generates KML XML string from known networks JSON data."""
-        kml = ET.Element("kml", xmlns="http://www.opengis.net/kml/2.2")
+        # the gx: prefix is used below (gx:Tour, gx:Playlist, gx:FlyTo, ...), so its namespace
+        # has to be declared on the root element or the document is not namespace-well-formed
+        kml = ET.Element(
+            "kml",
+            {
+                "xmlns": "http://www.opengis.net/kml/2.2",
+                "xmlns:gx": "http://www.google.com/kml/ext/2.2",
+            },
+        )
         document = ET.SubElement(kml, "Document")
 
         # Add tour elements

tests/test_analysers_wifi_geolocation_kml.py

@@ -1,5 +1,6 @@
 import os
 import unittest
+import xml.etree.ElementTree as ET
 
 from sysdiagnose.analysers.wifi_geolocation_kml import WifiGeolocationKmlAnalyser
 from tests import SysdiagnoseTestCase
@@ -20,6 +21,23 @@ def test_analyse_wifi_geolocation_kml(self):
                 self.assert_result_summary_consistent(a, a.get_result())
                 # FIXME check for something else within the file...
 
+    def test_generated_kml_is_namespace_well_formed(self):
+        """The gx: prefix must be declared, otherwise no conforming XML parser can read the file."""
+        kml = WifiGeolocationKmlAnalyser.generate_kml_from_known_networks_json(
+            {
+                "net1": {
+                    "SSID": "test-ssid",
+                    "AddedAt": "2023-05-24T13:29:15Z",
+                    "Latitude": 1.0,
+                    "Longitude": 2.0,
+                }
+            }
+        )
+        # on main this raises ParseError: unbound prefix
+        root = ET.fromstring(kml)
+        self.assertEqual("{http://www.opengis.net/kml/2.2}kml", root.tag)
+        self.assertIn("http://www.google.com/kml/ext/2.2", kml)
+
 
 if __name__ == "__main__":
     unittest.main()