Fix some IDE warnings, mostly around type safety on the Python side

solarconditionsproviders/giroionosonde.py

@@ -28,7 +28,8 @@ class GIROIonosonde(SolarConditionsProvider):
         self._thread = None
         self._stop_event = Event()
 
-    def _load_stations(self):
+    @staticmethod
+    def _load_stations():
         stations = []
         with open(STATIONS_INDEX, newline='') as f:
             for row in csv.reader(f):

solarconditionsproviders/hamqsl.py

@@ -32,6 +32,9 @@ class HamQSL(HTTPSolarConditionsProvider):
         # Some error checking functions in case the data is janky.
 
         def text(tag, default=None):
+            if sd is None:
+                logging.warning("HamQSL solar conditions API returned unexpected XML structure")
+                return default
             el = sd.find(tag)
             return el.text.strip() if el is not None and el.text else default
 
@@ -104,7 +107,7 @@ class HamQSL(HTTPSolarConditionsProvider):
             "geomag_noise": text("signalnoise"),
             "hf_conditions": hf_conditions,
             "vhf_conditions": {
-                "vhf_aurora_northern_hemi": vhf_map.get(("vhf-aurora", "northern_hemi")).title().replace("Lat Aur", "Latitude"),
+                "vhf_aurora_northern_hemi": (vhf_map.get(("vhf-aurora", "northern_hemi")) or "").title().replace("Lat Aur", "Latitude") or None,
                 "es_2m_europe": vhf_map.get(("E-Skip", "europe")),
                 "es_4m_europe": vhf_map.get(("E-Skip", "europe_4m")),
                 "es_6m_europe": vhf_map.get(("E-Skip", "europe_6m")),

solarconditionsproviders/ionosonde_utils.py

@@ -3,8 +3,8 @@ from core.constants import BANDS
 HF_BANDS = [b for b in BANDS if b.is_ham_hf]
 
 
-def _latest(d):
-    return d[max(d.keys())] if d else None
+def _latest(d) -> float | None:
+    return float(d[max(d.keys())]) if d else None
 
 
 def compute_band_states(fof2_dict, muf_dict, luf_dict):

solarconditionsproviders/solar_conditions_provider.py

@@ -10,6 +10,7 @@ class SolarConditionsProvider:
     def __init__(self, provider_config):
         """Constructor"""
 
+        self._solar_conditions_cache = None
         self.name = provider_config["name"]
         self.enabled = provider_config["enabled"]
         self.last_update_time = datetime.min.replace(tzinfo=pytz.UTC)