Add tag verification.

map_machine/osm/osm_reader.py

@@ -107,6 +107,20 @@ class Tagged:
 
         return None
 
+    def verify(self) -> bool:
+        """Check key and value types."""
+        is_well_formed: bool = True
+
+        for value, key in self.tags.items():
+            if not isinstance(key, str):
+                logging.warning(f"Not string key {key}.")
+                is_well_formed = False
+            if not isinstance(value, str):
+                logging.warning(f"Not string value {value}.")
+                is_well_formed = False
+
+        return is_well_formed
+
 
 @dataclass
 class OSMNode(Tagged):

map_machine/scheme.py

@@ -14,7 +14,7 @@ from colour import Color
 
 from map_machine.feature.direction import DirectionSet
 from map_machine.map_configuration import MapConfiguration, LabelMode
-from map_machine.osm.osm_reader import Tags
+from map_machine.osm.osm_reader import Tagged, Tags
 from map_machine.pictogram.icon import (
     DEFAULT_COLOR,
     DEFAULT_SHAPE_ID,
@@ -102,7 +102,7 @@ def match_location(restrictions: dict[str, str], country: str) -> bool:
     return True
 
 
-class Matcher:
+class Matcher(Tagged):
     """Tag matching."""
 
     def __init__(
@@ -126,6 +126,8 @@ class Matcher:
         if "location_restrictions" in structure:
             self.location_restrictions = structure["location_restrictions"]
 
+        self.verify()
+
     def check_zoom_level(self, zoom_level: float) -> bool:
         """Check whether zoom level is matching."""
         return (