backend/src/overpass/overpass.py

@@ -25,8 +25,9 @@ class Overpass :
         self.caching_strategy = CachingStrategy.use(caching_strategy, cache_dir=cache_dir)
 
 
+    @classmethod
     def build_query(self, area: tuple, osm_types: osm_types,
-                    selector: str, conditions=[], out='center'):
+                    selector: str, conditions=[], out='center') -> str:
         """
         Constructs a query string for the Overpass API to retrieve OpenStreetMap (OSM) data.
 
@@ -83,7 +84,7 @@ class Overpass :
         return query
 
 
-    def send_query(self, query: str) -> dict:
+    def send_query(self, query: str) -> ET:
         """
         Sends the Overpass QL query to the Overpass API and returns the parsed JSON response.
 
@@ -124,3 +125,47 @@ class Overpass :
 
         except urllib.error.URLError as e:
             raise ConnectionError(f"Error connecting to Overpass API: {e}") from e
+
+
+def get_base_info(elem: ET.Element, osm_type: osm_types, with_name=False) :
+    """
+    Extracts base information (coordinates, OSM ID, and optionally a name) from an OSM element.
+
+    This function retrieves the latitude and longitude coordinates, OSM ID, and optionally the name
+    of a given OpenStreetMap (OSM) element. It handles different OSM types (e.g., 'node', 'way') by
+    extracting coordinates either directly or from a center tag, depending on the element type.
+
+    Args:
+        elem (ET.Element): The XML element representing the OSM entity.
+        osm_type (str): The type of the OSM entity (e.g., 'node', 'way'). If 'node', the coordinates
+                        are extracted directly from the element; otherwise, from the 'center' tag.
+        with_name (bool): Whether to extract and return the name of the element. If True, it attempts
+                          to find the 'name' tag within the element and return its value. Defaults to False.
+
+    Returns:
+        tuple: A tuple containing:
+            - osm_id (str): The OSM ID of the element.
+            - coords (tuple): A tuple of (latitude, longitude) coordinates.
+            - name (str, optional): The name of the element if `with_name` is True; otherwise, not included.
+    """
+    # 1. extract coordinates
+    if osm_type != 'node' :
+        center = elem.find('center')
+        lat = float(center.get('lat'))
+        lon = float(center.get('lon'))
+
+    else :
+        lat = float(elem.get('lat'))
+        lon = float(elem.get('lon'))
+
+    coords = tuple((lat, lon))
+
+    # 2. Extract OSM id
+    osm_id = elem.get('id')
+
+    # 3. Extract name if specified and return
+    if with_name :
+        name = elem.find("tag[@k='name']").get('v') if elem.find("tag[@k='name']") is not None else None
+        return osm_id, coords, name
+    else :
+        return osm_id, coords

backend/src/utils/cluster_manager.py

@@ -6,7 +6,7 @@ import numpy as np
 from sklearn.cluster import DBSCAN
 from pydantic import BaseModel
 
-from ..overpass.overpass import Overpass
+from ..overpass.overpass import Overpass, get_base_info
 from ..structs.landmark import Landmark
 from .get_time_distance import get_distance
 from ..constants import OSM_CACHE_DIR
@@ -117,16 +117,10 @@ class ClusterManager:
             for osm_type in osm_types :
                 for elem in result.findall(osm_type):
                     
-                    if osm_type != 'node' :
-                        center = elem.find('center')
-                        lat = float(center.get('lat'))
-                        lon = float(center.get('lon'))
-                        points.append(tuple((lat, lon)))
-
-                    else :
-                        lat = float(elem.get('lat'))
-                        lon = float(elem.get('lon'))
-                        points.append(tuple((lat, lon)))
+                    # Get coordinates and append them to the points list
+                    _, coords = get_base_info(elem, osm_type)
+                    if coords is not None :
+                        points.append(coords)
 
             if points :
                 self.all_points = np.array(points)
@@ -263,24 +257,10 @@ class ClusterManager:
 
             for osm_type in osm_types :
                 for elem in result.findall(osm_type):
-                    name = elem.find("tag[@k='name']").get('v') if elem.find("tag[@k='name']") is not None else None
-                    center = elem.find('center')
 
-                    # Extract the center latitude and longitude if available.
-                    if name is None :
-                        continue
+                    id, coords, name = get_base_info(elem, osm_type, with_name=True)
 
-                    if osm_type != 'node' :
-                        lat = float(center.get('lat'))
-                        lon = float(center.get('lon'))
-
-                    else :
-                        lat = float(elem.get('lat'))
-                        lon = float(elem.get('lon'))
-
-                    coords = tuple((lat, lon))
-
-                    if coords is None :
+                    if name is None or coords is None :
                         continue
 
                     d = get_distance(cluster.centroid, coords)
@@ -288,7 +268,7 @@ class ClusterManager:
                         min_dist = d
                         new_name = name
                         osm_type = osm_type     # Add type: 'way' or 'relation'
-                        osm_id = elem.get('id')     # Add OSM id
+                        osm_id = id             # Add OSM id
 
         return Landmark(
             name=new_name,

backend/src/utils/landmarks_manager.py

@@ -8,7 +8,7 @@ from ..structs.preferences import Preferences
 from ..structs.landmark import Landmark
 from .take_most_important import take_most_important
 from .cluster_manager import ClusterManager
-from ..overpass.overpass import Overpass
+from ..overpass.overpass import Overpass, get_base_info
 
 from ..constants import AMENITY_SELECTORS_PATH, LANDMARK_PARAMETERS_PATH, OPTIMIZER_PARAMETERS_PATH, OSM_CACHE_DIR
 
@@ -239,28 +239,19 @@ class LandmarkManager:
         landmarks = []
         for osm_type in ['node', 'way', 'relation'] :
             for elem in root.findall(osm_type):
-                name = elem.find("tag[@k='name']").get('v') if elem.find("tag[@k='name']") is not None else None
-                tags = elem.findall('tag')
 
-                if osm_type != 'node' :
-                    center = elem.find('center')
-                    lat = float(center.get('lat'))
-                    lon = float(center.get('lon'))
-                    coords = tuple((lat, lon))
-
-                else :
-                    lat = float(elem.get('lat'))
-                    lon = float(elem.get('lon'))
-                    coords = tuple((lat, lon))
+                id, coords, name = get_base_info(elem, osm_type, with_name=True)
 
                 if name is None or coords is None :
                     continue
 
+                tags = elem.findall('tag')
+
                 # Convert this to Landmark object
                 landmark = Landmark(name=name,
                                     type=landmarktype,
                                     location=coords,
-                                    osm_id=elem.get('id'),
+                                    osm_id=id,
                                     osm_type=osm_type,
                                     attractiveness=0,
                                     n_tags=len(tags))

backend/src/utils/toilets_manager.py

@@ -2,7 +2,7 @@
 import logging
 import xml.etree.ElementTree as ET
 
-from ..overpass.overpass import Overpass
+from ..overpass.overpass import Overpass, get_base_info
 from ..structs.landmark import Toilets
 from ..constants import OSM_CACHE_DIR
 
@@ -98,23 +98,12 @@ class ToiletsManager:
         toilets_list = []
         for osm_type in ['node', 'way', 'relation'] :
             for elem in root.findall(osm_type):
-                center = elem.find('center')
-
-                # Extract the center latitude and longitude if available.
-                if osm_type != 'node' :
-                    lat = float(center.get('lat'))
-                    lon = float(center.get('lon'))
-                    location = tuple((lat, lon))
-
-                else :
-                    lat = float(elem.get('lat'))
-                    lon = float(elem.get('lon'))
-                    location = tuple((lat, lon))
-
-                if location is None :
+                # Get coordinates and append them to the points list
+                _, coords = get_base_info(elem, osm_type)
+                if coords is None :
                     continue
 
-                toilets = Toilets(location=location)
+                toilets = Toilets(location=coords)
 
                 # Extract tags as a dictionary
                 tags = {tag.get('k'): tag.get('v') for tag in elem.findall('tag')}