backend/src/overpass/caching_strategy.py

@@ -1,5 +1,5 @@
 import os
-import xml.etree.ElementTree as ET
+import json
 import hashlib
 
 from ..constants import OSM_CACHE_DIR, OSM_TYPES
@@ -37,9 +37,9 @@ class CachingStrategyBase:
         """Clean up or close any resources used by the caching strategy."""
 
 
-class XMLCache(CachingStrategyBase):
+class JSONCache(CachingStrategyBase):
     """
-    A caching strategy that stores and retrieves data in XML format.
+    A caching strategy that stores and retrieves data in JSON format.
     """
     def __init__(self, cache_dir=OSM_CACHE_DIR):
         # Add the class name as a suffix to the directory
@@ -48,27 +48,28 @@ class XMLCache(CachingStrategyBase):
             os.makedirs(self._cache_dir)
 
     def _filename(self, key):
-        return os.path.join(self._cache_dir, f'{key}.xml')
+        return os.path.join(self._cache_dir, f'{key}.json')
 
     def get(self, key):
-        """Retrieve XML data from the cache and parse it as an ElementTree."""
+        """Retrieve JSON data from the cache and parse it as an ElementTree."""
         filename = self._filename(key)
         if os.path.exists(filename):
             try:
-                # Parse and return the cached XML data
+                # Open and parse the cached JSON data
-                tree = ET.parse(filename)
+                with open(filename, 'r', encoding='utf-8') as file:
-                return tree.getroot()  # Return the root element of the parsed XML
+                    data = json.load(file)
-            except ET.ParseError:
+                return data  # Return the parsed JSON data
-                return None
+            except json.JSONDecodeError as err:
+                return None  # Return None if parsing fails
         return None
 
     def set(self, key, value):
-        """Save the XML data as an ElementTree to the cache."""
+        """Save the JSON data as an ElementTree to the cache."""
         filename = self._filename(key)
-        tree = ET.ElementTree(value)  # value is expected to be an ElementTree root element
         try:
-            with open(filename, 'wb') as file:
+            # Write the JSON data to the cache file
-                tree.write(file, encoding='utf-8', xml_declaration=True)
+            with open(filename, 'w', encoding='utf-8') as file:
+                json.dump(value, file, ensure_ascii=False, indent=4)
         except IOError as e:
             raise IOError(f"Error writing to cache file: {filename} - {e}") from e
 
@@ -78,22 +79,21 @@ class XMLCache(CachingStrategyBase):
         hollow_key = f'hollow_{key}'
         filename = self._filename(hollow_key)
 
-        # Create the root element <cache>
+        # Create the hollow JSON structure
-        root = ET.Element("params")
+        hollow_data = {
-        # Add sub-elements with provided values
+            "key": key,
-        ET.SubElement(root, "key").text = key
+            "cell": list(cell),
-        ET.SubElement(root, "cell").text = f"({cell[0]}, {cell[1]})"
+            "osm_types": list(osm_types),
-        ET.SubElement(root, "osm_types").text = ','.join(osm_types)
+            "selector": selector,
-        ET.SubElement(root, "selector").text = selector
+            "conditions": conditions if conditions else "none",
-        ET.SubElement(root, "conditions").text = ','.join(conditions) if conditions else "none"
+            "out": out
-        ET.SubElement(root, "out").text = out
+        }
-
+        # Write the hollow data to the cache file
-        # Create an ElementTree object from the root
+        try:
-        tree = ET.ElementTree(root)
+            with open(filename, 'w', encoding='utf-8') as file:
-
+                json.dump(hollow_data, file, ensure_ascii=False, indent=4)
-        # Write the XML to the file
+        except IOError as e:
-        with open(filename, 'wb') as file:
+            raise IOError(f"Error writing hollow cache to file: {filename} - {e}") from e
-            tree.write(file, encoding='utf-8', xml_declaration=True)
 
     def close(self):
         """Cleanup method, if needed."""
@@ -103,13 +103,13 @@ class CachingStrategy:
     """
     A class to manage different caching strategies.
     """
-    __strategy = XMLCache()  # Default caching strategy
+    __strategy = JSONCache()  # Default caching strategy
     __strategies = {
-        'XML': XMLCache,
+        'JSON': JSONCache,
     }
 
     @classmethod
-    def use(cls, strategy_name='XML', **kwargs):
+    def use(cls, strategy_name='JSON', **kwargs):
         if cls.__strategy:
             cls.__strategy.close()
 

backend/src/overpass/overpass.py

@@ -3,7 +3,7 @@ import os
 import urllib
 import math
 import logging
-import xml.etree.ElementTree as ET
+import json
 
 from .caching_strategy import get_cache_key, CachingStrategy
 from ..constants import OSM_CACHE_DIR, OSM_TYPES
@@ -20,7 +20,7 @@ class Overpass :
     logger = logging.getLogger(__name__)
 
 
-    def __init__(self, caching_strategy: str = 'XML', cache_dir: str = OSM_CACHE_DIR) :
+    def __init__(self, caching_strategy: str = 'JSON', cache_dir: str = OSM_CACHE_DIR) :
         """
         Initialize the Overpass instance with the url, headers and caching strategy.
         """
@@ -30,9 +30,9 @@ class Overpass :
 
 
     def send_query(self, bbox: tuple, osm_types: OSM_TYPES,
-                    selector: str, conditions=[], out='center') -> ET:
+                    selector: str, conditions=[], out='center'):
         """
-        Sends the Overpass QL query to the Overpass API and returns the parsed XML response.
+        Sends the Overpass QL query to the Overpass API and returns the parsed json response.
 
         Args:
             bbox (tuple): Bounding box for the query.
@@ -42,7 +42,7 @@ class Overpass :
             out (str): Output format ('center', 'body', etc.). Defaults to 'center'.
 
         Returns:
-            ET.Element:    Parsed XML response from the Overpass API, or cached data if available.
+            dict:    Parsed json response from the Overpass API, or cached data if available.
         """
         # Determine which grid cells overlap with this bounding box.
         overlapping_cells = Overpass._get_overlapping_cells(bbox)
@@ -59,10 +59,10 @@ class Overpass :
         
         # Missing data: Make a query to Overpass API
         query_str = Overpass.build_query(bbox, osm_types, selector, conditions, out)
-        self.fetch_data_from_api(query_str)
+        return self.fetch_data_from_api(query_str)
 
 
-    def fetch_data_from_api(self, query_str: str, cache_key: str = None) -> ET.Element:
+    def fetch_data_from_api(self, query_str: str, cache_key: str = None) -> dict:
         """
         Fetch data from the Overpass API and update the cache.
 
@@ -72,33 +72,37 @@ class Overpass :
             hollow_cache_keys (list): Cache keys for missing data to be updated.
 
         Returns:
-            ET.Element: Combined cached and fetched data.
+            dict: Combined cached and fetched data.
         """
         try:
             data = urllib.parse.urlencode({'data': query_str}).encode('utf-8')
             request = urllib.request.Request(self.overpass_url, data=data, headers=self.headers)
 
             with urllib.request.urlopen(request) as response:
-                response_data = response.read().decode('utf-8')
+                response_data = response.read().decode('utf-8')  # Convert the HTTPResponse to a string
-                root = ET.fromstring(response_data)
+                data = json.loads(response_data)  # Load the JSON from the string
+                elements = data.get('elements', [])
 
                 if cache_key is not None :
-                    self.caching_strategy.set(cache_key, root)
+                    self.caching_strategy.set(cache_key, elements)
                     self.logger.debug(f'Cache set.')
                 else : 
                     self.logger.debug(f'Cache miss. Fetching data through Overpass\nQuery = {query_str}')
-                    return root
+                    return elements
 
         except urllib.error.URLError as e:
             self.logger.error(f"Error connecting to Overpass API: {e}")
             raise ConnectionError(f"Error connecting to Overpass API: {e}")
+        except Exception as exc :
+            raise Exception(f'An unexpected error occured: {str(exc)}') from exc
 
 
-    def fill_cache(self, xml_string: str) :
+
+    def fill_cache(self, json_data) :
         """
         Fill cache with data by using a hollow cache entry's information.
         """
-        query_str, cache_key = Overpass._build_query_from_hollow(xml_string)
+        query_str, cache_key = Overpass._build_query_from_hollow(json_data)
         self.fetch_data_from_api(query_str, cache_key)
 
 
@@ -133,7 +137,7 @@ class Overpass :
         if not isinstance(osm_types, list) :
             osm_types = [osm_types]
 
-        query = '('
+        query = '[out:json];('
 
         # convert the bbox to string.
         bbox_str = f"({','.join(map(str, bbox))})"
@@ -190,21 +194,21 @@ class Overpass :
 
 
     @staticmethod
-    def _build_query_from_hollow(xml_string):
+    def _build_query_from_hollow(json_data):
         """
         Build query string using information from a hollow cache entry.
         """
-        # Parse the XML string into an ElementTree object
+        # Parse the JSON string into a dictionary
-        root = ET.fromstring(xml_string)
+        data = json.loads(json_data)
         
-        # Extract values from the XML tree
+        # Extract values from the JSON object
-        key = root.find('key').text
+        key = data.get('key')
-        cell = tuple(map(float, root.find('cell').text.strip('()').split(',')))
+        cell = tuple(data.get('cell'))
         bbox = Overpass._get_bbox_from_grid_cell(cell[0], cell[1])
-        osm_types = root.find('osm_types').text.split(',')
+        osm_types = data.get('osm_types')
-        selector = root.find('selector').text
+        selector = data.get('selector')
-        conditions = root.find('conditions').text.split(',') if root.find('conditions').text != "none" else []
+        conditions = data.get('conditions') if data.get('conditions') != "none" else []
-        out = root.find('out').text
+        out = data.get('out')
 
         query_str = Overpass.build_query(bbox, osm_types, selector, conditions, out)
         
@@ -265,14 +269,14 @@ class Overpass :
         """
         Combines data from multiple cached responses into a single result.
         """
-        combined_data = ET.Element("osm")
+        combined_data = []
         for cached_data in cached_data_list:
             for element in cached_data:
                 combined_data.append(element)
         return combined_data
     
 
-def get_base_info(elem: ET.Element, osm_type: OSM_TYPES, with_name=False) :
+def get_base_info(elem: dict, osm_type: OSM_TYPES, with_name=False) :
     """
     Extracts base information (coordinates, OSM ID, and optionally a name) from an OSM element.
 
@@ -281,7 +285,7 @@ def get_base_info(elem: ET.Element, osm_type: OSM_TYPES, with_name=False) :
     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.
+        elem (dict): The JSON 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
@@ -295,7 +299,7 @@ def get_base_info(elem: ET.Element, osm_type: OSM_TYPES, with_name=False) :
     """
     # 1. extract coordinates
     if osm_type != 'node' :
-        center = elem.find('center')
+        center = elem.get('center')
         lat = float(center.get('lat'))
         lon = float(center.get('lon'))
 
@@ -310,7 +314,7 @@ def get_base_info(elem: ET.Element, osm_type: OSM_TYPES, with_name=False) :
 
     # 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
+        name = elem.get('tags', {}).get('name')
         return osm_id, coords, name
     else :
         return osm_id, coords
@@ -318,7 +322,7 @@ def get_base_info(elem: ET.Element, osm_type: OSM_TYPES, with_name=False) :
 
 def fill_cache():
 
-    overpass = Overpass(caching_strategy='XML', cache_dir=OSM_CACHE_DIR)
+    overpass = Overpass(caching_strategy='JSON', cache_dir=OSM_CACHE_DIR)
 
     with os.scandir(OSM_CACHE_DIR) as it:
         for entry in it:
@@ -326,10 +330,10 @@ def fill_cache():
                 
                 # Read the whole file content as a string
                 with open(entry.path, 'r') as f:
-                    xml_string = f.read()  
+                    json_data = f.read()  
 
                 # Fill the cache with the query and key
-                overpass.fill_cache(xml_string)
+                overpass.fill_cache(json_data)
 
                 # Now delete the file as the cache is filled
                 os.remove(entry.path)

backend/src/tests/test_main.py

@@ -28,7 +28,7 @@ def test_turckheim(client, request):    # pylint: disable=redefined-outer-name
         json={
             "preferences": {"sightseeing": {"type": "sightseeing", "score": 5},
             "nature": {"type": "nature", "score": 5},
-            "shopping": {"type": "shopping", "score": 5},
+            "shopping": {"type": "shopping", "score": 0},
             "max_time_minute": duration_minutes,
             "detour_tolerance_minute": 0},
             "start": [48.084588, 7.280405]
@@ -56,6 +56,7 @@ def test_turckheim(client, request):    # pylint: disable=redefined-outer-name
     assert duration_minutes*1.2 > result['total_time'], f"Trip too long: {result['total_time']} instead of {duration_minutes}"
     # assert 2!= 3
 
+
 def test_bellecour(client, request) :   # pylint: disable=redefined-outer-name
     """
     Test n°2 : Custom test in Lyon centre to ensure proper decision making in crowded area.
@@ -97,7 +98,6 @@ def test_bellecour(client, request) :   # pylint: disable=redefined-outer-name
     assert duration_minutes*0.8 < result['total_time'], f"Trip too short: {result['total_time']} instead of {duration_minutes}"
     assert duration_minutes*1.2 > result['total_time'], f"Trip too long: {result['total_time']} instead of {duration_minutes}"
 
-
 def test_cologne(client, request) :   # pylint: disable=redefined-outer-name
     """
     Test n°3 : Custom test in Cologne to ensure proper decision making in crowded area.

backend/src/utils/cluster_manager.py

@@ -9,7 +9,6 @@ from pydantic import BaseModel
 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
 from .utils import create_bbox
 
 
@@ -81,7 +80,7 @@ class ClusterManager:
             bbox: The bounding box coordinates (around:radius, center_lat, center_lon).
         """
         # Setup the caching in the Overpass class.
-        self.overpass = Overpass(caching_strategy='XML', cache_dir=OSM_CACHE_DIR)
+        self.overpass = Overpass()
 
         self.cluster_type = cluster_type
         if cluster_type == 'shopping' :
@@ -112,8 +111,8 @@ class ClusterManager:
 
         else :
             points = []
-            for osm_type in osm_types :
+            for elem in result:
-                for elem in result.findall(osm_type):
+                osm_type = elem.get('type')
                 
                 # Get coordinates and append them to the points list
                 _, coords = get_base_info(elem, osm_type)
@@ -249,8 +248,8 @@ class ClusterManager:
                 self.logger.error(f"Error fetching landmarks: {e}")
                 continue
 
-            for osm_type in osm_types :
+            for elem in result:
-                for elem in result.findall(osm_type):
+                osm_type = elem.get('type')
 
                 id, coords, name = get_base_info(elem, osm_type, with_name=True)
 

backend/src/utils/landmarks_manager.py

@@ -12,7 +12,7 @@ from .cluster_manager import ClusterManager
 from ..overpass.overpass import Overpass, get_base_info
 from .utils import create_bbox
 
-from ..constants import AMENITY_SELECTORS_PATH, LANDMARK_PARAMETERS_PATH, OPTIMIZER_PARAMETERS_PATH, OSM_CACHE_DIR
+from ..constants import AMENITY_SELECTORS_PATH, LANDMARK_PARAMETERS_PATH, OPTIMIZER_PARAMETERS_PATH
 
 
 class LandmarkManager:
@@ -54,7 +54,7 @@ class LandmarkManager:
             self.detour_factor = parameters['detour_factor']
 
         # Setup the caching in the Overpass class.
-        self.overpass = Overpass(caching_strategy='XML', cache_dir=OSM_CACHE_DIR)
+        self.overpass = Overpass()
 
         self.logger.info('LandmakManager successfully initialized.')
 
@@ -198,20 +198,20 @@ class LandmarkManager:
                     osm_types = osm_types,
                     selector = sel,
                     conditions = query_conditions,        # except for nature....
-                out = 'center'
+                    out = 'ids center tags'
                     )
             except Exception as e:
                 self.logger.error(f"Error fetching landmarks: {e}")
                 continue
 
-            return_list += self.xml_to_landmarks(result, landmarktype, preference_level)
+            return_list += self.json_to_landmarks(result, landmarktype, preference_level)
 
         self.logger.debug(f"Fetched {len(return_list)} landmarks of type {landmarktype} in {bbox}")
 
         return return_list
 
 
-    def xml_to_landmarks(self, root: ET.Element, landmarktype, preference_level) -> list[Landmark]:
+    def json_to_landmarks(self, elements: list, landmarktype, preference_level) -> list[Landmark]:
         """
         Parse the Overpass API result and extract landmarks.
 
@@ -221,25 +221,26 @@ class LandmarkManager:
         into Landmark objects.
 
         Args:
-        root (ET.Element): The root element of the XML response from Overpass API.
+        elements (list): The elements of json response from Overpass API.
         elem_type (str): The type of landmark (e.g., node, way, relation).
 
         Returns:
         list[Landmark]: A list of Landmark objects extracted from the XML data.
         """
-        if root is None :
+        print(f'in landmarks manager : {type(elements)}')
+        if elements is None :
             return []
 
         landmarks = []
-        for osm_type in ['node', 'way', 'relation'] :
+        for elem in elements:
-            for elem in root.findall(osm_type):
+            osm_type = elem.get('type')
 
             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')
+            tags = elem.get('tags')
 
             # Convert this to Landmark object
             landmark = Landmark(name=name,
@@ -250,10 +251,10 @@ class LandmarkManager:
                                 attractiveness=0,
                                 n_tags=len(tags))
 
+            # self.logger.debug('added landmark.')
+
             # Browse through tags to add information to landmark.
-                for tag in tags:
+            for key, value in tags.items():
-                    key = tag.get('k')
-                    value = tag.get('v')
 
                 # Skip this landmark if not suitable.
                 if key == 'building:part' and value == 'yes' :

backend/src/utils/toilets_manager.py

@@ -4,7 +4,6 @@ import xml.etree.ElementTree as ET
 
 from ..overpass.overpass import Overpass, get_base_info
 from ..structs.landmark import Toilets
-from ..constants import OSM_CACHE_DIR
 from .utils import create_bbox
 
 
@@ -42,7 +41,7 @@ class ToiletsManager:
         self.location = location
 
         # Setup the caching in the Overpass class.
-        self.overpass = Overpass(caching_strategy='XML', cache_dir=OSM_CACHE_DIR)
+        self.overpass = Overpass()
 
 
     def generate_toilet_list(self) -> list[Toilets] :
@@ -70,33 +69,33 @@ class ToiletsManager:
             self.logger.error(f"Error fetching landmarks: {e}")
             return None
 
-        toilets_list = self.xml_to_toilets(result)
+        toilets_list = self.to_toilets(result)
 
         return toilets_list
 
 
-    def xml_to_toilets(self, root: ET.Element) -> list[Toilets]:
+    def to_toilets(self, elements: list) -> list[Toilets]:
         """
         Parse the Overpass API result and extract landmarks.
 
-        This method processes the XML root element returned by the Overpass API and 
+        This method processes the JSON elements returned by the Overpass API and 
         extracts landmarks of types 'node', 'way', and 'relation'. It retrieves 
         relevant information such as name, coordinates, and tags, and converts them 
         into Landmark objects.
 
         Args:
-        root (ET.Element): The root element of the XML response from Overpass API.
+        list (osm elements): The root element of the JSON response from Overpass API.
         elem_type (str): The type of landmark (e.g., node, way, relation).
 
         Returns:
         list[Landmark]: A list of Landmark objects extracted from the XML data.
         """
-        if root is None :
+        if elements is None :
             return []
 
         toilets_list = []
-        for osm_type in ['node', 'way', 'relation'] :
+        for elem in elements:
-            for elem in root.findall(osm_type):
+            osm_type = elem.get('type')
             # Get coordinates and append them to the points list
             _, coords = get_base_info(elem, osm_type)
             if coords is None :
@@ -105,7 +104,7 @@ class ToiletsManager:
             toilets = Toilets(location=coords)
 
             # Extract tags as a dictionary
-                tags = {tag.get('k'): tag.get('v') for tag in elem.findall('tag')}
+            tags = elem.get('tags')
 
             if 'wheelchair' in tags.keys() and tags['wheelchair'] == 'yes':
                 toilets.wheelchair = True