adding last seen date into the listing

crawler/data_access.py

@@ -59,6 +59,16 @@ class Listing:
     def path_floorplan_file(self, order, name) -> pathlib.Path:
         self.path_floorplan_folder().mkdir(parents=True, exist_ok=True)
         return self.path_floorplan_folder() / f"{order}_{name}"
+    
+    def path_last_seen_listing(self) -> pathlib.Path:
+        return self.path_listing() / "last_seen.json"
+    
+    def dump_listing(self, d: dict):
+        with open(self.path_listing_json(), "w") as f:
+            json.dump(d, f)
+        with open(self.path_last_seen_listing(), "w") as f:
+            dt = datetime.datetime.now().isoformat()
+            json.dump(dt, f)
 
     def list_floorplans(self):
         images = list(self.path_floorplan_folder().glob("*"))
@@ -203,6 +213,15 @@ class Listing:
         ds = datetime.datetime.fromtimestamp(ts)
         return (now - ds).days
 
+    @property
+    def last_seen(self) -> datetime.datetime:
+        if not self.path_last_seen_listing().exists():
+            return None
+        
+        with open(self.path_last_seen_listing(), 'r') as f:
+            datetime_str = json.load(f)
+            return datetime.fromisoformat(datetime_str)
+
     @property
     def serviceCharge(self) -> float:
         ds = self.detailobject["property"].get("tenureInfo", {}).get("content", [])
@@ -255,6 +274,7 @@ class Listing:
             "tenure_type": self.tenure_type,
             "updated_days": self.updateDaysAgo,
             "status": self.status,
+            "last_seen": self.last_seen,
         }