feat: add automatic historical fetch on startup if DB is empty

src/exchanges/ls.py

@@ -8,20 +8,22 @@ class LSExchange(BaseExchange):
     def name(self) -> str:
         return "LS"
 
-    def fetch_latest_trades(self) -> List[Trade]:
-        # Today's trades endpoint
-        url = "https://www.ls-x.de/_rpc/json/.lstc/instrument/list/lstctradestoday"
+    def fetch_latest_trades(self, include_yesterday: bool = False) -> List[Trade]:
+        endpoints = ["https://www.ls-x.de/_rpc/json/.lstc/instrument/list/lstctradestoday"]
+        if include_yesterday:
+            endpoints.append("https://www.ls-x.de/_rpc/json/.lstc/instrument/list/lstctradesyesterday")
         
-        # We might need headers to mimic a browser or handle disclaimer
         headers = {
             'User-Agent': 'Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/120.0.0.0 Safari/537.36',
             'Accept': 'application/json',
             'Referer': 'https://www.ls-tc.de/'
         }
         
-        try:
-            response = requests.get(url, headers=headers)
-            response.raise_for_status()
+        all_trades = []
+        for url in endpoints:
+            try:
+                response = requests.get(url, headers=headers)
+                response.raise_for_status()
             
             import csv
             import io
@@ -42,7 +44,7 @@ class LSExchange(BaseExchange):
                     ts_str = time_str.replace('Z', '+00:00')
                     timestamp = datetime.fromisoformat(ts_str)
                     
-                    trades.append(Trade(
+                    all_trades.append(Trade(
                         exchange=self.name,
                         symbol=symbol,
                         isin=isin,
@@ -52,7 +54,6 @@ class LSExchange(BaseExchange):
                     ))
                 except Exception:
                     continue
-            return trades
-        except Exception as e:
-            print(f"Error fetching LS data: {e}")
-            return []
+            except Exception as e:
+                print(f"Error fetching LS data from {url}: {e}")
+        return all_trades