Store: fix for multithreading

locomotive/stores.py

@@ -92,26 +92,30 @@ class Stations:
     See https://github.com/trainline-eu/stations.
     """
 
-    conn: sqlite3.Connection
     path: Path
 
     def __init__(self, path: Optional[Path] = None) -> None:
-        if path is None:
-            path = self.default_path()
-        # TODO: Close DB ?
-        self.conn = sqlite3.connect(f"file:{path}?mode=ro", uri=True)
+        self.path = self.default_path()
+        if path:
+            self.path = path
+
+    def _conn(self) -> sqlite3.Connection:
+        return sqlite3.connect(f"file:{self.path}?mode=ro", uri=True)
 
     @classmethod
     def default_path(cls) -> Path:
         return Path(__file__).parent.joinpath("data", "stations.sqlite3")
 
     def count(self) -> int:
-        with contextlib.closing(self.conn.cursor()) as c:
+        with self._conn() as conn:
+            c = conn.cursor()
             c.execute("SELECT COUNT(*) FROM stations")
             return int(c.fetchone()[0])
 
     def find(self, query: str) -> Optional[Station]:
-        with contextlib.closing(self.conn.cursor()) as c:
+        with self._conn() as conn:
+            c = conn.cursor()
+
             # a) Try to find matching IDs
             c.execute("SELECT * FROM stations WHERE sncf_id LIKE ?", (query,))
             row = c.fetchone()