feat: add MyWhoosh token persistence

app/mywhoosh/tokenstore.py

@@ -0,0 +1,42 @@
+import json
+import os
+from pathlib import Path
+
+from app.mywhoosh.models import MyWhooshToken
+
+
+class MyWhooshTokenStore:
+    def __init__(self, path: Path) -> None:
+        self.path = path
+
+    def load(self) -> MyWhooshToken | None:
+        try:
+            raw = json.loads(self.path.read_text("utf-8"))
+        except FileNotFoundError:
+            return None
+        return MyWhooshToken(
+            access_token=raw["access_token"],
+            refresh_token=raw.get("refresh_token"),
+            whoosh_id=raw.get("whoosh_id"),
+        )
+
+    def save(self, token: MyWhooshToken) -> None:
+        self.path.parent.mkdir(parents=True, exist_ok=True, mode=0o700)
+        tmp = self.path.with_suffix(".tmp")
+        tmp.write_text(
+            json.dumps(
+                {
+                    "access_token": token.access_token,
+                    "refresh_token": token.refresh_token,
+                    "whoosh_id": token.whoosh_id,
+                },
+                indent=2,
+            ),
+            "utf-8",
+        )
+        os.chmod(tmp, 0o600)
+        tmp.replace(self.path)
+        os.chmod(self.path, 0o600)
+
+    def clear(self) -> None:
+        self.path.unlink(missing_ok=True)