🔀 Merge pull request #69 from davep/data-version-check

Add a local data version check

src/braindrop/app/data/local.py

@@ -5,7 +5,7 @@
 from datetime import datetime
 from json import dumps, loads
 from pathlib import Path
-from typing import Any, Callable
+from typing import Any, Callable, Final
 
 ##############################################################################
 # pytz imports.
@@ -43,6 +43,9 @@ def local_data_file() -> Path:
 class LocalData:
     """Holds and manages the local copy of the Raindrop data."""
 
+    VERSION: Final[int] = 0
+    """The version of the format of the local data."""
+
     def __init__(self, api: API) -> None:
         """Initialise the object.
 
@@ -63,12 +66,19 @@ def __init__(self, api: API) -> None:
         """An index of all of the Raindrops we know about."""
         self._last_downloaded: datetime | None = None
         """The time the data was last downloaded from the server."""
+        self._version: int | None = None
+        """The version of the format of the data."""
 
     @property
     def last_downloaded(self) -> datetime | None:
         """The time the data was downloaded, or `None` if not yet."""
         return self._last_downloaded
 
+    @property
+    def outdated_format(self) -> bool:
+        """Is the format of the local data outdated?"""
+        return self._version is None or self._version < self.VERSION
+
     @property
     def user(self) -> User | None:
         """The user that the data relates to."""
@@ -252,6 +262,7 @@ def _local_json(self) -> dict[str, Any]:
             "last_downloaded": None
             if self._last_downloaded is None
             else self._last_downloaded.isoformat(),
+            "version": self.VERSION,
             "user": None if self._user is None else self._user.raw,
             "all": [raindrop.raw for raindrop in self._all],
             "trash": [raindrop.raw for raindrop in self._trash],
@@ -277,6 +288,11 @@ def load(self) -> Self:
         """
         if local_data_file().exists():
             data = loads(local_data_file().read_text(encoding="utf-8"))
+            self._version = data.get("version")
+            if self.outdated_format:
+                # The version is unknown, or older than we're expecting, so
+                # let's pretend it doesn't exist.
+                return self
             self._last_downloaded = get_time(data, "last_downloaded")
             self._user = User.from_json(data.get("user", {}))
             self._all.set_to(

src/braindrop/app/screens/main.py

@@ -241,7 +241,9 @@ async def maybe_redownload(self) -> None:
             )
             return
 
-        if self._data.last_downloaded is None:
+        if self._data.outdated_format:
+            self.notify("Local file format has changed; rebuilding from the server.")
+        elif self._data.last_downloaded is None:
             self.notify("No local data found; checking in with the server.")
         elif (
             self._user.last_update is not None