Always downgrade the database before sync

This prevents the missing collation unicase error on the client

src/ankisyncd/full_sync.py

@@ -1,13 +1,36 @@
 # -*- coding: utf-8 -*-
 
+import logging
 import os
 from sqlite3 import dbapi2 as sqlite
+import shutil
 import sys
+from webob.exc import HTTPBadRequest
 
-import anki.db
+from anki.db import DB
+from anki.collection import Collection
 
-class FullSyncManager:
-    def upload(self, col, data, session):
+logger = logging.getLogger("ankisyncd.media")
+logger.setLevel(1)
+
+class FullSyncManager(object):
+    def test_db(self, db: DB):
+        """
+        :param anki.db.DB db: the database uploaded from the client.
+        """
+        if db.scalar("pragma integrity_check") != "ok":
+            raise HTTPBadRequest(
+                "Integrity check failed for uploaded collection database file."
+            )
+
+    def upload(self, col: Collection, data: bytes, session) -> str:
+        """
+        Uploads a sqlite database from the client to the sync server.
+
+        :param anki.collection.Collectio col:
+        :param bytes data: The binary sqlite database from the client.
+        :param .sync_app.SyncUserSession session: The current session.
+        """
         # Verify integrity of the received database file before replacing our
         # existing db.
         temp_db_path = session.get_collection_path() + ".tmp"
@@ -15,10 +38,8 @@ class FullSyncManager:
             f.write(data)
 
         try:
-            with anki.db.DB(temp_db_path) as test_db:
-                if test_db.scalar("pragma integrity_check") != "ok":
-                    raise HTTPBadRequest("Integrity check failed for uploaded "
-                                         "collection database file.")
+            with DB(temp_db_path) as test_db:
+                self.test_db(test_db)
         except sqlite.Error as e:
             raise HTTPBadRequest("Uploaded collection database file is "
                                  "corrupt.")
@@ -26,7 +47,7 @@ class FullSyncManager:
         # Overwrite existing db.
         col.close()
         try:
-            os.replace(temp_db_path, session.get_collection_path())
+            shutil.copyfile(temp_db_path, session.get_collection_path())
         finally:
             col.reopen()
             # Reopen the media database
@@ -34,13 +55,27 @@ class FullSyncManager:
 
         return "OK"
 
+    def download(self, col: Collection, session) -> bytes:
+        """Download the binary database.
 
-    def download(self, col, session):
-        col.close()
+        Performs a downgrade to database schema 11 before sending the database
+        to the client.
+
+        :param anki.collection.Collection col:
+        :param .sync_app.SyncUserSession session:
+
+        :return bytes: the binary sqlite3 database
+        """
+        col.close(downgrade=True)
+        db_path = session.get_collection_path()
         try:
-            data = open(session.get_collection_path(), 'rb').read()
+            with open(db_path, 'rb') as tmp:
+                data = tmp.read()
         finally:
             col.reopen()
+            # Reopen the media database
+            col.media.connect()
+
         return data