fix: user-feedback-on-schema-mismatch (#1558)

* validate schema version on restore

* show user error on backup failure

frontend/pages/admin/backups.vue

@@ -5,7 +5,7 @@
       <!-- Delete Dialog -->
       <BaseDialog
         v-model="deleteDialog"
-        :title="$t('settings.backup.delete-backup')"
+        :title="$tc('settings.backup.delete-backup')"
         color="error"
         :icon="$globals.icons.alertCircle"
         @confirm="deleteBackup()"
@@ -38,7 +38,7 @@
           </BaseButton>
         </v-card-actions>
         <p class="caption pb-0 mb-1 text-center">
-          {{ selected.name }}
+          {{ selected }}
         </p>
       </BaseDialog>
 
@@ -47,9 +47,12 @@
           <v-card-text class="py-0 px-1">
             Backups a total snapshots of the database and data directory of the site. This includes all data and cannot
             be set to exclude subsets of data. You can think off this as a snapshot of Mealie at a specific time.
-            Currently, this backup mechanism is not cross-version and therefore cannot be used to migrate data between
-            versions (data migrations are not done automatically). These serve as a database agnostic way to export and
-            import data or backup the site to an external location.
+            Currently,
+            <b>
+              this backup mechanism is not cross-version and therefore cannot be used to migrate data between versions
+            </b>
+            (data migrations are not done automatically). These serve as a database agnostic way to export and import
+            data or backup the site to an external location.
           </v-card-text>
         </BaseCardSectionTitle>
         <BaseButton @click="createBackup"> {{ $t("settings.backup.create-heading") }} </BaseButton>
@@ -78,7 +81,7 @@
             >
               <v-icon> {{ $globals.icons.delete }} </v-icon>
             </v-btn>
-            <BaseButton small download :download-url="backupsFileNameDownload(item.name)" @click.stop />
+            <BaseButton small download :download-url="backupsFileNameDownload(item.name)" @click.stop="() => {}" />
           </template>
         </v-data-table>
         <v-divider></v-divider>
@@ -137,11 +140,15 @@ export default defineComponent({
     }
 
     async function restoreBackup(fileName: string) {
-      const { data } = await adminApi.backups.restore(fileName);
+      const { error } = await adminApi.backups.restore(fileName);
 
-      if (!data?.error) {
-        $auth.logout();
+      if (error) {
+        console.log(error);
+        state.importDialog = false;
+        return;
       }
+
+      $auth.logout();
     }
 
     const deleteTarget = ref("");

mealie/routes/admin/admin_backups.py

@@ -9,8 +9,8 @@ from mealie.core.security import create_file_token
 from mealie.pkgs.stats.fs_stats import pretty_size
 from mealie.routes._base import BaseAdminController, controller
 from mealie.schema.admin.backup import AllBackups, BackupFile
-from mealie.schema.response.responses import FileTokenResponse, SuccessResponse
-from mealie.services.backups_v2.backup_v2 import BackupV2
+from mealie.schema.response.responses import ErrorResponse, FileTokenResponse, SuccessResponse
+from mealie.services.backups_v2.backup_v2 import BackupSchemaMismatch, BackupV2
 
 router = APIRouter(prefix="/backups")
 
@@ -100,6 +100,11 @@ class AdminBackupController(BaseAdminController):
 
         try:
             backup.restore(file)
+        except BackupSchemaMismatch as e:
+            raise HTTPException(
+                status.HTTP_400_BAD_REQUEST,
+                ErrorResponse.respond("database backup schema version does not match current database"),
+            ) from e
         except Exception as e:
             raise HTTPException(status.HTTP_500_INTERNAL_SERVER_ERROR) from e
 

mealie/services/backups_v2/backup_file.py

@@ -5,6 +5,8 @@ from pathlib import Path
 
 
 class BackupContents:
+    _tables: dict = None
+
     def __init__(self, file: Path) -> None:
         self.base = file
         self.data_directory = self.base / "data"
@@ -22,9 +24,22 @@ class BackupContents:
 
         return True
 
+    def schema_version(self) -> str:
+        tables = self.read_tables()
+
+        alembic_version = tables.get("alembic_version", [])
+
+        if not alembic_version:
+            return ""
+
+        return alembic_version[0].get("version_num", "")
+
     def read_tables(self) -> dict:
-        with open(self.tables) as f:
-            return json.loads(f.read())
+        if self._tables is None:
+            with open(self.tables, "r") as f:
+                self._tables = json.load(f)
+
+        return self._tables
 
 
 class BackupFile:

mealie/services/backups_v2/backup_v2.py

@@ -9,6 +9,10 @@ from mealie.services.backups_v2.alchemy_exporter import AlchemyExporter
 from mealie.services.backups_v2.backup_file import BackupFile
 
 
+class BackupSchemaMismatch(Exception):
+    ...
+
+
 class BackupV2(BaseService):
     def __init__(self, db_url: str = None) -> None:
         super().__init__()
@@ -73,18 +77,28 @@ class BackupV2(BaseService):
             self._postgres()
 
         with backup as contents:
+            # ================================
+            # Validation
             if not contents.validate():
                 self.logger.error(
                     "Invalid backup file. file does not contain required elements (data directory and database.json"
                 )
                 raise ValueError("Invalid backup file")
 
-            # Purge the Database
+            database_json = contents.read_tables()
+
+            if not AlchemyExporter.validate_schemas(database_json, self.db_exporter.dump()):
+                self.logger.error("Invalid backup file. Database schemas do not match")
+                raise BackupSchemaMismatch("Invalid backup file. Database schemas do not match")
+
+            # ================================
+            # Purge Database
 
             self.logger.info("dropping all database tables")
             self.db_exporter.drop_all()
 
-            database_json = contents.read_tables()
+            # ================================
+            # Restore Database
 
             self.logger.info("importing database tables")
             self.db_exporter.restore(database_json)