Add migration 2: remove old data.

src/config.rs

@@ -6,7 +6,7 @@ use thiserror::Error;
 
 /// Shortcut to defining db migration versions. Will probably
 /// eventually be moved to a config file.
-const MIGRATION_VERSION: u32 = 1;
+const MIGRATION_VERSION: u32 = 2;
 
 #[derive(Error, Debug)]
 pub enum ConfigError {

src/db/data_migrations.rs

@@ -7,6 +7,7 @@ pub(super) type DataMigration = (fn(&Database) -> Result<(), DataError>, &'stati
 
 static MIGRATIONS: phf::Map<u32, DataMigration> = phf_map! {
     1u32 => (add_room_user_variable_count, "add_room_user_variable_count"),
+    2u32 => (delete_v0_schema, "delete_v0_schema"),
 };
 
 pub fn get_migrations(versions: &[u32]) -> Result<Vec<DataMigration>, MigrationError> {

src/db/variables/migrations.rs

@@ -92,3 +92,19 @@ pub(in crate::db) fn add_room_user_variable_count(db: &Database) -> Result<(), D
     tx_result?; //For some reason, it cannot infer the type
     Ok(())
 }
+
+pub(in crate::db) fn delete_v0_schema(db: &Database) -> Result<(), DataError> {
+    let mut vars = db.variables.0.scan_prefix("");
+    let mut batch = Batch::default();
+
+    while let Some(Ok((key, _))) = vars.next() {
+        let key = key.to_vec();
+
+        if !key.contains(&0xff) {
+            batch.remove(key);
+        }
+    }
+
+    db.variables.0.apply_batch(batch)?;
+    Ok(())
+}