feat: implement database backup

packages/core/database/backup.js

@@ -0,0 +1,34 @@
+export default class Backup {
+  /**
+   *
+   * @param {import("../api/index.js").default} db
+   */
+  constructor(db) {
+    this._db = db;
+  }
+
+  async export(encrypt = false) {
+    const keys = await this._db.context.getAllKeys();
+    const db = Object.fromEntries(await this._db.context.readMulti(keys));
+    if (encrypt) {
+      const key = await this._db.user.key();
+      return JSON.stringify(
+        await this._db.context.encrypt(key, JSON.stringify(db))
+      );
+    }
+    return JSON.stringify(db);
+  }
+
+  async import(data) {
+    let backup = JSON.parse(data);
+    //check if we have encrypted data
+    if (backup.salt && backup.iv) {
+      const key = await this._db.user.key();
+      backup = JSON.parse(await this._db.context.decrypt(key, backup));
+    }
+    for (let key in backup) {
+      let value = backup[key];
+      await this._db.context.write(key, value);
+    }
+  }
+}