@indb/database v0.3.5

@indb/database

The database package exposes a type-safe, promise-based wrapper around the IndexedDB API.

API Docs

Example

An example database looks something like this:

import { Database, type SchemaDefinition } from '@indb/database';

type Todo = {
  id: string;
  listId: string;
  title: string;
  createdAt: number;
};

type List = {
  id: string;
  title: string;
};

type Tables = {
  todos: Todo;
  lists: List;
};

const DATABASE_NAME = 'todos';
const SCHEMA: SchemaDefinition<Tables> = {
  version: 1,
  stores: {
    lists: {
      keyPath: 'id',
    },
    todos: {
      keyPath: 'id',
      indices: {
        listId: {},
      },
    },
  },
};

const database = new Database<Tables>(DATABASE_NAME, SCHEMA);

This creates a new database, and will create the lists and todos stores, as well as a listId index on the todos store, so you can easily pull all the todos that are related to a specific list.

Features

Automatic Schema Migrations

Schemas are defined giving names of stores, key paths, and indices, and whenever the version of the schema is changed @indb/database will diff the current state of the schema and the requested schema and make the desired changes.

Schemas are type-safe, in that they must define table definitions for all of the types registered with the database.

Type-safe

The Tables type passed to the database will make sure you only interact with tables named in the type, and will cast all data from the associated tables with that type.

Additionally, schema definitions requre that each table have a definition, and that the key and index paths are valid paths (even deep paths are checked).

Promise-based

All of the actions you can take on the database return Promises, so you don't have to work with the lower-level onerror and oncomplete etc. handlers of the various objects produced by calls to the IndexedDB API.

Event Dispatching

Every mutation to the database dispatches an action that can be listened for via a handler on database.addEventListener('changed', handler). Additionally, every change to the database will also dispatch an event on a BroadcastChannel that other instances of Database in other tabs and windows will listen to.

So, Database instances act as event aggregators for all other Database instances, meaning that changes in other tabs or windows will dispatch events in others, allowing data to keep up to date no matter where the actions occur.

The stores package provides some classes that are designed to efficiently keep in-memory representations of parts of the database by using this event dispatching functionality.