@yagisumi/sqlite3-storage

A simple key-value store like localStorage using better-sqlite3.

Installation

$ npm i @yagisumi/sqlite3-storage

Usage

• javascript

const Database = require('@yagisumi/sqlite3-storage').Database;

const db = new Database(':memory:');
const storage = db.getStorage('foo');
storage.setItem('key1', 'value1');
let v = storage.getItem('key1');

for (let kv of storage) {
  console.log(kv.key, kv.value);
}

storage.clear();

• typescript

import { Database } from '@yagisumi/sqlite3-storage';

// ...

Remarks

• Note that SQLite3 exceptions can be thrown from anywhere.

• When setting many items, you should do in a transaction. Otherwise it takes a lot of time.

db.transaction({ rollback: false }, () => {
  for (let i = 0; i < 100; i++) {
    storage.setItem(`key${i}`, `value${i}`)
  }
})

Example

example with typescript

import { Database, Sqlite3Storage } from "@yagisumi/sqlite3-storage"
import serialijse from "serialijse"

class Store<T> {
  constructor(private storage: Sqlite3Storage.Storage) {}
  set(key: string, obj: T) {
    this.storage.setItem(key, serialijse.serialize(obj))
  }
  get(key: string) {
    const v = this.storage.getItem(key)
    if (v) {
      return serialijse.deserialize<T>(v)
    } else {
      return null
    }
  }
}

class Person {
  constructor(readonly name: string, readonly age: number) {}
}
serialijse.declarePersistable(Person)

const db = new Database("temp.db")
const storage = db.getStorage("people")
const store = new Store<Person>(storage)

const people = [new Person("Mike", 39), new Person("Bob", 44)]

db.transaction(null, () => {
  for (let p of people) {
    store.set(p.name, p)
  }
})

for (let p of people) {
  console.log(store.get(p.name))
}

API Reference

class Database {
  constructor(path_or_sqlite3: string | BetterSqlite3.Database, options?: Sqlite3Storage.DatabaseOptions);
  readonly inTransaction: boolean;
  close(): void;
  getStorage(name: string): Sqlite3Storage.Storage;
  transaction(options: Sqlite3Storage.TransactionOptions | null | undefined, func: () => void): void;
}

namespace Sqlite3Storage {
  interface Storage {
    readonly db: Database;
    readonly storageName: string;
    readonly length: number;
    clear(): void;
    getItem(key: string): string | null;
    key(index: number): string | null;
    at(index: number): KeyValue | null;
    removeItem(key: string): void;
    setItem(key: string, value: string): void;
  }
  interface KeyValue {
    key: string;
    value: string;
  }
  interface DatabaseOptions {
    // better-sqlite3 options
    memory?: boolean;
    readonly?: boolean;
    fileMustExist?: boolean;
    timeout?: number;
    verbose?: (message?: any, ...additionalArgs: any[]) => void;
  }
  interface TransactionOptions {
    rollback?: boolean; // default: true
    type?: TransactionType; // "DEFERRED" | "IMMEDIATE" | "EXCLUSIVE"
  }
}

Documentation

https://yagisumi.github.io/node-sqlite3-storage/

License

MIT License