Tiny & Simply 'Map'/'Array'-based storage with .save() method

Features

• VERY easy to use
• "One File - One Storage Exemplar" mechanism (bugs & multi-load protection)
• Safe asynchronous save() (protection from multi-saving)
• "Exact key types": you can only use the specified keys, e.g. day ${number} (day 6, day 293, day 32, etc., but not hour 7)
• Additional Map methods: hasValue(), getKey(), filter() & easy JSON convertion
• Pretty JSON format (depth=1)

API

• class Storage <V? extends JSONSupported, K? extends string> default export

• extends Map<K, V>
• constructor (path: string, autosave?: boolean | number)
• field path: string
• hasValue (value: V): boolean
• getKey (value: V, single?: boolean): K[]
• filter (callbackfn: (value: V, key: K, map: Map<K, V>) => boolean): Map<K, V>
• async save (): Promise<void>
• getter asJSON: string
• [Symbol.toStringTag]: string
• static create <V? extends JSONSupported, K? extends string> (...params: ConstructorParameters<typeof Storage>): Storage<V, K>
• static asJSON (map: Map<string, JSONSupported>): string
• static field oneFile_oneStorage: boolean

• class ArrayStorage <V? extends JSONSupported>

• extends Array<V>
• private constructor ()
• field path: string
• async save (): Promise<void>
• getter asJSON: string
• [Symbol.toStringTag]: string
• static create <V? extends JSONSupported> (path: string, autosave?: boolean | number): ArrayStorage<V>
• static asJSON (arr: JSONSupported[]): string
• static field oneFile_oneStorage: boolean

Requirements

• NodeJS, recommended v18 or newer

Setup

1. Install storage via npm:

npm i @eds-fw/storage

2. Use storage:

//file.js, type: CJS
const { Storage } = require("@eds-fw/storage");
const scores = new Storage(
    "./scores_data.json", //Warning! Path is calculated from CWD
    60_000 //Autosave timeout. Will be saved automatically every minute
);
scores.set("me", 186);
scores.save();
scores.set("john", 231);
if (storage.has("peter"))
    storage.delete("peter");
console.log(storage.asJSON());
/* Output (pretty):
{
    "me": 186,
    "john": 231
}
*/

Or, using TypeScript and "exact key types":

//file.ts
import { Storage } from "@eds-fw/storage";
type Keys_t = `score_${string}` | `bestScore_${string}`;
const scores = new Storage<number, Keys_t>(
    "./scores.json",
    60_000
);
scores.set("score_me", 132); //OK
scores.set("score_john", 452); //OK
scores.set("bestScore_me", 972); //OK
scores.set("previousScore_me", 274); //TypeScript Error

Source (git)

Issues (git)