@faizaanceg/pandora/dist/kv.mjs

A tiny wrapper over LocalStorage to improve DX

export class KeyValueStore {
    static DEFAULTS = {
        shouldPersist: false,
        ttl: Number.MAX_SAFE_INTEGER,
    };
    adapter;
    subscriptions = new Map();
    constructor(adapter) {
        this.adapter = adapter;
    }
    getInternal(key) {
        try {
            const internalItem = this.adapter.getItem(key);
            if (internalItem === null) {
                return;
            }
            const item = JSON.parse(internalItem);
            const isExpired = Date.now() >= item.createdOn + item.ttl;
            return isExpired ? this.remove(key) : item;
        }
        catch {
            return;
        }
    }
    signal(key) {
        if (this.subscriptions.has(key)) {
            this.subscriptions.get(key)?.forEach((signal) => signal?.());
        }
    }
    get(key, defaultValue) {
        const item = this.getInternal(key);
        return item ? item.value : defaultValue ?? null;
    }
    set(key, value, opts = {}) {
        this.adapter.setItem(key, JSON.stringify({
            createdOn: Date.now(),
            value,
            ...KeyValueStore.DEFAULTS,
            ...opts,
        }));
        this.signal(key);
    }
    subscribe(key, signal) {
        let count = 0;
        let signals = [signal];
        if (this.subscriptions.has(key)) {
            signals = this.subscriptions.get(key);
            count = signals.push(signal);
        }
        this.subscriptions.set(key, signals);
        return () => this.removeSubscription(key, count);
    }
    removeSubscription(key, count) {
        if (this.subscriptions.has(key)) {
            if (count === -1) {
                this.subscriptions.delete(key);
            }
            else {
                const signals = this.subscriptions.get(key);
                delete signals[count];
            }
        }
    }
    forEach(cb) {
        const size = this.adapter.length;
        for (let i = 0; i < size; i++) {
            const key = this.adapter.key(i);
            if (key === null) {
                continue;
            }
            const item = this.getInternal(key);
            if (item) {
                cb(key, item);
            }
        }
    }
    remove(key) {
        this.adapter.removeItem(key);
        this.signal(key);
        this.removeSubscription(key, -1);
    }
    clear(removeAll = false) {
        const perishedItems = [];
        this.forEach((key, item) => {
            if (!item.shouldPersist || removeAll) {
                perishedItems.push([key, item.value]);
            }
        });
        perishedItems.forEach(([key]) => this.remove(key));
        return Object.fromEntries(perishedItems);
    }
    getSnapshot() {
        const items = [];
        this.forEach((key, item) => {
            items.push([key, item.value]);
        });
        return Object.fromEntries(items);
    }
}