@cosmos-kit/keplr-extension/esm/extension/session.js

cosmos-kit wallet connector

export class ExpiringLocalStorage {
    /**
     * Add an item to an array in local storage with an expiration time.
     * @param {string} key - The key under which the array is stored.
     * @param {*} value - The value to be added.
     * @param {number} ttl - Time to live in milliseconds.
     */
    static addItem(key, value, ttl) {
        const now = new Date();
        // Create a new item with value and expiry
        const newItem = {
            value: value,
            expiry: now.getTime() + ttl,
        };
        // Get existing items from local storage
        const itemStr = localStorage.getItem(key);
        const items = itemStr ? JSON.parse(itemStr) : [];
        // Add the new item to the array
        items.push(newItem);
        // Store the updated array in local storage
        localStorage.setItem(key, JSON.stringify(items));
    }
    /**
     * Get all valid (non-expired) items from an array in local storage.
     * @param {string} key - The key of the array to retrieve.
     * @returns {Array} An array of valid items.
     */
    static getItems(key) {
        const itemStr = localStorage.getItem(key);
        // If the item doesn't exist, return an empty array
        if (!itemStr) {
            return [];
        }
        const items = JSON.parse(itemStr);
        const now = new Date();
        const validItems = [];
        // Filter out expired items
        for (const item of items) {
            if (now.getTime() <= item.expiry) {
                validItems.push(item.value);
            }
        }
        // Update local storage with only valid items
        localStorage.setItem(key, JSON.stringify(validItems.map((value) => ({
            value,
            expiry: items.find((item) => item.value === value).expiry,
        }))));
        return validItems;
    }
    /**
     * Remove a specific item from the array in local storage.
     * @param {string} key - The key of the array.
     * @param {*} value - The value to be removed.
     */
    static removeItem(key, value) {
        const itemStr = localStorage.getItem(key);
        // If the item doesn't exist, return
        if (!itemStr) {
            return;
        }
        let items = JSON.parse(itemStr);
        // Filter out the item to be removed
        items = items.filter((item) => item.value !== value);
        // Update local storage with the remaining items
        localStorage.setItem(key, JSON.stringify(items));
    }
}
// Usage example:
// Add items with different TTLs
// ExpiringLocalStorage.addItem('myArray', 'item1', 10000); // Expires in 10 seconds
// ExpiringLocalStorage.addItem('myArray', 'item2', 20000); // Expires in 20 seconds
// Get all valid items (non-expired)
// console.log(ExpiringLocalStorage.getItems('myArray'));
// Remove a specific item
// ExpiringLocalStorage.removeItem('myArray', 'item1');