@pushforge/builder/dist/lib/utils.js

A robust, cross-platform Web Push notification library that handles VAPID authentication and payload encryption following the Web Push Protocol standard. Works in Node.js 16+, Browsers, Deno, Bun and Cloudflare Workers.

import { base64UrlDecodeString, base64UrlEncode } from './base64.js';
/**
 * Converts an ArrayBuffer or Uint8Array to a string.
 *
 * @param {ArrayBuffer | Uint8Array} s - The input array to convert.
 * @returns {string} The resulting string representation of the input.
 */
export const stringFromArrayBuffer = (s) => {
    let result = '';
    for (const code of new Uint8Array(s))
        result += String.fromCharCode(code);
    return result;
};
/**
 * Cross-platform function to decode a Base64 string into a binary string.
 * Works in both browser and Node.js environments.
 *
 * @param {string} base64String - The Base64 encoded string to decode.
 * @returns {string} The decoded binary string.
 */
export const base64Decode = (base64String) => {
    // Add padding if needed
    const paddedBase64 = base64String.padEnd(base64String.length + ((4 - (base64String.length % 4 || 4)) % 4), '=');
    // Node.js environment
    if (typeof Buffer !== 'undefined') {
        return Buffer.from(paddedBase64, 'base64').toString('binary');
    }
    // Browser environment
    if (typeof atob === 'function') {
        return atob(paddedBase64);
    }
    // Pure JavaScript implementation for environments without atob or Buffer
    const characters = 'ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/=';
    let result = '';
    let i = 0;
    while (i < paddedBase64.length) {
        const enc1 = characters.indexOf(paddedBase64.charAt(i++));
        const enc2 = characters.indexOf(paddedBase64.charAt(i++));
        const enc3 = characters.indexOf(paddedBase64.charAt(i++));
        const enc4 = characters.indexOf(paddedBase64.charAt(i++));
        const char1 = (enc1 << 2) | (enc2 >> 4);
        const char2 = ((enc2 & 15) << 4) | (enc3 >> 2);
        const char3 = ((enc3 & 3) << 6) | enc4;
        result += String.fromCharCode(char1);
        if (enc3 !== 64)
            result += String.fromCharCode(char2);
        if (enc4 !== 64)
            result += String.fromCharCode(char3);
    }
    return result;
};
/**
 * Extracts the public key from a JSON Web Key (JWK) and encodes it in base64 URL format.
 *
 * @param {JsonWebKey} jwk - The JSON Web Key from which to extract the public key.
 * @returns {string} The base64 URL encoded public key.
 */
export const getPublicKeyFromJwk = (jwk) => base64UrlEncode(`\x04${base64Decode(base64UrlDecodeString(jwk.x))}${base64Decode(base64UrlDecodeString(jwk.y))}`);
/**
 * Concatenates multiple Uint8Array instances into a single Uint8Array.
 *
 * @param {Uint8Array[]} arrays - An array of Uint8Array instances to concatenate.
 * @returns {Uint8Array} A new Uint8Array containing all the concatenated data.
 */
export const concatTypedArrays = (arrays) => {
    const length = arrays.reduce((accumulator, current) => accumulator + current.byteLength, 0);
    let index = 0;
    const targetArray = new Uint8Array(length);
    for (const array of arrays) {
        targetArray.set(array, index);
        index += array.byteLength;
    }
    return targetArray;
};