@jkcfg/kubernetes/base64.js

jk Kubernetes library

const alphabet = 'ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/';
const chars = alphabet.split('');
function encode(bytes) {
    const triples = Math.floor(bytes.length / 3);
    const tripleLen = triples * 3;
    let encoded = '';
    for (let i = 0; i < tripleLen; i += 3) {
        const bits = (bytes[i] << 16) | (bytes[i + 1] << 8) | bytes[i + 2];
        const c1 = chars[bits >> 18];
        const c2 = chars[(bits >> 12) & 0x3f];
        const c3 = chars[(bits >> 6) & 0x3f];
        const c4 = chars[bits & 0x3f];
        encoded = `${encoded}${c1}${c2}${c3}${c4}`;
    }
    switch (bytes.length - tripleLen) {
        case 1: {
            // left with 8 bits; pad to 12 bits to get two six-bit characters
            const last = bytes[bytes.length - 1];
            const c1 = chars[last >> 2];
            const c2 = chars[(last & 0x03) << 4];
            encoded = `${encoded}${c1}${c2}==`;
            break;
        }
        case 2: {
            // left with 16 bits; pad to 18 bits to get three six-bit characters
            const last2 = (bytes[bytes.length - 2] << 10) | (bytes[bytes.length - 1] << 2);
            const c1 = chars[last2 >> 12];
            const c2 = chars[(last2 >> 6) & 0x3f];
            const c3 = chars[last2 & 0x3f];
            encoded = `${encoded}${c1}${c2}${c3}=`;
            break;
        }
        default:
            break;
    }
    return encoded;
}
// Encode a native string (UTF16) of ASCII characters as an array of UTF8 bytes.
function ascii2bytes(str) {
    const result = new Array(str.length);
    for (let i = 0; i < str.length; i += 1) {
        result[i] = str.charCodeAt(i);
    }
    return result;
}
export { encode, ascii2bytes };