URL-safe encoding/decoding of JSON data like Pendo does it

index.js

// Given large data payload with UTF-6 encoding, emojis etc.
const data = [{...}]

const string = JSON.stringify(data); // JSON to string
const byteArray = new TextEncoder().encode(string) // Convert to bytes
const deflatedByteArrayBuffer = zlib.deflateSync(byteArray); // Compress
const encoded = deflatedByteArrayBuffer.toString("base64url"); // Encode for safe transfer e.g. via URL

// URL-safe output
console.log(encoded)

// -----

const decoded = Buffer.from(encoded, "base64url")
const inflatedBuffer = zlib.inflateSync(decoded); // Decompress
const dataString = new TextDecoder().decode(inflatedBuffer) // Bytes to string
const originalData = JSON.parse(dataString); // string to JSON

// Original data
console.log(originalData)