base64UrlEncoding in Worker without Wrangler

const crypto = require('crypto');
const base64url = require('base64url');
const date = Math.floor(Date.now()/1000);
let header = {
  "alg": "RS256",
  "typ": "JWT"
};

let payload = {
  "iss": "",
  "sub": "",
  "scope": "https://www.googleapis.com/auth/adwords",
  "aud": "https://oauth2.googleapis.com/token",
  "exp": date + 3600,
  "iat": date
};

let encodedHeader = base64url.encode(JSON.stringify(header));
let encodedPayload = base64url.encode(JSON.stringify(payload));

let signatureInput = `${encodedHeader}.${encodedPayload}`;
let privateKey = ‘’; 

let signer = crypto.createSign('RSA-SHA256');
signer.update(signatureInput);

let signature = base64url.fromBase64(signer.sign(privateKey, 'base64'));

let jwt = `${encodedHeader}.${encodedPayload}.${signature}`;

console.log(jwt);

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