Property 'nonce_supported' does not exist on type 'string | JwtPayload'

从复现中的 jwt.decode 调用开始，检查 @types/jsonwebtoken 8.5.8 如何为其 payload 定义类型；将其与库在 8.5.1 中的用法进行比较。当示例对 nonce_supported、iss、aud 和 exp 的访问能够无错误地通过类型检查时，即表示完成。

Description

@types/jsonwebtoken 8.5.8 break the nestjs application,

sample code

import * as jwt from 'jsonwebtoken';

//  identityToken, nonce are props from apple signin

const decoded = jwt.decode(identityToken, { complete: true });

// ...

if (decoded.payload.nonce_supported && nonce !== NONCE) {
  // ...
}

if (!decoded.payload.iss || decoded.payload.iss !== APPLE_BASE_URL) {
  // ...
}

if (decoded.payload.aud !== 'my.aud.string') {
  // ...
}

if (Number(decoded.payload.exp) * 1000 < my_expr_limit) {
  // ...
}

error message:

Property 'nonce_supported' does not exist on type 'string | JwtPayload'.
  Property 'nonce_supported' does not exist on type 'string'.

Property 'iss' does not exist on type 'string | JwtPayload'.
  Property 'iss' does not exist on type 'string'.

Property 'aud' does not exist on type 'string | JwtPayload'.
  Property 'aud' does not exist on type 'string'.

Property 'exp' does not exist on type 'string | JwtPayload'.
  Property 'exp' does not exist on type 'string'.

Reproduction

1. create a nestjs app
2. add "jsonwebtoken": "^8.5.1", to your package.json
3. implement apple sign in as the sample above
4. npm install
5. npm run start then you can see the errors

Environment

Please provide the following:

• Version of this library used: 8.5.1
• Version of the platform or framework used, if applicable: node 16.13.1, npm 8.1.2
• Other relevant versions (language, server software, OS, browser): OS Mac M1
• Other modules/plugins/libraries that might be involved: "@types/jsonwebtoken": "8.5.8",