401错误的OAuth 1.0授权无效签名？

Question

我正在尝试从woocommerce获取数据，它需要OAuth 1.0授权。

尽管尝试了多种方式，尽管邮递员给了我200，但我仍然收到401错误“无效签名”。我相信问题出在hash_function位，但我不知道如何诊断或解决问题。

这是我的代码：

componentDidMount() {
  const key = 'xxxxxxx';
  const timeStamp = Math.floor(new Date().getTime()/1000);
  const nonce = crypto.randomBytes(16).toString('base64');

  let base_string = 'GET&http%3A%2F%2Flocalhost%3A8888%2Fwp-json%2Fwc%2Fv2%2Fproducts%2F28%2Fvariations&oauth_consumer_key%3Dxxxxxx%26oauth_nonce%3DtnnUqiEHxgT4zSRaXnZRLA%26oauth_signature_method%3DHMAC-SHA1%26oauth_timestamp%3D1533375490'

const oauth = OAuth({
   consumer: {
      key: 'xxxxxx',
      secret: 'xxxxx',
      signature_method: 'HMAC-SHA1',
      hash_function(base_string, key) {
        return crypto.createHmac('sha1', key).update(base_string).digest('base64');
      }
   },
});

  const request_data = {
  url: 'http://localhost:8888/wp-json/wc/v2/products/28/variations',
  method: 'GET',
};

const token = {
  key: 'xxxxxx',
  secret: 'xxxxx',
};

  fetch(request_data.url, {
    method: request_data.method,
    headers: oauth.toHeader(oauth.authorize(request_data, token))
  })
    .then(response => response.json())
    .then(response => {
      this.setState({
         products: response
      })
    })
}