＆＃34;无效的JWT签名。＆＃34;与meteor-google-oauth-jwt

Question

我尝试按照以下说明以编程方式提交sitemap.xml： https://developers.google.com/webmaster-tools/search-console-api-original/v3/sitemaps/submit#auth

我做：

// Just call this once to set JWT
HTTPJWT.setJWTOptions({
    email : "[ client ID up to the first dot ]@developer.gserviceaccount.com",
    key : Assets.getText("key.pem"), // Get key file from assets
    scopes : [
        "https://www.googleapis.com/auth/webmasters"
    ],
});

var submitUrl = "https://www.googleapis.com/webmasters/v3/sites/https%3A%2F%2Fwww.spoticle.com/sitemaps/https%3A%2F%2Fwww.spoticle.com%2Fsitemap.xml";
var result = HTTPJWT.get(submitUrl);

......结果如下：

错误：失败[400] {＆＃34;错误＆＃34; ：＆＃34; invalid_grant＆＃34;，＆＃34; error_description＆＃34; ：＆＃34;无效的JWT签名。＆＃34; }

然而，我可以通过以下方式生成JWT：

var jwt = GoogleOAuthJWT.encodeJWT({
    email : "[ client ID up to the first dot ]@developer.gserviceaccount.com",
    key : Assets.getText("key.pem"), // Get key file from assets
    scopes : [
        "https://www.googleapis.com/auth/webmasters"
    ]
});

...但我不知道如何验证此令牌是否有效。

任何帮助表示赞赏。感谢。