在emailTransporter.js我的代码如下。

const nodemailer = require('nodemailer');
const { google } = require("googleapis");
const path = require('path');
const OAuth2 = google.auth.OAuth2;

require('dotenv').config({path: path.join(__dirname, '.env')});

const oauth2Client = new OAuth2(
    process.env.CLIENT_ID, // ClientID
    process.env.CLIENT_SECRET, // Client Secret
    "https://developers.google.com/oauthplayground" // Redirect URL
);

oauth2Client.setCredentials({
    refresh_token: process.env.REFRESH_TOKEN
});
const accessToken = oauth2Client.getAccessToken();

let transporter = nodemailer.createTransport({
    host: 'smtp.gmail.com',
    port: 465,
    secure: true,
    auth: {
        type: "OAuth2",
        user: process.env.USER_EMAIL, 
        clientId: process.env.CLIENT_ID,
        clientSecret: process.env.CLIENT_SECRET,
        refreshToken: process.env.REFRESH_TOKEN,
        accessToken: accessToken
    },
    tls: {
        rejectUnauthorized: false
    }
});

module.exports = transporter;

在auth.js中，我使用emailTransporter.js中的emailTransporter导出来发送一些电子邮件选项。但是node给我的错误是这样的：
D：\nodejs\node_modules\gaxios\build\src\gaxios. js：129 throw new common_1.GaxiosError（Request failed with status code ${translatedResponse.status}，opts，translatedResponse）;^
GaxiosError：unauthorized_client在Gaxios。_request（D：\nodejs\node_modules\gaxios\build\src\gaxios。js：一百二十九：23）在processTicksAndRejections（节点：internal/process/task_queues：九十六：5）at async OAuth2Client.refreshTokenNoCache（D：\nodejs\node_modules\google-auth-library\build\src\auth\oauth2client.js：一百七十四：21）at async OAuth2Client.refreshAccessTokenAsync（D：\nodejs\node_modules\google-auth-library\build\src\auth\oauth2client.js：一百九十八：19）at async OAuth2Client.getAccessTokenAsync（D：\nodejs\node_modules\google-auth-library\build\src\auth\oauth2client.js：二百二十七：23）{响应：{配置：{方法：'POST'，url：'https：//oauth2.googleapis.com/token'，data：'refresh_token = 1%2F%2F04PvTQnD4_www.example.com & client_secret = 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 & grant_type = refresh_token'，header：86nCgYIARAAGAQSNwF-L9IrTdRMaV9mdIMhyEhFeJeKGSvqYnbgkCw-18aF7ZFmRgpWoWiQM3EXozwMiXzvfYwmAwc&client_id=543495663437-d59lg6u1a77o9a2uinf83idb0md991l9.apps.googleusercontent.com'application/x-www-form-urlencoded'，' User-Agent'：'google-api-nodejs-client/7.11.0'，' x-goog-api-client'：'gl-node/16.13.2 auth/7.11.0'，接受：'application/json '}，paramsSerializer：[函数：paramsSerializer]，函数体：2019 - 01 - 22 00：00：00：00 Copyright © 2018 - 2019 www.d59lg6u1a.com版权所有77o9a2uinf83idb0md991l9.apps.googleusercontent.com&client_secret = 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 & grant_type = refresh_token'，validateStatus：[Function：validateStatus]，responseType：'json '}，数据：{error：'unauthorized_client'，error_description：'Unauthorized '}，标头：{'alt-svc'：'h3 ="：443"; ma = 2592000，h3 - 29 ="：443"; ma = 2592000，h3-Q050 ="：443"; ma = 2592000，h3-Q046 ="：443"; ma = 2592000，h3-Q043 ="：443"; ma = 2592000，quic ="：443"; ma = 2592000 v ="46，43"'，' cache-control'：'no-cache，no-store，max-age = 0，must-revalidate'，连接：'close'，'content-encoding'：'gzip'，'content-type'：'application/json; charset = utf-8'，日期：'Wed，19 Jan 2022 03：47：31 GMT'，过期时间：'Mon，01 Jan 1990 00：00：00 GMT'，pragma：'no-cache'，服务器：'HTTPServer2上的脚手架'，'transfer-encoding'：'chunked'，vary：'Origin，X-Origin，Refererer'，' x-content-type-options'：'nosniff'，' x-frame-options'：'SAMEORIGIN'，' x-xss-protection'：“0”}，状态：401，状态文本：“未经授权”，请求：{responseURL：'https：//oauth2.googleapis.com/token '}}，配置：{method：'POST'，url：'https：//oauth2.googleapis.com/token'，data：'refresh_token = 1%2F%2F04PvTQnD4_www.example.com & client_secret = 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 & grant_type = refresh_token'，header：{'Content-Type '：'application/x-www-form-urlencoded'，' User-Agent'：86nCgYIARAAGAQSNwF-L9IrTdRMaV9mdIMhyEhFeJeKGSvqYnbgkCw-18aF7ZFmRgpWoWiQM3EXozwMiXzvfYwmAwc&client_id=543495663437-d59lg6u1a77o9a2uinf83idb0md991l9.apps.googleusercontent.com'gl-node/16.13.2 auth/7.11.0'，接受：'application/json '}，paramsSerializer：[函数：paramsSerializer]，函数体：2019 - 01 - 22 00：00：00：00 Copyright © 2018 - 2019 www.d59lg6u1a.com版权所有77o9a2uinf83idb0md991l9.apps.googleusercontent.com&client_secret = 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 & grant_type = refresh_token'，validateStatus：[Function：validateStatus]，responseType：'json '}，代码：'401 '} 'refresh_token=1%2F%2F04PvTQnD4_86nCgYIARAAGAQSNwF-L9IrTdRMaV9mdIMhyEhFeJeKGSvqYnbgkCw-18aF7ZFmRgpWoWiQM3EXozwMiXzvfYwmAwc&client_id=543495663437-d59lg6u1a77o9a2uinf83idb0md991l9.apps.googleusercontent.com&client_secret=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&grant_type=refresh_token', validateStatus: [Function: validateStatus], responseType: 'json' }, code: '401' }