I think there's something wrong with your oauth2Client your not requesting authorization of the user.
Try my sample here it should work out of the box.
const fs = require('fs').promises;
const path = require('path');
const process = require('process');
const {authenticate} = require('@google-cloud/local-auth');
const {google} = require('googleapis');
// If modifying these scopes, delete token.json.
const SCOPES = ['https://www.googleapis.com/auth/calendar.readonly'];
// The file token.json stores the user's access and refresh tokens, and is
// created automatically when the authorization flow completes for the first
// time.
const TOKEN_PATH = path.join(process.cwd(), 'token.json');
const CREDENTIALS_PATH = 'C:\\Development\\FreeLance\\GoogleSamples\\Credentials\\CredWebEverything.json';
/**
* Reads previously authorized credentials from the save file.
*
* @return {Promise<OAuth2Client|null>}
*/
async function loadSavedCredentialsIfExist() {
try {
const content = await fs.readFile(TOKEN_PATH);
const credentials = JSON.parse(content);
return google.auth.fromJSON(credentials);
} catch (err) {
return null;
}
}
/**
* Serializes credentials to a file compatible with GoogleAUth.fromJSON.
*
* @param {OAuth2Client} client
* @return {Promise<void>}
*/
async function saveCredentials(client) {
const content = await fs.readFile(CREDENTIALS_PATH);
const keys = JSON.parse(content);
const key = keys.installed || keys.web;
const payload = JSON.stringify({
type: 'authorized_user',
client_id: key.client_id,
client_secret: key.client_secret,
refresh_token: client.credentials.refresh_token,
});
await fs.writeFile(TOKEN_PATH, payload);
}
/**
* Load or request or authorization to call APIs.
*
*/
async function authorize() {
let client = await loadSavedCredentialsIfExist();
if (client) {
return client;
}
client = await authenticate({
scopes: SCOPES,
keyfilePath: CREDENTIALS_PATH,
});
if (client.credentials) {
await saveCredentials(client);
}
return client;
}
/**
* Lists the next 10 events on the user's primary calendar.
* @param {google.auth.OAuth2} auth An authorized OAuth2 client.
*/
async function listEvents(auth) {
const calendar = google.calendar({version: 'v3', auth});
const res = await calendar.events.list({
calendarId: 'primary',
timeMin: new Date().toISOString(),
maxResults: 10,
singleEvents: true,
orderBy: 'startTime',
});
const events = res.data.items;
if (!events || events.length === 0) {
console.log('No upcoming events found.');
return;
}
console.log('Upcoming 10 events:');
events.map((event, i) => {
const start = event.start.dateTime || event.start.date;
console.log(`${start} - ${event.summary}`);
});
}
authorize().then(listEvents).catch(console.error);