I am not able to figure out a proper flow in accessing google calendar rest API’s without using inbuilt methods of googleapis liberary to modify the event/access them. All the solutions found to acccess google calendar uses in-built methods of googleapis and also https://developers.google.com/calendar/caldav/v2/guide#connecting_to_googles_caldav_server says we need to perform oauth and then connect.

Note: can use module for oAuth and not for modifying/accessing calendar

something like below

const express = require("express");
const { google } = require("googleapis");
const dotenv = require("dotenv");
const axios = require("axios");
app.get("/request", async (req, res) => {
  const oauth2Client = new google.auth.OAuth2(
    process.env.CLIENT_ID,
    process.env.SECRET_ID,
    process.env.REDIRECT_URL
  );
  const token = oauth2Client.credentials.access_token;

  try {
    const response = await axios({
      method: "PROPFIND", // Use PROPFIND to fetch calendar data from CalDAV
      url: `https://apidata.googleusercontent.com/caldav/v2/${calid}/events/`, // Google CalDAV endpoint
      headers: {
        Authorization: `Bearer ${token}`,
        Depth: "1",
        "Content-Type": "application/xml"
      },
      data: `
        <C:calendar-query xmlns:D="DAV:" xmlns:C="urn:ietf:params:xml:ns:caldav">
          <D:prop>
            <D:getetag />
            <C:calendar-data />
          </D:prop>
          <C:filter>
            <C:comp-filter name="VCALENDAR">
              <C:comp-filter name="VEVENT" />
            </C:comp-filter>
          </C:filter>
        </C:calendar-query>
      `
    });

    console.log("CalDAV Response:", response.data);
  } catch (error) {
    console.error("Error fetching calendar data:", error);
  }
});