how to get client secret for a service account for google api - google-api-nodejs-client

Question

This page:
https://console.cloud.google.com/iam-admin/serviceaccounts
if you go into an individual project that has a service account, and use the three dots on that row to execute the action "Get Key", it will generate a json that looks like:
{
"type": "service_account",
"project_id": "project name",
"private_key_id": "sdfljsdlfsdljkf",
"private_key": "-----BEGIN PRIVATE KEY-----\nsldjflsdjfkljsdf\n-----END PRIVATE KEY-----\n",
"client_email": "user#projectname.iam.gserviceaccount.com",
"client_id": "9797979797998",
"auth_uri": "https://accounts.google.com/o/oauth2/auth",
"token_uri": "https://oauth2.googleapis.com/token",
"auth_provider_x509_cert_url": "https://www.googleapis.com/oauth2/v1/certs",
"client_x509_cert_url": "https://www.googleapis.com/robot/v1/metadata/x509/projectname.iam.gserviceaccount.com"
}
This doesn't match with what is needed for google.auth.OAuth2(client_id, client_secret, redirect_uris[])
What do I do to create a token to use with google spreadsheets api that uses this key information. It seems that the redirect_uris and the client secret are missing.
Update: the goal of this is to send google calendar events as other users under our domain.

Answer 1

I believe your goal and situation as follows.
You want to use Sheets API using the service account.
You want to achieve this using googleapis for Node.js.
You have already enabled Sheets API at API console.
In this case, google.auth.JWT is used instead of google.auth.OAuth2(). A simple sample script for this is as follows.
Sample script:
Before you use this script, please set the variable for google.auth.JWT(). In this case, as a samplet, client_email and private_key are set. And please set Spreadsheet ID. And, in this case, please share your sample Google Spreadsheet in your Google Drive with the email of the service account. By this, the service account can read the Spreadsheet.
const { google } = require("googleapis");
const spreadsheetId = "###"; // Please set Spreadsheet ID.
const auth = new google.auth.JWT(
"###", // Please set client_email here.
null,
"-----BEGIN PRIVATE KEY-----\n###\n-----END PRIVATE KEY-----\n", // Please set private_key here,
["https://www.googleapis.com/auth/spreadsheets.readonly"],
null
);
const sheets = google.sheets({ version: "v4", auth: auth });
sheets.spreadsheets
.get({ spreadsheetId: spreadsheetId })
.then(({ data }) => console.log(data))
.catch((err) => console.log(err));
Note:
When you run above script and an error like The caller does not have permission occurs, please confirm that whether the Spreadsheet of spreadsheetId is shared with the email of the service account again. If it is not, please share it with the email of the service account.
Please confirm whether the version of googleapis is the latest one.
References:
googleapis for Node.js
Method: spreadsheets.get