How to integrate google APIs to your application

API is a way to use features of other applications in our application. Google has several APIs that could be used in our applications.

In this article, we will see how to integrate Google API with our application.

Prerequisites

Account in Google Cloud Platform

Steps

1. Create Google Cloud Project

Create Project

From the sidebar, go to APIs & Services > Library.
Search for the API to enable, here we are enabling google sheets API.
Click on Enable.

2. Create Credentials

Create Credentials

Now create credentials for the API. For this, there are 3 ways
- OAuth 2.0: to access user data on their behalf.
- API Key: to access public data.
- Service Account: to access our data on behalf of our application.
here we are using a service account.
Add a service account name and click on create.
Fill the required details
Click on Done and download the JSON file which contains the credentials.

3. Integrate API using the credentials

Create an .env file and add GOOGLE_SHEET_CLIENT_EMAIL, GOOGLE_SHEET_PRIVATE_KEY and GOOGLE_SHEET_ID from the downloaded JSON file.
For the private key, include everything from “-----BEGIN PRIVATE KEY-----” to “-----END PRIVATE KEY-----”
Install googleapis package using your package manager.

import { google } from 'googleapis';

export default async function getSheetData() {
    // create auth client
    const auth = new google.auth.GoogleAuth({
        credentials: {
            client_email: process.env.GOOGLE_SHEET_CLIENT_EMAIL,
            private_key: process.env.GOOGLE_SHEET_PRIVATE_KEY,
        },
        scopes: [
            'https://www.googleapis.com/auth/spreadsheets', // to read and write spreadsheets
            'https://www.googleapis.com/auth/drive', // to create a new spreadsheet
        ],
    });

    // create client instance
    const client = await auth.getClient();

    // create google sheet instance
    const sheetInstance = google.sheets({ version: 'v4', auth: client });

    // get all data in range
    const { data } = await sheetInstance.spreadsheets.values.get({
        spreadsheetId: process.env.GOOGLE_SHEET_ID,
        range: 'sheet1', // this is sheet name
    });

    return data.values;
}