How to Use Google OAuth 2.0 to Access Google APIs with Refresh Token?

The Google OAuth 2.0 is an authentication protocol that allows applications to access resources without having to ask the user for their credentials. In this tutorial, we will be using the Google Drive API which requires you to use OAuth 2.0 in order to access it.

It is very common to have a web application that needs to access a Google API like Youtube, Google Drive, or any other.

It is very common to have a web application that needs to access a Google API like Youtube, Google Drive, or any other. The Google OAuth 2.0 is the standard way to do this. In this tutorial we will see how to use it in Python using the PyGithub library.

Let’s start with an example:

One of the ways to do this is by using the Google OAuth 2.0.

One of the ways to do this is by using the Google OAuth 2.0. OAuth 2.0 is an authorization framework that provides a method for web applications to access data on behalf of a resource owner while providing the resource owner with control over how their information is shared.

OAuth 2.0 is also a protocol for authorization and not just a specification like HTTP or JSON (JavaScript Object Notation). The protocol describes how clients can request permission from servers, called “authorization servers.” Once authorized, clients can access resources which might be stored by those servers or other third-parties called “resource servers.”

In my case, I am going to use the Google Drive API to upload and download files from my application.

In my case, I am going to use the Google Drive API to upload and download files from my application. You will need to create a client ID and server key authorization file before we start. I am also going to use the Google OAuth 2.0 to access Google APIs because it is secure, simple, and powerful way of authentication that allows users to share information without having direct access to their credentials in your app (like passwords).

To get started with this tutorial you will need an existing project with Android Studio.

To get started with this tutorial you will need an existing project with Android Studio. You can use any version of Android Studio, but if you don’t have one yet, download it here.

The first step is to create the client ID for your application on Google Developers Console: https://console.developers.google.com/iam-console

The first step is to create the client ID for your application on Google Developers Console: https://console.developers.google.com/iam-console

You can do this by following these steps:

• Click on Credentials > Create credentials > API key (if you don’t have any API keys yet) or OAuth 2.0 credentials > Create new Client ID
• Enter a name for your application, select Web Application as its type and then click on Create button at bottom right corner of page:

Now that you have created and obtained a client ID, you will also need to request a server key authorization file from Google which will be used by your Android application as well as server-side code in order for them to communicate with each other without having to send any credentials over HTTP (like password or username).

In order to get a server key authorization file from google, you’ll need to create an OAuth 2.0 client with access to the Google APIs that you want to use. You can do this by following the steps below:

• Go to https://console.developers.google.com/apis and click on the “Enable API“ button for each of the APIs that you want access too (you may need multiple keys if using multiple APIs).
• Once all of your APIs have been enabled, click on “Credentials“ from the left menu bar at the top of the screen then select the “Create New Client ID“ option from a drop-down list presented before clicking on the “Next Step” button which will bring up the another popup window where you’ll need select `Google API` under `What would you like this application’s credentials?`.

Create a new Java class called AuthClient and add the following code inside it :

You will need to create a new Java class called AuthClient and add the following code inside it:

• import android. app.Activity;
• import android. content.Context;
• import android.util.Log;
• import com.google.android.gms.auth.oauth2.*;

This is how you can use Google OAuth 2.0 to access Google APIs with a refresh token.

Certainly! Here’s a step-by-step guide on how to use Google OAuth 2.0 to access Google APIs with a refresh token:

1. Start by creating a new project in the Google Cloud Platform Console:
   • Go to the Google Cloud Console (console.cloud.google.com).
   • Click on the project drop-down and select “New Project”.
   • Follow the prompts to create a new project, giving it a name and selecting the desired organization.
   • Once created, select the newly created project from the project drop-down.
2. Enable the necessary API(s) for your project:
   • In the Cloud Console, click on “APIs & Services” in the left navigation menu.
   • Click on “Library” and search for the API(s) you want to access.
   • Enable the desired API(s) by clicking on their respective toggle buttons.
3. Set up OAuth consent screen:
   • In the Cloud Console, click on “OAuth consent screen” in the left navigation menu.
   • Choose whether to configure the consent screen for internal or external users.
   • Fill in the required details such as the application name and authorized domains.
   • Save the consent screen configuration.
4. Create OAuth client credentials:
   • In the Cloud Console, click on “Credentials” in the left navigation menu.
   • Click on “Create Credentials” and select “OAuth client ID”.
   • Choose the application type (e.g., Web application, Desktop application).
   • Enter the necessary details such as the redirect URIs and authorized JavaScript origins.
   • Click “Create” to generate the OAuth client ID and client secret.
5. Obtain the authorization code and exchange it for a refresh token and access token:
   • Construct the authorization URL by combining the OAuth authorization endpoint with the required parameters (e.g., client ID, scope, redirect URI).
   • Redirect the user to the authorization URL.
   • After the user grants consent, they will be redirected to the specified redirect URI with an authorization code as a URL parameter.
   • Use the authorization code to make a POST request to the token endpoint, providing the necessary parameters (e.g., authorization code, client ID, client secret, redirect URI).
   • The response will include a refresh token and an access token.
6. Store the refresh token securely:
   • Save the refresh token in a secure location as it will be used to obtain new access tokens.
7. Use the refresh token to obtain new access tokens:
   • When the access token expires, make a POST request to the token endpoint, providing the refresh token, client ID, client secret, and grant type “refresh_token”.
   • The response will include a new access token.
8. Access Google APIs using the access token:
   • Include the access token in the headers of your API requests using the “Authorization” header with the value “Bearer ” followed by the access token.
   • Make the API requests to the desired Google API endpoints, including any required scopes and parameters.

That’s it! You have successfully used Google OAuth 2.0 to access Google APIs with a refresh token. Remember to follow the Google API guidelines and documentation for specific API requirements and limitations. If you need further assistance, feel free to ask!

FAQ

1. What is Google OAuth 2.0?
   • Google OAuth 2.0 is a standard protocol that allows users to grant applications access to Google services without sharing their username and password.
2. What is a refresh token?
   • A refresh token is a special type of token used to obtain a new access token without requiring the user to log in again.
3. What is the purpose of using OAuth 2.0 with Google APIs?
   • Using OAuth 2.0 with Google APIs allows your application to access user data stored in Google services without requiring the user to share their login credentials.
4. How do I obtain an authorization code?
   • To obtain an authorization code, you need to construct an authorization URL by combining the OAuth authorization endpoint with the required parameters (e.g., client ID, scope, redirect URI) and redirect the user to the URL. Once the user grants consent, they will be redirected to the specified redirect URI with an authorization code as a URL parameter.
5. How do I use a refresh token to obtain a new access token?
   • To use a refresh token to obtain a new access token, you need to make a POST request to the token endpoint, providing the refresh token, client ID, client secret, and grant type “refresh_token”. The response will include a new access token.
6. How long does an access token last?
   • By default, access tokens expire after 3600 seconds (1 hour), but the exact expiry time may vary depending on the specific API being used.
7. Do I need to obtain a new authorization code each time I need a new access token?
   • No. Once you have obtained an authorization code and a refresh token, you can use the refresh token to obtain new access tokens without requiring the user to log in again.
8. Can I use the same refresh token across multiple user accounts?
   • No. Refresh tokens are tied to a specific user account and cannot be used across multiple accounts.
9. What happens if my refresh token is revoked or expires?
   • If your refresh token is revoked or has expired, you will need to obtain a new authorization code and exchange it for a new refresh token and access token.
10. Is it safe to store refresh tokens?

• Yes, it is generally safe to store refresh tokens as long as you take appropriate security measures such as encrypting and storing them securely. However, you should be aware that storing refresh tokens carries some risk as they can be used to obtain new access tokens without requiring the user to log in again.