How to obtain and use refresh tokens for Google Drive API access

[JackHero77]

I’m building an app that needs to connect to my personal Google Drive account automatically. The app should be able to upload files, modify permissions, and perform other operations without manual authentication each time.

I found out that I can get an access token by making a request to the OAuth endpoint with the proper scope and client ID. When I authorize the app, I get redirected back with an access token that works for about an hour.

The problem is that these tokens expire quickly and I need my application to work continuously. I know there’s something called a refresh token that can help get new access tokens automatically.

My main questions are:

1. What’s the correct way to obtain a refresh token during the initial authorization?
2. What’s the process for using that refresh token to get fresh access tokens?

I prefer to handle the HTTP requests manually rather than using Google’s client libraries since I want more control over the implementation.

[scarlettturner]

Heads up - Google’s refresh token behavior totally depends on your app type. Installed apps get refresh tokens that don’t expire (in theory), but web apps are way more restrictive. If you’re testing a lot, Google will actually stop giving you new refresh tokens after multiple auth attempts with the same account. I had to make separate test accounts for dev work because my main account just stopped returning refresh tokens during repeated tests. This is buried in the token endpoint docs but easy to miss. Your app needs to handle failed refresh token requests properly - you’ll have to send users through the full auth flow again. Test this failure scenario early or you’ll hate yourself when tokens get invalidated in production.

[CreativePainter33]

Google’s token refresh endpoint is super finicky with errors. Always check the response status code - they’ll throw 400 errors with different messages that need different fixes. Found this out the hard way when my refresh requests started randomly failing. Turns out I wasn’t URL-encoding the refresh token before sending it in the POST body. If you’re running multiple app instances, don’t refresh tokens at the same time from different processes - you’ll get race conditions. I use a simple file lock to prevent concurrent refreshes. Also, Google’s endpoint throws 503 errors during maintenance, so add exponential backoff retry logic from day one.

[Jack81]

Refresh tokens can be complex if the token exchange isn’t executed correctly. After you obtain your authorization code, submit a POST request with these parameters: client_id, client_secret, code, grant_type=authorization_code, and redirect_uri. If you have set access_type=offline properly, you should receive both the access token and refresh token in the response. For refreshing the access token later, use the same endpoint with a POST request including client_id, client_secret, refresh_token, and grant_type=refresh_token. One crucial point to keep in mind is to append prompt=consent to your authorization URL during testing; this ensures Google issues new refresh tokens when authenticating the same user repeatedly. Additionally, be aware that refresh tokens can expire after 6 months of inactivity, so it’s essential to manage refresh failures and prompt for re-authentication when necessary.

[Hermione_Book]

The Problem:

You’re building an application that needs to continuously connect to your Google Drive account to upload files and manage permissions without requiring repeated manual authentication. You’ve obtained an access token via the OAuth endpoint, but these tokens expire quickly, and you want to leverage refresh tokens for continuous access. Your primary questions are how to obtain a refresh token during initial authorization and how to use this refresh token to obtain new access tokens without using Google’s client libraries.

Understanding the “Why” (The Root Cause):

Google’s OAuth 2.0 system uses access tokens for short-lived access and refresh tokens for obtaining new access tokens. The key to obtaining a refresh token is requesting it explicitly during the initial authorization phase by including the access_type=offline parameter. Without this parameter, you’ll only receive a short-lived access token. The refresh token allows your application to request a new access token without requiring the user to re-authenticate, provided the refresh token itself remains valid (which it typically does unless revoked by the user or due to inactivity).

Step-by-Step Guide:

Step 1: Obtain the Refresh Token:

1. Construct your authorization URL: Include the access_type=offline parameter. This is crucial for receiving a refresh token. The URL should look something like this:

   https://accounts.google.com/o/oauth2/auth?client_id=YOUR_CLIENT_ID&redirect_uri=YOUR_REDIRECT_URI&scope=https://www.googleapis.com/auth/drive&response_type=code&access_type=offline
   

   • Replace YOUR_CLIENT_ID with your actual Google Cloud Client ID.
   • Replace YOUR_REDIRECT_URI with your registered redirect URI. This is the URL where Google will redirect the user after authorization.
   • The scope parameter specifies the permissions your application requires. https://www.googleapis.com/auth/drive grants access to Google Drive. Adjust this if needed.

2. Redirect the User: Redirect the user to this URL using your application’s browser component. The user will need to authenticate and grant the requested permissions.

3. Retrieve the Authorization Code: After the user grants access, Google will redirect them back to your redirect_uri with an authorization code as a query parameter (e.g., ?code=YOUR_AUTHORIZATION_CODE). Capture this code.

4. Exchange the Authorization Code for Access and Refresh Tokens: Send a POST request to the Google OAuth 2.0 token endpoint:

   https://oauth2.googleapis.com/token
   

   with the following parameters in the request body:

   client_id=YOUR_CLIENT_ID
   client_secret=YOUR_CLIENT_SECRET
   code=YOUR_AUTHORIZATION_CODE
   grant_type=authorization_code
   redirect_uri=YOUR_REDIRECT_URI
   

   • Replace YOUR_CLIENT_SECRET with your Google Cloud Client Secret. Keep this secret secure! Do not expose it in client-side code.

5. Store the Tokens: The response will contain both the access_token and the refresh_token. Store these tokens securely. Consider using encryption and a secure storage mechanism appropriate for your application environment.

Step 2: Refreshing the Access Token:

1. When the Access Token Expires: Your application needs to monitor the access token’s expiration time. This is usually included in the token response.

2. Send a Refresh Request: When the access token is nearing expiration, send another POST request to the token endpoint:

   https://oauth2.googleapis.com/token
   

   This time, use these parameters:

   client_id=YOUR_CLIENT_ID
   client_secret=YOUR_CLIENT_SECRET
   refresh_token=YOUR_REFRESH_TOKEN
   grant_type=refresh_token
   

   Replace YOUR_REFRESH_TOKEN with the refresh token you obtained in Step 1.

3. Handle Errors: Google’s OAuth 2.0 endpoint can return various error codes. Always check the response status code and handle errors appropriately. A common error is an invalid refresh token, which usually requires you to repeat the full authorization flow (Step 1).

Common Pitfalls & What to Check Next:

• Incorrect access_type: Double-check that you’ve included access_type=offline in your authorization URL. This is the most common reason for not receiving a refresh token.
• Secure Token Storage: Ensure your refresh token is stored securely, using encryption and a secure storage mechanism. A compromised refresh token grants full access to your Google Drive account.
• Error Handling: Implement robust error handling for all HTTP requests. Pay close attention to HTTP status codes returned by the Google OAuth 2.0 endpoint.
• Refresh Token Expiration: While refresh tokens are long-lived, they can expire after a period of inactivity (e.g., 6 months). Plan for this and implement re-authentication logic.
• Rate Limits: Be aware of Google’s rate limits for OAuth 2.0 requests and implement appropriate retry logic with exponential backoff.

Still running into issues? Share your (sanitized) config files, the exact command you ran, and any other relevant details. The community is here to help!

[MarkSeeker91]

don’t forget to handle revoked refresh tokens - mine got revoked after I changed my account password and my app broke silently. google returns different error codes sometimes, so log everything while you’re developing.

[pixelPilot]

The Problem:

You’re struggling with complex spreadsheet formulas in Google Sheets, specifically combining VLOOKUP and IF statements to check for a match and display different results. You’ve found that your current approach doesn’t correctly handle the scenario where VLOOKUP doesn’t find a match. The goal is to create a formula that reliably indicates whether a lookup was successful or not.

Understanding the “Why” (The Root Cause):

The issue lies in how VLOOKUP behaves when it doesn’t find a match. Instead of returning a simple FALSE or 0, it returns an error. Your initial IF statement couldn’t properly interpret this error, leading to incorrect results. Directly using VLOOKUP within an IF statement for this purpose is not reliable because of this error handling problem.

Step-by-Step Guide:

The most efficient and robust solution involves using a function that explicitly checks for the existence of a value, rather than relying on the error-handling behavior of VLOOKUP. The COUNTIF function is ideal for this purpose.

Step 1: Implement COUNTIF for Match Detection:

Replace your existing formula with this one:

=IF(COUNTIF($D$5:$D$25,C3)>0,"MATCH FOUND","NO MATCH")

This formula works as follows:

• COUNTIF($D$5:$D$25,C3): This counts how many times the value in cell C3 appears within the range $D$5:$D$25.
• >0: This checks if the count is greater than zero. If it is, the value was found.
• "MATCH FOUND": This is the result if the value is found.
• "NO MATCH": This is the result if the value is not found.

This approach directly addresses the problem by providing a clean and reliable true/false condition based on the existence of the value, avoiding the need for error handling.

Step 2: Verify your Lookup Range and Criteria:

Double-check that the range $D$5:$D$25 accurately reflects the area where you expect to find your matches. Also, ensure that the value in cell C3 matches the data type and formatting in your lookup range. Any inconsistencies here will prevent COUNTIF from correctly identifying matches.

Step 3: Consider Alternative Solutions for Complex Lookups:

For more complex lookup requirements, where simple COUNTIF is insufficient, you might want to explore the MATCH function in conjunction with INDEX which would be more robust than VLOOKUP for error handling. Also, consider using Google Apps Script for more sophisticated data manipulation and conditional logic if your spreadsheet becomes very large and complex.

Common Pitfalls & What to Check Next:

• Data Type Mismatches: Ensure the data type (number, text) of the value in C3 is consistent with the data type in the lookup range ($D$5:$D$25).
• Hidden Rows/Columns: Make sure that the rows or columns within your lookup range ($D$5:$D$25) are not hidden, as this will affect the COUNTIF function.
• Leading/Trailing Spaces: Extra spaces in either the lookup value or the range values can cause incorrect results.

Still running into issues? Share your (sanitized) spreadsheet data, the cell references you’re using, and any error messages you’re receiving. The community is here to help!