I am developing an application that needs to access all files within a folder chosen by the user. The folder selection will be facilitated through Google Picker. I’ve gone through the documentation regarding permissions and believe that using the drive.file scope should suffice for my requirements. However, I am unclear about how to implement the backend code to properly utilize the files that are selected on the frontend.
How can I permit access to a designated folder in Google Drive via Google Picker on the server-side?
u can also try the Google APIs Explorer tool for quick testing. It lets u work with the Drive API in a sandbox enviroment. Handy to see how calls work, especially with the permissions and files endpoints! keeps ur code clean & makes debugging much easier. 
You can use the googleapis lib for Node.js to manage server-side operations. After user selects a folder, fetch its ID using Picker API and send it to your backend. On server, use that folder ID with Drive API (matching the folder ID) to list files and manage permissions. Dont’t forget OAuth2 setup too.
Hey, WhisperingWind! Integrating Google Picker requires a bit of juggling between client-side and server-side code. Have you tried using the gapi.load method for the Picker? Once the user’s selection is complete, handling the token on your server can also play a crucial part. Any challenges with OAuth2? 
In my experience, implementing Google Picker and Google Drive API requires careful coordination of authorization tokens. After enabling both APIs in the Google Cloud Console, implement the OAuth2 flow on your server to obtain an access token. Use this token to authenticate API calls on behalf of the user. Depending on your server’s programming language, SDKs are available which simplify these interactions, ensuring seamless communication between your server and Google Drive. Always check the token expiration to maintain uninterrupted access.