I’m currently building a website called EduInsights for my college to manage the semester results. I want access to the drive and sheets API provided by Google to export the results to a spreadsheet and also to extract results from PDFs in a drive folder. In the GCP console I’ve created the credentials and downloaded it as a .json file. When I authorise my application the first time and generate the token in a token.json file, after few days the token gets expired and I have to delete the file and re-authtorise.