how-to-setup-oauthclient.md

How to setup a a custom Google OAuth2 client for gas, from A to Z

[1] Creating a Google Cloud project

• Go to https://console.cloud.google.com/projectcreate to create a project
• Pick a 'Project name' (e.g. 'MyGasApp')
• Click 'Create'

[2] Setup Oauth consent screen

• Go to the 'Oauth consent screen'-tab
• Fill in a 'Product name shown to users' (e.g 'Gas')

All other fields are optional. (https://raw.githubusercontent.com/MaartenDesnouck/google-apps-script/master/images/logo/gas-logo.png, might be a good 'Product logo URL')

• Click 'Save'

[3] Create API credentials

• Go to the 'Credentials'-tab
• Click 'Create credentials'
• Click 'OAuth client ID'

• Pick 'Web application'
• Fill in a 'Name' for the set of credentials you are creating (e.g. gas-credentials-v1)
• Add 'http://localhost' to the 'Authorized JavaScript origins'
• Add 'http://localhost' to the 'Authorized redirect URIs'
• Click 'Create'

You will get a pop-up with some keys, don't close this pop-up but go to step [4]

[4] Configuring gas to use your credentials

• Go to your terminal
• Run 'gas config'
• Answer the question if you want to use .gs as default extension ('n' will keep the default extension)
• Answer 'y' to the question if you want to use a custom OAuth 2.0 client
• Paste the client ID from the pop-up
• Paste the 'client secret' from the pop-up
  You should see 'Succesfully configured gas [✔]'
• Run 'gas auth'
• You should be redirected to approve your new credentials to make API requests to your Google Drive