This describes how to authenticate with Google Datastore using Goa, and opting out of automatic refreshing, as described in Oauth2 for Apps Script in a few lines of code (which you should read first for background).
The library, cGoa, is available under this project key, or on github. All the tests described for this topic are also available on github.
In Accessing as the user running the script I described how to generate separate token packages for each user running the script, mainly for webapps published like this.
Once authorized this pattern will store an individual refresh token for each user in their UserProperties so that in future, access can be made without the need to re-authorize through the OAuth2 dialog. Users can opt out of this through this check box in the consent screen.
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Learning Apps Script, (and transitioning from VBA) are covered comprehensively in my my book, Going Gas - from VBA to Apps script, All formats are available from O'Reilly, Amazon and all good bookshops. You can also read a preview on O'Reilly
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