I have implemented an oauth2 flow in my frontend and I am storing user credentials in my backend, like this:

export type Credentials = {
    refresh_token: string;
    expiry_date: number;
    access_token: string;
    token_type: string;
    id_token: string;
    scope: string;
}

I want to connect to BQ on behalf of the user but there is no way to plugin in Oauth2 credentials, only a service account apparently.

This doesn’t work despite being suggested in some places:

import { BigQuery } from "@google-cloud/bigquery";

    const bigquery = new BigQuery({
        credentials: { access_token: accessToken },
    });

The idea is that the user can connect to multiple projects, not just one, so I don’t want to create a SA for each project. Just like when you access the BQ interface, you don’t have a SA per project.

Am I missing something?
Thanks!