Issue

When trying to add a BigQuery connection in web authoring (Desktop or Prep), the following error may occur:

Custom OAuth is not configured for this datasource. Lean more. (errorCode=170001)

Additionally, when publishing a flow that uses a Google BigQuery data source to Tableau Server, the only data source authentication option available is 'Prompt user', and the option to edit the BigQuery connection is unavailable in Tableau Server. Running the published flow may result in the following output step error message: 

[InvalidConnectionCredentials] - Failed to connect to server <server id> with connection ID . The provided username/password combination was invalid.