What would you like to happen?

Currently BigQueryIO.Read can't be put behind impulse which forces developers to use bigquery client library to directly interact with BigQuery when they need to perodically refresh data.

Python SDK has such functionality. example:

  side_input = (
      p
      | 'PeriodicImpulse' >> PeriodicImpulse(
          first_timestamp, last_timestamp, interval, True)
      | 'MapToReadRequest' >> beam.Map(
          lambda x: ReadFromBigQueryRequest(table='dataset.table'))
      | beam.io.ReadAllFromBigQuery())

Issue Priority

Priority: 2 (default / most feature requests should be filed as P2)

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