github.com/apache/beam/sdks/v2@v2.48.2/python/apache_beam/testing/benchmarks/nexmark/queries/query0.py (about)

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    17  
    18  """Nexmark Query 0: Pass through (send and receive auction events).
    19  
    20  The Nexmark suite is a series of queries (streaming pipelines) performed
    21  on a simulation of auction events.
    22  
    23  This query is a pass through that
    24  simply parses the events generated by the launcher. It serves as a test
    25  to verify the infrastructure.
    26  """
    27  
    28  # pytype: skip-file
    29  
    30  import apache_beam as beam
    31  
    32  
    33  class RoundTripFn(beam.DoFn):
    34    def process(self, element):
    35      coder = element.CODER
    36      byte_value = coder.encode(element)
    37      recon = coder.decode(byte_value)
    38      yield recon
    39  
    40  
    41  def load(events, metadata=None, pipeline_options=None):
    42    return (
    43        events
    44        | 'serialization_and_deserialization' >> beam.ParDo(RoundTripFn()))