sdks/python/apache_beam/examples/snippets/transforms/aggregation/cogroupbykey.py

# coding=utf-8
#
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#    http://www.apache.org/licenses/LICENSE-2.0
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# pytype: skip-file
# pylint:disable=line-too-long

# beam-playground:
#   name: CoGroupByKeyMerge
#   description: Demonstration of CoGroupByKey transform usage.
#   multifile: false
#   default_example: false
#   context_line: 43
#   categories:
#     - Core Transforms
#     - Joins
#   complexity: BASIC
#   tags:
#     - transforms
#     - strings
#     - integers
#     - tuples
#     - pairs
#     - group


def cogroupbykey(test=None):
  # [START cogroupbykey]
  import apache_beam as beam

  with beam.Pipeline() as pipeline:
    icon_pairs = pipeline | 'Create icons' >> beam.Create([
        ('Apple', '🍎'),
        ('Apple', '🍏'),
        ('Eggplant', '🍆'),
        ('Tomato', '🍅'),
    ])

    duration_pairs = pipeline | 'Create durations' >> beam.Create([
        ('Apple', 'perennial'),
        ('Carrot', 'biennial'),
        ('Tomato', 'perennial'),
        ('Tomato', 'annual'),
    ])

    plants = (({
        'icons': icon_pairs, 'durations': duration_pairs
    })
              | 'Merge' >> beam.CoGroupByKey()
              | beam.Map(print))
    # [END cogroupbykey]
    if test:
      test(plants)


if __name__ == '__main__':
  cogroupbykey()