flink-python/pyflink/fn_execution/datastream/embedded/side_output_context.py

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#  to you under the Apache License, Version 2.0 (the
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#      http://www.apache.org/licenses/LICENSE-2.0
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from typing import Dict

from pyflink.fn_execution.embedded.converters import from_type_info_proto, DataConverter


class SideOutputContext(object):
    def __init__(self, j_side_output_context):
        self._j_side_output_context = j_side_output_context
        self._side_output_converters = (
            {tag_id: from_type_info_proto(_parse_type_info_proto(payload))
             for tag_id, payload in
             j_side_output_context.getAllSideOutputTypeInfoPayloads().items()}
        )  # type: Dict[str, DataConverter]

    def collect(self, tag_id: str, record):
        try:
            self._j_side_output_context.collectSideOutputById(
                tag_id,
                self._side_output_converters[tag_id].to_external(record))
        except KeyError:
            raise Exception("Unknown OutputTag id {0}, supported OutputTag ids are {1}".format(
                tag_id, list(self._side_output_converters.keys())))


def _parse_type_info_proto(type_info_payload):
    from pyflink.fn_execution import flink_fn_execution_pb2

    type_info = flink_fn_execution_pb2.TypeInfo()
    type_info.ParseFromString(type_info_payload)
    return type_info