airflow/jobs/dag_processor_job_runner.py

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# distributed with this work for additional information
# regarding copyright ownership.  The ASF licenses this file
# to you under the Apache License, Version 2.0 (the
# "License"); you may not use this file except in compliance
# with the License.  You may obtain a copy of the License at
#
#   http://www.apache.org/licenses/LICENSE-2.0
#
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# KIND, either express or implied.  See the License for the
# specific language governing permissions and limitations
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from __future__ import annotations

from typing import Any

from airflow.dag_processing.manager import DagFileProcessorManager
from airflow.jobs.base_job_runner import BaseJobRunner
from airflow.jobs.job import Job, perform_heartbeat
from airflow.utils.log.logging_mixin import LoggingMixin


def empty_callback(_: Any) -> None:
    pass


class DagProcessorJobRunner(BaseJobRunner[Job], LoggingMixin):
    """
    DagProcessorJobRunner is a job runner that runs a DagFileProcessorManager processor.

    :param job: Job instance to use
    :param processor: DagFileProcessorManager instance to use
    """

    job_type = "DagProcessorJob"

    def __init__(
        self,
        job: Job,
        processor: DagFileProcessorManager,
        *args,
        **kwargs,
    ):
        super().__init__(job)
        self.processor = processor
        self.processor.heartbeat = lambda: perform_heartbeat(
            job=self.job,
            heartbeat_callback=empty_callback,
            only_if_necessary=True,
        )

    def _execute(self) -> int | None:
        self.log.info("Starting the Dag Processor Job")
        try:
            self.processor.start()
        except Exception:
            self.log.exception("Exception when executing DagProcessorJob")
            raise
        finally:
            self.processor.terminate()
            self.processor.end()
        return None