Source code for airflow.providers.apache.kafka.hooks.consume

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from __future__ import annotations

from collections.abc import Sequence

from confluent_kafka import Consumer, KafkaError

from airflow.providers.apache.kafka.hooks.base import KafkaBaseHook
from airflow.utils.module_loading import import_string


[docs]class KafkaAuthenticationError(Exception):
    """Custom exception for Kafka authentication failures."""

    pass


[docs]def error_callback(err):
    """Handle kafka errors."""
    if err.code() == KafkaError._AUTHENTICATION:
        raise KafkaAuthenticationError(f"Authentication failed: {err}")
    print("Exception received: ", err)


[docs]class KafkaConsumerHook(KafkaBaseHook):
    """
    A hook for creating a Kafka Consumer.

    :param kafka_config_id: The connection object to use, defaults to "kafka_default"
    :param topics: A list of topics to subscribe to.
    """

    def __init__(self, topics: Sequence[str], kafka_config_id=KafkaBaseHook.default_conn_name) -> None:
        super().__init__(kafka_config_id=kafka_config_id)
        self.topics = topics

    def _get_client(self, config) -> Consumer:
        config_shallow = config.copy()
        if config.get("error_cb") is None:
            config_shallow["error_cb"] = error_callback
        else:
            config_shallow["error_cb"] = import_string(config["error_cb"])
        return Consumer(config_shallow)

[docs]    def get_consumer(self) -> Consumer:
        """Return a Consumer that has been subscribed to topics."""
        consumer = self.get_conn
        consumer.subscribe(self.topics)

        return consumer