Source code for airflow.providers.apache.hdfs.sensors.web_hdfs

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# 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
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#   http://www.apache.org/licenses/LICENSE-2.0
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from __future__ import annotations

from collections.abc import Sequence
from typing import TYPE_CHECKING, Any

from airflow.sensors.base import BaseSensorOperator

if TYPE_CHECKING:
    from hdfs import InsecureClient
    from hdfs.ext.kerberos import KerberosClient

    from airflow.utils.context import Context



[docs]
class WebHdfsSensor(BaseSensorOperator):
    """Waits for a file or folder to land in HDFS."""


[docs]
    template_fields: Sequence[str] = ("filepath",)


    def __init__(self, *, filepath: str, webhdfs_conn_id: str = "webhdfs_default", **kwargs: Any) -> None:
        super().__init__(**kwargs)

[docs]
        self.filepath = filepath


[docs]
        self.webhdfs_conn_id = webhdfs_conn_id



[docs]
    def poke(self, context: Context) -> bool:
        from airflow.providers.apache.hdfs.hooks.webhdfs import WebHDFSHook

        hook = WebHDFSHook(self.webhdfs_conn_id)
        self.log.info("Poking for file %s", self.filepath)
        return hook.check_for_path(hdfs_path=self.filepath)





[docs]
class MultipleFilesWebHdfsSensor(BaseSensorOperator):
    """Waits for multiple files in a folder to land in HDFS."""


[docs]
    template_fields: Sequence[str] = ("directory_path", "expected_filenames")


    def __init__(
        self,
        *,
        directory_path: str,
        expected_filenames: Sequence[str],
        webhdfs_conn_id: str = "webhdfs_default",
        **kwargs: Any,
    ) -> None:
        super().__init__(**kwargs)

[docs]
        self.directory_path = directory_path


[docs]
        self.expected_filenames = expected_filenames


[docs]
        self.webhdfs_conn_id = webhdfs_conn_id



[docs]
    def poke(self, context: Context) -> bool:
        from airflow.providers.apache.hdfs.hooks.webhdfs import WebHDFSHook

        hook = WebHDFSHook(self.webhdfs_conn_id)
        conn: KerberosClient | InsecureClient = hook.get_conn()

        actual_files = set(conn.list(self.directory_path))
        self.log.debug("Files Found in directory: %s", actual_files)

        missing_files = set(self.expected_filenames) - actual_files
        if missing_files:
            self.log.info("There are missing files: %s", missing_files)
            return False
        return True