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

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from __future__ import annotations

from typing import TYPE_CHECKING, Any, Sequence

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)
        self.filepath = filepath
        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)
        self.directory_path = directory_path
        self.expected_filenames = expected_filenames
        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