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