airflow/sensors/filesystem.py

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from __future__ import annotations

import datetime
import os
from glob import glob
from typing import Sequence

from airflow.hooks.filesystem import FSHook
from airflow.sensors.base import BaseSensorOperator
from airflow.utils.context import Context


class FileSensor(BaseSensorOperator):
    """
    Waits for a file or folder to land in a filesystem.

    If the path given is a directory then this sensor will only return true if
    any files exist inside it (either directly, or within a subdirectory)

    :param fs_conn_id: reference to the File (path)
        connection id
    :param filepath: File or folder name (relative to
        the base path set within the connection), can be a glob.
    :param recursive: when set to ``True``, enables recursive directory matching behavior of
        ``**`` in glob filepath parameter. Defaults to ``False``.

    .. seealso::
        For more information on how to use this sensor, take a look at the guide:
        :ref:`howto/operator:FileSensor`


    """

    template_fields: Sequence[str] = ("filepath",)
    ui_color = "#91818a"

    def __init__(self, *, filepath, fs_conn_id="fs_default", recursive=False, **kwargs):
        super().__init__(**kwargs)
        self.filepath = filepath
        self.fs_conn_id = fs_conn_id
        self.recursive = recursive

    def poke(self, context: Context):
        hook = FSHook(self.fs_conn_id)
        basepath = hook.get_path()
        full_path = os.path.join(basepath, self.filepath)
        self.log.info("Poking for file %s", full_path)

        for path in glob(full_path, recursive=self.recursive):
            if os.path.isfile(path):
                mod_time = datetime.datetime.fromtimestamp(os.path.getmtime(path)).strftime("%Y%m%d%H%M%S")
                self.log.info("Found File %s last modified: %s", str(path), mod_time)
                return True

            for _, _, files in os.walk(path):
                if len(files) > 0:
                    return True
        return False