#
# Licensed to the Apache Software Foundation (ASF) under one
# or more contributor license agreements. See the NOTICE file
# distributed with this work for additional information
# regarding copyright ownership. The ASF licenses this file
# 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
#
# http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing,
# software distributed under the License is distributed on an
# "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
# KIND, either express or implied. See the License for the
# specific language governing permissions and limitations
# under the License.
from __future__ import annotations
import logging
import os
import shutil
from functools import cached_property
from pathlib import Path
from typing import TYPE_CHECKING, Collection
# not sure why but mypy complains on missing `storage` but it is clearly there and is importable
from google.cloud import storage # type: ignore[attr-defined]
from airflow.configuration import conf
from airflow.exceptions import AirflowNotFoundException
from airflow.providers.google.cloud.hooks.gcs import GCSHook, _parse_gcs_url
from airflow.providers.google.cloud.utils.credentials_provider import get_credentials_and_project_id
from airflow.providers.google.common.consts import CLIENT_INFO
from airflow.utils.log.file_task_handler import FileTaskHandler
from airflow.utils.log.logging_mixin import LoggingMixin
if TYPE_CHECKING:
from airflow.models.taskinstance import TaskInstance
_DEFAULT_SCOPESS = frozenset(
[
"https://www.googleapis.com/auth/devstorage.read_write",
]
)
[docs]logger = logging.getLogger(__name__)
[docs]class GCSTaskHandler(FileTaskHandler, LoggingMixin):
"""
GCSTaskHandler is a python log handler that handles and reads task instance logs.
It extends airflow FileTaskHandler and uploads to and reads from GCS remote
storage. Upon log reading failure, it reads from host machine's local disk.
:param base_log_folder: Base log folder to place logs.
:param gcs_log_folder: Path to a remote location where logs will be saved. It must have the prefix
``gs://``. For example: ``gs://bucket/remote/log/location``
:param filename_template: template filename string
:param gcp_key_path: Path to Google Cloud Service Account file (JSON). Mutually exclusive with
gcp_keyfile_dict.
If omitted, authorization based on `the Application Default Credentials
<https://cloud.google.com/docs/authentication/production#finding_credentials_automatically>`__ will
be used.
:param gcp_keyfile_dict: Dictionary of keyfile parameters. Mutually exclusive with gcp_key_path.
:param gcp_scopes: Comma-separated string containing OAuth2 scopes
:param project_id: Project ID to read the secrets from. If not passed, the project ID from credentials
will be used.
:param delete_local_copy: Whether local log files should be deleted after they are downloaded when using
remote logging
"""
[docs] trigger_should_wrap = True
def __init__(
self,
*,
base_log_folder: str,
gcs_log_folder: str,
filename_template: str | None = None,
gcp_key_path: str | None = None,
gcp_keyfile_dict: dict | None = None,
gcp_scopes: Collection[str] | None = _DEFAULT_SCOPESS,
project_id: str | None = None,
**kwargs,
):
super().__init__(base_log_folder, filename_template)
self.handler: logging.FileHandler | None = None
self.remote_base = gcs_log_folder
self.log_relative_path = ""
self.closed = False
self.upload_on_close = True
self.gcp_key_path = gcp_key_path
self.gcp_keyfile_dict = gcp_keyfile_dict
self.scopes = gcp_scopes
self.project_id = project_id
self.delete_local_copy = kwargs.get(
"delete_local_copy", conf.getboolean("logging", "delete_local_logs")
)
@cached_property
[docs] def hook(self) -> GCSHook | None:
"""Returns GCSHook if remote_log_conn_id configured."""
conn_id = conf.get("logging", "remote_log_conn_id", fallback=None)
if conn_id:
try:
return GCSHook(gcp_conn_id=conn_id)
except AirflowNotFoundException:
pass
return None
@cached_property
[docs] def client(self) -> storage.Client:
"""Returns GCS Client."""
if self.hook:
credentials, project_id = self.hook.get_credentials_and_project_id()
else:
credentials, project_id = get_credentials_and_project_id(
key_path=self.gcp_key_path,
keyfile_dict=self.gcp_keyfile_dict,
scopes=self.scopes,
disable_logging=True,
)
return storage.Client(
credentials=credentials,
client_info=CLIENT_INFO,
project=self.project_id if self.project_id else project_id,
)
[docs] def set_context(self, ti: TaskInstance, *, identifier: str | None = None) -> None:
# todo: remove-at-min-airflow-version-2.8
# after Airflow 2.8 can always pass `identifier`
if getattr(super(), "supports_task_context_logging", False):
super().set_context(ti, identifier=identifier)
else:
super().set_context(ti)
# Log relative path is used to construct local and remote
# log path to upload log files into GCS and read from the
# remote location.
if TYPE_CHECKING:
assert self.handler is not None
full_path = self.handler.baseFilename
self.log_relative_path = Path(full_path).relative_to(self.local_base).as_posix()
is_trigger_log_context = getattr(ti, "is_trigger_log_context", False)
self.upload_on_close = is_trigger_log_context or not getattr(ti, "raw", None)
[docs] def close(self):
"""Close and upload local log file to remote storage GCS."""
# When application exit, system shuts down all handlers by
# calling close method. Here we check if logger is already
# closed to prevent uploading the log to remote storage multiple
# times when `logging.shutdown` is called.
if self.closed:
return
super().close()
if not self.upload_on_close:
return
local_loc = os.path.join(self.local_base, self.log_relative_path)
remote_loc = os.path.join(self.remote_base, self.log_relative_path)
if os.path.exists(local_loc):
# read log and remove old logs to get just the latest additions
with open(local_loc) as logfile:
log = logfile.read()
gcs_write = self.gcs_write(log, remote_loc)
if gcs_write and self.delete_local_copy:
shutil.rmtree(os.path.dirname(local_loc))
# Mark closed so we don't double write if close is called twice
self.closed = True
def _add_message(self, msg):
filename, lineno, func, stackinfo = logger.findCaller()
record = logging.LogRecord("", logging.INFO, filename, lineno, msg + "\n", None, None, func=func)
return self.format(record)
def _read_remote_logs(self, ti, try_number, metadata=None) -> tuple[list[str], list[str]]:
# Explicitly getting log relative path is necessary because this method
# is called from webserver from TaskLogReader, where we don't call set_context
# and can read logs for different TIs in each request
messages = []
logs = []
worker_log_relative_path = self._render_filename(ti, try_number)
remote_loc = os.path.join(self.remote_base, worker_log_relative_path)
uris = []
bucket, prefix = _parse_gcs_url(remote_loc)
blobs = list(self.client.list_blobs(bucket_or_name=bucket, prefix=prefix))
if blobs:
uris = [f"gs://{bucket}/{b.name}" for b in blobs]
messages.extend(["Found remote logs:", *[f" * {x}" for x in sorted(uris)]])
else:
messages.append(f"No logs found in GCS; ti=%s {ti}")
try:
for key in sorted(uris):
blob = storage.Blob.from_string(key, self.client)
remote_log = blob.download_as_bytes().decode()
if remote_log:
logs.append(remote_log)
except Exception as e:
messages.append(f"Unable to read remote log {e}")
return messages, logs
[docs] def gcs_write(self, log, remote_log_location) -> bool:
"""
Write the log to the remote location and return `True`; fail silently and return `False` on error.
:param log: the log to write to the remote_log_location
:param remote_log_location: the log's location in remote storage
:return: whether the log is successfully written to remote location or not.
"""
try:
blob = storage.Blob.from_string(remote_log_location, self.client)
old_log = blob.download_as_bytes().decode()
log = f"{old_log}\n{log}" if old_log else log
except Exception as e:
if not self.no_log_found(e):
log += self._add_message(
f"Error checking for previous log; if exists, may be overwritten: {e}"
)
self.log.warning("Error checking for previous log: %s", e)
try:
blob = storage.Blob.from_string(remote_log_location, self.client)
blob.upload_from_string(log, content_type="text/plain")
except Exception as e:
self.log.error("Could not write logs to %s: %s", remote_log_location, e)
return False
return True
@staticmethod
def no_log_found(exc):
"""
Given exception, determine whether it is result of log not found.
:meta private:
"""
if (exc.args and isinstance(exc.args[0], str) and "No such object" in exc.args[0]) or getattr(
exc, "resp", {}
).get("status") == "404":
return True
return False
