ashb commented on code in PR #43893: URL: https://github.com/apache/airflow/pull/43893#discussion_r1837963326
########## task_sdk/src/airflow/sdk/execution_time/task_runner.py: ########## @@ -0,0 +1,195 @@ +# +# 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. +"""The entrypoint for the actual task execution process.""" + +from __future__ import annotations + +import os +import sys +from io import FileIO +from typing import TYPE_CHECKING, TextIO + +import attrs +import msgspec +import structlog + +from airflow.sdk import BaseOperator +from airflow.sdk.execution_time.comms import StartupDetails, TaskInstance, ToSupervisor, ToTask + +if TYPE_CHECKING: + from structlog.typing import FilteringBoundLogger as Logger + + +class RuntimeTaskInstance(TaskInstance, kw_only=True): + task: BaseOperator + + +def parse(what: StartupDetails) -> RuntimeTaskInstance: + # TODO: Task-SDK: + # Using DagBag here is aoubt 98% wrong, but it'll do for now + + from airflow.models.dagbag import DagBag + + bag = DagBag( + dag_folder=what.file, + include_examples=False, + safe_mode=False, + load_op_links=False, + ) + if TYPE_CHECKING: + assert what.ti.dag_id + + dag = bag.dags[what.ti.dag_id] + + # install_loader() + + # TODO: Handle task not found + task = dag.task_dict[what.ti.task_id] + if not isinstance(task, BaseOperator): + raise TypeError(f"task is of the wrong type, got {type(task)}, wanted {BaseOperator}") + return RuntimeTaskInstance(**msgspec.structs.asdict(what.ti), task=task) + + [email protected]() +class CommsDecoder: + """Handle communication between the task in this process and the supervisor parent process.""" + + input: TextIO = sys.stdin + + decoder: msgspec.json.Decoder[ToTask] = attrs.field(factory=lambda: msgspec.json.Decoder(type=ToTask)) + encoder: msgspec.json.Encoder = attrs.field(factory=msgspec.json.Encoder) + + request_socket: FileIO = attrs.field(init=False, default=None) + + # Allocate a buffer for en/decoding. We use a small non-empty buffer to avoid reallocating for small messages. + buffer: bytearray = attrs.field(factory=lambda: bytearray(64)) + + def get_message(self) -> ToTask: + """ + Get a message from the parent. + + This will block until the message has been received. + """ + line = self.input.readline() + try: + msg = self.decoder.decode(line) + except Exception: + structlog.get_logger(logger_name="CommsDecoder").exception("Unable to decode message", line=line) + raise + + if isinstance(msg, StartupDetails): + # If we read a startup message, pull out the FDs we care about! + if msg.requests_fd > 0: + self.request_socket = os.fdopen(msg.requests_fd, "wb", buffering=0) + return msg + + def send_request(self, log: Logger, msg: ToSupervisor): + buffer = self.buffer + self.encoder.encode_into(msg, buffer) + buffer += b"\n" + + log.debug("Sending request", json=buffer) + self.request_socket.write(buffer) + + +# This global variable will be used by Connection/Variable classes etc to send requests to +SUPERVISOR_COMMS: CommsDecoder Review Comment: This runs in the individual task process (forked or subprocess) so there can only ever be one per process. -- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. To unsubscribe, e-mail: [email protected] For queries about this service, please contact Infrastructure at: [email protected]
