nuclearpinguin commented on a change in pull request #7027: [WIP][AIRFLOW-6441] KnativeExecutor URL: https://github.com/apache/airflow/pull/7027#discussion_r363028535
########## File path: airflow/executors/knative_executor.py ########## @@ -0,0 +1,210 @@ +# -*- coding: utf-8 -*- +# +# 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. +""" +This module contains KnativeExecutor which is optimized +for running lots of short tasks in a scalable, efficient manner. +""" + +import asyncio +import datetime +import functools +import multiprocessing + +import aiohttp +from cached_property import cached_property + +from airflow.configuration import conf +from airflow.exceptions import AirflowConfigException, AirflowException +from airflow.executors.base_executor import BaseExecutor +from airflow.executors.kubernetes_executor import KubernetesExecutor +from airflow.utils.log.logging_mixin import LoggingMixin +from airflow.utils.state import State + + +async def make_request_async( + task_id, + dag_id, + execution_date, + host, + log, + host_header=None, +) -> aiohttp.ClientResponse: + """ + + Thius function crafts a request to an external airflow server. This server is assumed to be + a knative service. + @param task_id: + @param dag_id: + @param execution_date: + @param host: + @param log: + @param host_header: + @return: + """ + req = "http://"; + host + "/run" + + date = int(datetime.datetime.timestamp(execution_date)) + params = { + "task_id": task_id, + "dag_id": dag_id, + "execution_date": date, + } + headers = {} + if host_header: + headers["Host"] = host_header + timeout = aiohttp.ClientTimeout(total=60000) + async with aiohttp.ClientSession(timeout=timeout) as session: + async with session.get(url=req, params=params, headers=headers) as resp: + log.info(resp.status) + log.info(await resp.text()) + return resp + + +class KnativeRequestLoop(multiprocessing.Process, LoggingMixin): + """ + + This class asynchronously pulls tasks from the KnativeExecutor and runs them as coroutines using asyncio + + """ + def __init__(self, + task_pipe, + result_pipe, + host_header, + host, + ): + + super().__init__() + self.host = host + self.task_pipe = task_pipe + self.result_pipe = result_pipe + self.host_header = host_header + + def recieve_and_execute(self, loop): + """ + This function receives tasks from task_pipe and executes them in FIFO order. + @param loop: + """ + key = self.task_pipe.recv() + loop.create_task(self.execute_work(key=key)) + + def run(self): + """ + Starts loop and prepares pipe reader. + """ + loop = asyncio.get_event_loop() + loop.add_reader(fd=self.task_pipe, callback=functools.partial(self.recieve_and_execute, loop)) + loop.run_forever() + + async def execute_work(self, key): + """ + Executes command received and stores result state in queue. + :param task_instance: + :param key: the key to identify the TI + :type key: tuple(dag_id, task_id, execution_date) + :param command: the command to execute + :type command: str + """ + if key is None: + return + self.log.info("%s running %s", self.__class__.__name__, key) + (dag_id, task_id, execution_date, _) = key + try: + future = make_request_async( + task_id, + dag_id, + execution_date, + host=self.host, log=self.log, host_header=self.host_header) + resp = await future + if resp.status != 200: + state = State.FAILED + self.log.error("Failed to execute task %s.", str(resp.text)) + self.result_pipe.send((key, state)) + else: + self.log.info("assuming final state has been handled") + self.result_pipe.send((key, None)) + + except asyncio.InvalidStateError as e: + state = State.FAILED + self.log.error("Failed to execute task %s.", str(e)) + self.result_pipe.send((key, state)) + + +class KnativeExecutor(BaseExecutor): + """ + KnativeExecutor executes tasks locally in parallel. It uses the + multiprocessing Python library and queues to parallelize the execution + of tasks. + """ + task_queue = None + result_queue = None + result_pipe = None + + def terminate(self): + pass + + @cached_property + def kube_executor(self) -> KubernetesExecutor: + """ + lazily loads KubernetesExecutor + @return: + """ + self.kube_executor_initialized = True + return KubernetesExecutor() + + def __init__(self): + self.kube_executor_initialized = False + super().__init__() + self.task_pipe = None + self.local_loop = None + + def start(self): + req = conf.get("knative", "knative_host") + try: + host_header = conf.get("knative", "knative_host_header") + except AirflowConfigException: + host_header = None Review comment: ```suggestion host_header = conf.get("knative", "knative_host_header", fallback=None) ``` ---------------------------------------------------------------- This is an automated message from the Apache Git Service. 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