riteshghorse commented on code in PR #30001: URL: https://github.com/apache/beam/pull/30001#discussion_r1453956063
########## sdks/python/apache_beam/io/requestresponse.py: ########## @@ -0,0 +1,408 @@ +# +# 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. +# + +"""``PTransform`` for reading from and writing to Web APIs.""" +import abc +import concurrent.futures +import contextlib +import logging +import sys +import time +from typing import Generic +from typing import Optional +from typing import TypeVar + +from google.api_core.exceptions import TooManyRequests + +import apache_beam as beam +from apache_beam.io.components.adaptive_throttler import AdaptiveThrottler +from apache_beam.metrics import Metrics +from apache_beam.ml.inference.vertex_ai_inference import MSEC_TO_SEC +from apache_beam.utils import retry + +RequestT = TypeVar('RequestT') +ResponseT = TypeVar('ResponseT') + +DEFAULT_TIMEOUT_SECS = 30 # seconds + +_LOGGER = logging.getLogger(__name__) + + +class UserCodeExecutionException(Exception): + """Base class for errors related to calling Web APIs.""" + + +class UserCodeQuotaException(UserCodeExecutionException): + """Extends ``UserCodeExecutionException`` to signal specifically that + the Web API client encountered a Quota or API overuse related error. + """ + + +class UserCodeTimeoutException(UserCodeExecutionException): + """Extends ``UserCodeExecutionException`` to signal a user code timeout.""" + + +def retry_on_exception(exception: Exception): + """retry on exceptions caused by unavailability of the remote server.""" + return isinstance( + exception, + (TooManyRequests, UserCodeTimeoutException, UserCodeQuotaException)) + + +class _MetricsCollector: + """A metrics collector that tracks RequestResponseIO related usage.""" + def __init__(self, namespace: str): + """ + Args: + namespace: Namespace for the metrics. + """ + self.requests = Metrics.counter(namespace, 'requests') + self.responses = Metrics.counter(namespace, 'responses') + self.failures = Metrics.counter(namespace, 'failures') + self.throttled_requests = Metrics.counter(namespace, 'throttled_requests') + self.throttled_secs = Metrics.counter( + namespace, 'cumulativeThrottlingSeconds') + self.timeout_requests = Metrics.counter(namespace, 'requests_timed_out') + self.call_counter = Metrics.counter(namespace, 'call_invocations') + self.setup_counter = Metrics.counter(namespace, 'setup_counter') + self.teardown_counter = Metrics.counter(namespace, 'teardown_counter') + self.backoff_counter = Metrics.counter(namespace, 'backoff_counter') + self.sleeper_counter = Metrics.counter(namespace, 'sleeper_counter') + self.should_backoff_counter = Metrics.counter( + namespace, 'should_backoff_counter') + + +class Caller(contextlib.AbstractContextManager, + abc.ABC, + Generic[RequestT, ResponseT]): + """Interface for user custom code intended for API calls. + For setup and teardown of clients when applicable, implement the + ``__enter__`` and ``__exit__`` methods respectively.""" + @abc.abstractmethod + def __call__(self, request: RequestT, *args, **kwargs) -> ResponseT: + """Calls a Web API with the ``RequestT`` and returns a + ``ResponseT``. ``RequestResponseIO`` expects implementations of the + ``__call__`` method to throw either a ``UserCodeExecutionException``, + ``UserCodeQuotaException``, or ``UserCodeTimeoutException``. + """ + pass + + def __enter__(self): + return self + + def __exit__(self, exc_type, exc_val, exc_tb): + return None + + +class ShouldBackOff(abc.ABC): + """ + ShouldBackOff provides mechanism to apply adaptive throttling. + """ + pass + + +class Repeater(abc.ABC): + """Repeater provides mechanism to repeat requests for a + configurable condition.""" + @abc.abstractmethod + def repeat( + self, + caller: Caller[RequestT, ResponseT], + request: RequestT, + timeout: float, + metrics_collector: Optional[_MetricsCollector]) -> ResponseT: + """repeat method is called from the RequestResponseIO when + a repeater is enabled. + + Args: + caller: :class:`apache_beam.io.requestresponse.Caller` object that calls + the API. + request: input request to repeat. + timeout: time to wait for the request to complete. + metrics_collector: (Optional) a + ``:class:`apache_beam.io.requestresponse._MetricsCollector``` object to + collect the metrics for RequestResponseIO. + """ + pass + + +def _execute_request( + caller: Caller[RequestT, ResponseT], + request: RequestT, + timeout: float, + metrics_collector: Optional[_MetricsCollector] = None) -> ResponseT: + with concurrent.futures.ThreadPoolExecutor() as executor: + future = executor.submit(caller, request) + try: + return future.result(timeout=timeout) + except TooManyRequests as e: + _LOGGER.warning( + 'request could not be completed. got code %i from the service.', + e.code) + raise e + except concurrent.futures.TimeoutError: + if metrics_collector: + metrics_collector.timeout_requests.inc(1) + raise UserCodeTimeoutException( + f'Timeout {timeout} exceeded ' + f'while completing request: {request}') + except RuntimeError: + if metrics_collector: + metrics_collector.failures.inc(1) + raise UserCodeExecutionException('could not complete request') + + +class ExponentialBackOffRepeater(Repeater): + """Exponential BackOff Repeater uses exponential backoff retry strategy for + exceptions due to the remote service such as TooManyRequests (HTTP 429), + UserCodeTimeoutException, UserCodeQuotaException. + + It utilizes the decorator + :func:`apache_beam.utils.retry.with_exponential_backoff`. + """ + def __init__(self): + pass + + @retry.with_exponential_backoff( + num_retries=2, retry_filter=retry_on_exception) + def repeat( + self, + caller: Caller[RequestT, ResponseT], + request: RequestT, + timeout: float, + metrics_collector: Optional[_MetricsCollector] = None) -> ResponseT: + """repeat method is called from the RequestResponseIO when + a repeater is enabled. + + Args: + caller: :class:`apache_beam.io.requestresponse.Caller` object that + calls the API. + request: input request to repeat. + timeout: time to wait for the request to complete. + metrics_collector: (Optional) a + ``:class:`apache_beam.io.requestresponse._MetricsCollector``` object to + collect the metrics for RequestResponseIO. + """ + return _execute_request(caller, request, timeout, metrics_collector) + + +class NoOpsRepeater(Repeater): + """ + NoOpsRepeater executes a request just once irrespective of any exception. + """ + def repeat( + self, + caller: Caller[RequestT, ResponseT], + request: RequestT, + timeout: float, + metrics_collector: Optional[_MetricsCollector]) -> ResponseT: + return _execute_request(caller, request, timeout, metrics_collector) + + +class CacheReader(abc.ABC): + """CacheReader provides mechanism to read from the cache.""" + pass + + +class CacheWriter(abc.ABC): + """CacheWriter provides mechanism to write to the cache.""" + pass + + +class PreCallThrottler(abc.ABC): + """PreCallThrottler provides a throttle mechanism before sending request.""" + pass + + +class DefaultThrottler(PreCallThrottler): + """Default throttler that uses + :class:`apache_beam.io.components.adaptive_throttler.AdaptiveThrottler` + + Args: + window_ms (int): length of history to consider, in ms, to set throttling. + bucket_ms (int): granularity of time buckets that we store data in, in ms. + overload_ratio (float): the target ratio between requests sent and + successful requests. This is "K" in the formula in + https://landing.google.com/sre/book/chapters/handling-overload.html. + delay_secs (int): minimum number of seconds to throttle a request. + """ + def __init__( + self, + window_ms: int = 1, + bucket_ms: int = 1, + overload_ratio: float = 2, + delay_secs: int = 5): + self.throttler = AdaptiveThrottler( + window_ms=window_ms, bucket_ms=bucket_ms, overload_ratio=overload_ratio) + self.delay_secs = delay_secs + + +class RequestResponseIO(beam.PTransform[beam.PCollection[RequestT], + beam.PCollection[ResponseT]]): + """A :class:`RequestResponseIO` transform to read and write to APIs. + + Processes an input :class:`~apache_beam.pvalue.PCollection` of requests + by making a call to the API as defined in :class:`Caller`'s `__call__` + and returns a :class:`~apache_beam.pvalue.PCollection` of responses. + """ + def __init__( + self, + caller: Caller[RequestT, ResponseT], + timeout: Optional[float] = DEFAULT_TIMEOUT_SECS, + should_backoff: Optional[ShouldBackOff] = None, + repeater: Optional[Repeater] = ExponentialBackOffRepeater(), Review Comment: sounds good! -- 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]
