|
| 1 | +import datetime |
| 2 | +import random |
| 3 | +from logging import getLogger |
| 4 | +from typing import Any, Optional |
| 5 | + |
| 6 | +from taskiq import ScheduleSource |
| 7 | +from taskiq.abc.middleware import TaskiqMiddleware |
| 8 | +from taskiq.exceptions import NoResultError |
| 9 | +from taskiq.kicker import AsyncKicker |
| 10 | +from taskiq.message import TaskiqMessage |
| 11 | +from taskiq.result import TaskiqResult |
| 12 | + |
| 13 | +__all__ = ("SmartRetryMiddleware",) |
| 14 | + |
| 15 | +_logger = getLogger("taskiq.smart_retry_middleware") |
| 16 | + |
| 17 | + |
| 18 | +class SmartRetryMiddleware(TaskiqMiddleware): |
| 19 | + """Middleware to retry tasks delays. |
| 20 | +
|
| 21 | + This middleware retries failed tasks with support for: |
| 22 | + - max retries |
| 23 | + - delay |
| 24 | + - jitter |
| 25 | + - exponential backoff |
| 26 | + """ |
| 27 | + |
| 28 | + def __init__( |
| 29 | + self, |
| 30 | + default_retry_count: int = 3, |
| 31 | + default_retry_label: bool = False, |
| 32 | + no_result_on_retry: bool = True, |
| 33 | + default_delay: float = 5, |
| 34 | + use_jitter: bool = False, |
| 35 | + use_delay_exponent: bool = False, |
| 36 | + max_delay_exponent: float = 60, |
| 37 | + schedule_source: Optional[ScheduleSource] = None, |
| 38 | + ) -> None: |
| 39 | + """ |
| 40 | + Initialize retry middleware. |
| 41 | +
|
| 42 | + :param default_retry_count: Default max retries if not specified. |
| 43 | + :param default_retry_label: Whether to retry tasks by default. |
| 44 | + :param no_result_on_retry: Replace result with NoResultError on retry. |
| 45 | + :param default_delay: Delay in seconds before retrying. |
| 46 | + :param use_jitter: Add random jitter to retry delay. |
| 47 | + :param use_delay_exponent: Apply exponential backoff to delay. |
| 48 | + :param max_delay_exponent: Maximum allowed delay when using backoff. |
| 49 | + :param schedule_source: Schedule source to use for scheduling. |
| 50 | + If None, the default broker will be used. |
| 51 | + """ |
| 52 | + super().__init__() |
| 53 | + self.default_retry_count = default_retry_count |
| 54 | + self.default_retry_label = default_retry_label |
| 55 | + self.no_result_on_retry = no_result_on_retry |
| 56 | + self.default_delay = default_delay |
| 57 | + self.use_jitter = use_jitter |
| 58 | + self.use_delay_exponent = use_delay_exponent |
| 59 | + self.max_delay_exponent = max_delay_exponent |
| 60 | + self.schedule_source = schedule_source |
| 61 | + |
| 62 | + if not isinstance(schedule_source, (ScheduleSource, type(None))): |
| 63 | + raise TypeError( |
| 64 | + "schedule_source must be an instance of ScheduleSource or None", |
| 65 | + ) |
| 66 | + |
| 67 | + def is_retry_on_error(self, message: TaskiqMessage) -> bool: |
| 68 | + """ |
| 69 | + Check if retry is enabled for this task. |
| 70 | +
|
| 71 | + Looks for `retry_on_error` label, falls back to default. |
| 72 | +
|
| 73 | + :param message: Original task message. |
| 74 | + :return: True if should retry on error. |
| 75 | + """ |
| 76 | + retry_on_error = message.labels.get("retry_on_error") |
| 77 | + if isinstance(retry_on_error, str): |
| 78 | + retry_on_error = retry_on_error.lower() == "true" |
| 79 | + if retry_on_error is None: |
| 80 | + retry_on_error = self.default_retry_label |
| 81 | + return retry_on_error |
| 82 | + |
| 83 | + def make_delay(self, message: TaskiqMessage, retries: int) -> float: |
| 84 | + """ |
| 85 | + Calculate retry delay. |
| 86 | +
|
| 87 | + Includes jitter and exponential backoff if enabled. |
| 88 | +
|
| 89 | + :param message: Task message. |
| 90 | + :param retries: Current retry count. |
| 91 | + :return: Delay in seconds. |
| 92 | + """ |
| 93 | + delay = float(message.labels.get("delay", self.default_delay)) |
| 94 | + if self.use_delay_exponent: |
| 95 | + delay = min(delay * retries, self.max_delay_exponent) |
| 96 | + |
| 97 | + if self.use_jitter: |
| 98 | + delay += random.random() # noqa: S311 |
| 99 | + |
| 100 | + return delay |
| 101 | + |
| 102 | + async def on_send( |
| 103 | + self, |
| 104 | + kicker: AsyncKicker[Any, Any], |
| 105 | + message: TaskiqMessage, |
| 106 | + delay: float, |
| 107 | + ) -> None: |
| 108 | + """Execute the task with a delay.""" |
| 109 | + if self.schedule_source is None: |
| 110 | + await kicker.with_labels(delay=delay).kiq(*message.args, **message.kwargs) |
| 111 | + else: |
| 112 | + target_time = datetime.datetime.now(datetime.UTC) + datetime.timedelta( |
| 113 | + seconds=delay, |
| 114 | + ) |
| 115 | + await kicker.schedule_by_time( |
| 116 | + self.schedule_source, |
| 117 | + target_time, |
| 118 | + *message.args, |
| 119 | + **message.kwargs, |
| 120 | + ) |
| 121 | + |
| 122 | + async def on_error( |
| 123 | + self, |
| 124 | + message: TaskiqMessage, |
| 125 | + result: TaskiqResult[Any], |
| 126 | + exception: BaseException, |
| 127 | + ) -> None: |
| 128 | + """ |
| 129 | + Retry on error. |
| 130 | +
|
| 131 | + If an error is raised during task execution, |
| 132 | + this middleware schedules the task to be retried |
| 133 | + after a calculated delay. |
| 134 | +
|
| 135 | + :param message: Message that caused the error. |
| 136 | + :param result: Execution result. |
| 137 | + :param exception: Caught exception. |
| 138 | + """ |
| 139 | + if isinstance(exception, NoResultError): |
| 140 | + return |
| 141 | + |
| 142 | + retry_on_error = self.is_retry_on_error(message) |
| 143 | + |
| 144 | + if not retry_on_error: |
| 145 | + return |
| 146 | + |
| 147 | + retries = int(message.labels.get("_retries", 0)) + 1 |
| 148 | + max_retries = int(message.labels.get("max_retries", self.default_retry_count)) |
| 149 | + |
| 150 | + if retries < max_retries: |
| 151 | + delay = self.make_delay(message, retries) |
| 152 | + |
| 153 | + _logger.info( |
| 154 | + "Task %s failed. Retrying %d/%d in %.2f seconds.", |
| 155 | + message.task_name, |
| 156 | + retries, |
| 157 | + max_retries, |
| 158 | + delay, |
| 159 | + ) |
| 160 | + |
| 161 | + kicker: AsyncKicker[Any, Any] = ( |
| 162 | + AsyncKicker( |
| 163 | + task_name=message.task_name, |
| 164 | + broker=self.broker, |
| 165 | + labels=message.labels, |
| 166 | + ) |
| 167 | + .with_task_id(message.task_id) |
| 168 | + .with_labels(_retries=retries) |
| 169 | + ) |
| 170 | + |
| 171 | + await self.on_send(kicker, message, delay) |
| 172 | + |
| 173 | + if self.no_result_on_retry: |
| 174 | + result.error = NoResultError() |
| 175 | + |
| 176 | + else: |
| 177 | + _logger.warning( |
| 178 | + "Task '%s' invocation failed. Maximum retries count is reached.", |
| 179 | + message.task_name, |
| 180 | + ) |
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