Source code for sosw.worker

"""
..  hidden-code-block:: text
    :label: View Licence Agreement <br>

    sosw - Serverless Orchestrator of Serverless Workers

    The MIT License (MIT)
    Copyright (C) 2024  sosw core contributors <info@sosw.app>

    Permission is hereby granted, free of charge, to any person obtaining a copy
    of this software and associated documentation files (the "Software"), to deal
    in the Software without restriction, including without limitation the rights
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    The above copyright notice and this permission notice shall be included in all
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    FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
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"""

__all__ = ['Worker']
__author__ = "Nikolay Grishchenko"
__version__ = "1.0"

try:
    from aws_lambda_powertools import Logger

    logger = Logger()

except ImportError:
    import logging

    logger = logging.getLogger()
    logger.setLevel(logging.INFO)

import json

from sosw.app import Processor
from sosw.managers.meta_handler import MetaHandler
from typing import Dict


[docs] class Worker(Processor): """ We recommend that you inherit your core Processor from this class in Lambdas that are orchestrated by `sosw`. The ``__call__`` method is supposed to accept the ``event`` of the Lambda invocation. This is a dictionary with the payload received in the lambda_handler during invocation. Worker has all the common methods of :ref:`Processor` and tries to mark task as completed if received ``task_id`` in the ``event``. Worker create a payload with ``stats`` and ``result`` if exist and invoke worker assistant lambda. Worker class can optionally record ``'completed'`` and ``'failed'`` events to the DynamoDB tasks meta data table. In order to enable this feature, you have to provide ``'meta_handler_config'`` in your custom_config. You also need to grant write permissions for this table to your Lambda. You can find more information about the configuration in the :ref:`MetaHandler<meta_handler>` chapter. """ DEFAULT_CONFIG = { 'init_clients': ['lambda'], 'sosw_worker_assistant_lambda': 'sosw_worker_assistant' } lambda_client = None meta_handler: MetaHandler = None def __init__(self, *args, **kwargs): super().__init__(*args, **kwargs) if 'meta_handler_config' in self.config: self.meta_handler = MetaHandler(custom_config=self.config['meta_handler_config']) def __call__(self, event: Dict, reset_result: bool = True): """ You can either call super() at the end of your child function or completely overwrite this function. :param reset_result: Whether to reset the result after the processor call. Defaults to True. """ # Mark the task as completed in DynamoDB if the event had task_id. try: if event.get('task_id'): self.mark_task_as_completed(event['task_id']) except Exception: logger.exception(f"Failed to call WorkerAssistant for event {event}") pass super().__call__(event, reset_result)
[docs] def mark_task_as_completed(self, task_id: str): """ Call worker assistant lambda and tell it to close task """ if not self.lambda_client: self.register_clients(['lambda']) worker_assistant_lambda_name = self.config.get('sosw_worker_assistant_lambda', 'sosw_worker_assistant') payload = { 'action': 'mark_task_as_completed', 'task_id': task_id, } if self.stats: payload.update({'stats': self.stats}) if self.result: payload.update({'result': self.result}) payload = json.dumps(payload) lambda_response = self.lambda_client.invoke( FunctionName=worker_assistant_lambda_name, InvocationType='Event', Payload=payload ) if self.meta_handler: self.meta_handler.post(task_id=task_id, action='completed') logger.debug(f"mark_task_as_completed response: {lambda_response}")
[docs] def mark_task_as_failed(self, task_id: str): """ Call worker assistant lambda and tell it to update task info """ if not self.lambda_client: self.register_clients(['lambda']) worker_assistant_lambda_name = self.config.get('sosw_worker_assistant_lambda', 'sosw_worker_assistant') payload = { 'action': 'mark_task_as_failed', 'task_id': task_id, } if self.stats: payload.update({'stats': self.stats}) if self.result: payload.update({'result': self.result}) payload = json.dumps(payload) lambda_response = self.lambda_client.invoke( FunctionName=worker_assistant_lambda_name, InvocationType='Event', Payload=payload ) if self.meta_handler: self.meta_handler.post(task_id=task_id, action='failed') logger.debug(f"mark_task_as_failed response: {lambda_response}")