Module aws_lambda_powertools.utilities.batch.sqs
Batch SQS utilities
Expand source code
# -*- coding: utf-8 -*-
"""
Batch SQS utilities
"""
import logging
import math
import sys
from concurrent.futures import ThreadPoolExecutor, as_completed
from typing import Any, Callable, Dict, List, Optional, Tuple, cast
import boto3
from botocore.config import Config
from aws_lambda_powertools.utilities.data_classes.sqs_event import SQSRecord
from ...middleware_factory import lambda_handler_decorator
from .base import BasePartialProcessor
from .exceptions import SQSBatchProcessingError
logger = logging.getLogger(__name__)
class PartialSQSProcessor(BasePartialProcessor):
"""
Amazon SQS batch processor to delete successes from the Queue.
The whole batch will be processed, even if failures occur. After all records are processed,
SQSBatchProcessingError will be raised if there were any failures, causing messages to
be returned to the SQS queue. This behaviour can be disabled by passing suppress_exception.
Parameters
----------
config: Config
botocore config object
suppress_exception: bool, optional
Supress exception raised if any messages fail processing, by default False
boto3_session : boto3.session.Session, optional
Boto3 session to use for AWS API communication
Example
-------
**Process batch triggered by SQS**
>>> from aws_lambda_powertools.utilities.batch import PartialSQSProcessor
>>>
>>> def record_handler(record):
>>> return record["body"]
>>>
>>> def handler(event, context):
>>> records = event["Records"]
>>> processor = PartialSQSProcessor()
>>>
>>> with processor(records=records, handler=record_handler):
>>> result = processor.process()
>>>
>>> # Case a partial failure occurred, all successful executions
>>> # have been deleted from the queue after context's exit.
>>>
>>> return result
"""
def __init__(
self,
config: Optional[Config] = None,
suppress_exception: bool = False,
boto3_session: Optional[boto3.session.Session] = None,
):
"""
Initializes sqs client.
"""
config = config or Config()
session = boto3_session or boto3.session.Session()
self.client = session.client("sqs", config=config)
self.suppress_exception = suppress_exception
self.max_message_batch = 10
super().__init__()
def _get_queue_url(self) -> Optional[str]:
"""
Format QueueUrl from first records entry
"""
if not getattr(self, "records", None):
return None
*_, account_id, queue_name = self.records[0]["eventSourceARN"].split(":")
return f"{self.client._endpoint.host}/{account_id}/{queue_name}"
def _get_entries_to_clean(self) -> List[Dict[str, str]]:
"""
Format messages to use in batch deletion
"""
entries = []
# success_messages has generic type of union of SQS, Dynamodb and Kinesis Streams records or Pydantic models.
# Here we get SQS Record only
messages = cast(List[SQSRecord], self.success_messages)
for msg in messages:
entries.append({"Id": msg["messageId"], "ReceiptHandle": msg["receiptHandle"]})
return entries
def _process_record(self, record) -> Tuple:
"""
Process a record with instance's handler
Parameters
----------
record: Any
An object to be processed.
"""
try:
result = self.handler(record=record)
return self.success_handler(record=record, result=result)
except Exception:
return self.failure_handler(record=record, exception=sys.exc_info())
def _prepare(self):
"""
Remove results from previous execution.
"""
self.success_messages.clear()
self.fail_messages.clear()
def _clean(self) -> Optional[List]:
"""
Delete messages from Queue in case of partial failure.
"""
# If all messages were successful, fall back to the default SQS -
# Lambda behavior which deletes messages if Lambda responds successfully
if not self.fail_messages:
logger.debug(f"All {len(self.success_messages)} records successfully processed")
return None
queue_url = self._get_queue_url()
if queue_url is None:
logger.debug("No queue url found")
return None
entries_to_remove = self._get_entries_to_clean()
# Batch delete up to 10 messages at a time (SQS limit)
max_workers = math.ceil(len(entries_to_remove) / self.max_message_batch)
if entries_to_remove:
with ThreadPoolExecutor(max_workers=max_workers) as executor:
futures, results = [], []
while entries_to_remove:
futures.append(
executor.submit(
self._delete_messages, queue_url, entries_to_remove[: self.max_message_batch], self.client
)
)
entries_to_remove = entries_to_remove[self.max_message_batch :]
for future in as_completed(futures):
try:
logger.debug("Deleted batch of processed messages from SQS")
results.append(future.result())
except Exception:
logger.exception("Couldn't remove batch of processed messages from SQS")
raise
if self.suppress_exception:
logger.debug(f"{len(self.fail_messages)} records failed processing, but exceptions are suppressed")
else:
logger.debug(f"{len(self.fail_messages)} records failed processing, raising exception")
raise SQSBatchProcessingError(
msg=f"Not all records processed successfully. {len(self.exceptions)} individual errors logged "
f"separately below.",
child_exceptions=self.exceptions,
)
return results
def _delete_messages(self, queue_url: str, entries_to_remove: List, sqs_client: Any):
delete_message_response = sqs_client.delete_message_batch(
QueueUrl=queue_url,
Entries=entries_to_remove,
)
return delete_message_response
@lambda_handler_decorator
def sqs_batch_processor(
handler: Callable,
event: Dict,
context: Dict,
record_handler: Callable,
config: Optional[Config] = None,
suppress_exception: bool = False,
boto3_session: Optional[boto3.session.Session] = None,
):
"""
Middleware to handle SQS batch event processing
Parameters
----------
handler: Callable
Lambda's handler
event: Dict
Lambda's Event
context: Dict
Lambda's Context
record_handler: Callable
Callable to process each record from the batch
config: Config
botocore config object
suppress_exception: bool, optional
Supress exception raised if any messages fail processing, by default False
boto3_session : boto3.session.Session, optional
Boto3 session to use for AWS API communication
Examples
--------
**Processes Lambda's event with PartialSQSProcessor**
>>> from aws_lambda_powertools.utilities.batch import sqs_batch_processor
>>>
>>> def record_handler(record):
>>> return record["body"]
>>>
>>> @sqs_batch_processor(record_handler=record_handler)
>>> def handler(event, context):
>>> return {"StatusCode": 200}
Limitations
-----------
* Async batch processors
"""
config = config or Config()
session = boto3_session or boto3.session.Session()
processor = PartialSQSProcessor(config=config, suppress_exception=suppress_exception, boto3_session=session)
records = event["Records"]
with processor(records, record_handler):
processor.process()
return handler(event, context)
Functions
def sqs_batch_processor(handler: Callable, event: Dict[~KT, ~VT], context: Dict[~KT, ~VT], record_handler: Callable, config: Optional[botocore.config.Config] = None, suppress_exception: bool = False, boto3_session: Optional[boto3.session.Session] = None)
-
Middleware to handle SQS batch event processing
Parameters
handler
:Callable
- Lambda's handler
event
:Dict
- Lambda's Event
context
:Dict
- Lambda's Context
record_handler
:Callable
- Callable to process each record from the batch
config
:Config
- botocore config object
suppress_exception
:bool
, optional- Supress exception raised if any messages fail processing, by default False
boto3_session
:boto3.session.Session
, optional- Boto3 session to use for AWS API communication
Examples
Processes Lambda's event with PartialSQSProcessor
>>> from aws_lambda_powertools.utilities.batch import sqs_batch_processor >>> >>> def record_handler(record): >>> return record["body"] >>> >>> @sqs_batch_processor(record_handler=record_handler) >>> def handler(event, context): >>> return {"StatusCode": 200}
Limitations
- Async batch processors
Expand source code
@lambda_handler_decorator def sqs_batch_processor( handler: Callable, event: Dict, context: Dict, record_handler: Callable, config: Optional[Config] = None, suppress_exception: bool = False, boto3_session: Optional[boto3.session.Session] = None, ): """ Middleware to handle SQS batch event processing Parameters ---------- handler: Callable Lambda's handler event: Dict Lambda's Event context: Dict Lambda's Context record_handler: Callable Callable to process each record from the batch config: Config botocore config object suppress_exception: bool, optional Supress exception raised if any messages fail processing, by default False boto3_session : boto3.session.Session, optional Boto3 session to use for AWS API communication Examples -------- **Processes Lambda's event with PartialSQSProcessor** >>> from aws_lambda_powertools.utilities.batch import sqs_batch_processor >>> >>> def record_handler(record): >>> return record["body"] >>> >>> @sqs_batch_processor(record_handler=record_handler) >>> def handler(event, context): >>> return {"StatusCode": 200} Limitations ----------- * Async batch processors """ config = config or Config() session = boto3_session or boto3.session.Session() processor = PartialSQSProcessor(config=config, suppress_exception=suppress_exception, boto3_session=session) records = event["Records"] with processor(records, record_handler): processor.process() return handler(event, context)
Classes
class PartialSQSProcessor (config: Optional[botocore.config.Config] = None, suppress_exception: bool = False, boto3_session: Optional[boto3.session.Session] = None)
-
Amazon SQS batch processor to delete successes from the Queue.
The whole batch will be processed, even if failures occur. After all records are processed, SQSBatchProcessingError will be raised if there were any failures, causing messages to be returned to the SQS queue. This behaviour can be disabled by passing suppress_exception.
Parameters
config
:Config
- botocore config object
suppress_exception
:bool
, optional- Supress exception raised if any messages fail processing, by default False
boto3_session
:boto3.session.Session
, optional- Boto3 session to use for AWS API communication
Example
Process batch triggered by SQS
>>> from aws_lambda_powertools.utilities.batch import PartialSQSProcessor >>> >>> def record_handler(record): >>> return record["body"] >>> >>> def handler(event, context): >>> records = event["Records"] >>> processor = PartialSQSProcessor() >>> >>> with processor(records=records, handler=record_handler): >>> result = processor.process() >>> >>> # Case a partial failure occurred, all successful executions >>> # have been deleted from the queue after context's exit. >>> >>> return result
Initializes sqs client.
Expand source code
class PartialSQSProcessor(BasePartialProcessor): """ Amazon SQS batch processor to delete successes from the Queue. The whole batch will be processed, even if failures occur. After all records are processed, SQSBatchProcessingError will be raised if there were any failures, causing messages to be returned to the SQS queue. This behaviour can be disabled by passing suppress_exception. Parameters ---------- config: Config botocore config object suppress_exception: bool, optional Supress exception raised if any messages fail processing, by default False boto3_session : boto3.session.Session, optional Boto3 session to use for AWS API communication Example ------- **Process batch triggered by SQS** >>> from aws_lambda_powertools.utilities.batch import PartialSQSProcessor >>> >>> def record_handler(record): >>> return record["body"] >>> >>> def handler(event, context): >>> records = event["Records"] >>> processor = PartialSQSProcessor() >>> >>> with processor(records=records, handler=record_handler): >>> result = processor.process() >>> >>> # Case a partial failure occurred, all successful executions >>> # have been deleted from the queue after context's exit. >>> >>> return result """ def __init__( self, config: Optional[Config] = None, suppress_exception: bool = False, boto3_session: Optional[boto3.session.Session] = None, ): """ Initializes sqs client. """ config = config or Config() session = boto3_session or boto3.session.Session() self.client = session.client("sqs", config=config) self.suppress_exception = suppress_exception self.max_message_batch = 10 super().__init__() def _get_queue_url(self) -> Optional[str]: """ Format QueueUrl from first records entry """ if not getattr(self, "records", None): return None *_, account_id, queue_name = self.records[0]["eventSourceARN"].split(":") return f"{self.client._endpoint.host}/{account_id}/{queue_name}" def _get_entries_to_clean(self) -> List[Dict[str, str]]: """ Format messages to use in batch deletion """ entries = [] # success_messages has generic type of union of SQS, Dynamodb and Kinesis Streams records or Pydantic models. # Here we get SQS Record only messages = cast(List[SQSRecord], self.success_messages) for msg in messages: entries.append({"Id": msg["messageId"], "ReceiptHandle": msg["receiptHandle"]}) return entries def _process_record(self, record) -> Tuple: """ Process a record with instance's handler Parameters ---------- record: Any An object to be processed. """ try: result = self.handler(record=record) return self.success_handler(record=record, result=result) except Exception: return self.failure_handler(record=record, exception=sys.exc_info()) def _prepare(self): """ Remove results from previous execution. """ self.success_messages.clear() self.fail_messages.clear() def _clean(self) -> Optional[List]: """ Delete messages from Queue in case of partial failure. """ # If all messages were successful, fall back to the default SQS - # Lambda behavior which deletes messages if Lambda responds successfully if not self.fail_messages: logger.debug(f"All {len(self.success_messages)} records successfully processed") return None queue_url = self._get_queue_url() if queue_url is None: logger.debug("No queue url found") return None entries_to_remove = self._get_entries_to_clean() # Batch delete up to 10 messages at a time (SQS limit) max_workers = math.ceil(len(entries_to_remove) / self.max_message_batch) if entries_to_remove: with ThreadPoolExecutor(max_workers=max_workers) as executor: futures, results = [], [] while entries_to_remove: futures.append( executor.submit( self._delete_messages, queue_url, entries_to_remove[: self.max_message_batch], self.client ) ) entries_to_remove = entries_to_remove[self.max_message_batch :] for future in as_completed(futures): try: logger.debug("Deleted batch of processed messages from SQS") results.append(future.result()) except Exception: logger.exception("Couldn't remove batch of processed messages from SQS") raise if self.suppress_exception: logger.debug(f"{len(self.fail_messages)} records failed processing, but exceptions are suppressed") else: logger.debug(f"{len(self.fail_messages)} records failed processing, raising exception") raise SQSBatchProcessingError( msg=f"Not all records processed successfully. {len(self.exceptions)} individual errors logged " f"separately below.", child_exceptions=self.exceptions, ) return results def _delete_messages(self, queue_url: str, entries_to_remove: List, sqs_client: Any): delete_message_response = sqs_client.delete_message_batch( QueueUrl=queue_url, Entries=entries_to_remove, ) return delete_message_response
Ancestors
- BasePartialProcessor
- abc.ABC
Inherited members