feat: add support for S3 IntelligentTiering events

[oyiz-michael]

Issue number: closes #7443

Summary

Changes

This PR adds support for parsing S3 IntelligentTiering events, which have a different structure than standard S3 events.

Root cause: S3 IntelligentTiering events use "get_object" as the key name instead of "object" in the S3 message, and include an intelligentTieringEventData field with access tier information. The existing models only supported the "object" key, causing parsing failures.

Solution: Updated both parser models and data classes to handle both field names, making the implementation backward compatible with all existing S3 event types.

Files changed:

• aws_lambda_powertools/utilities/parser/models/s3.py: Added S3EventRecordIntelligentTieringEventData model, updated S3Message to support both object and get_object fields, and fixed validator
• aws_lambda_powertools/utilities/data_classes/s3_event.py: Added S3EventRecordIntelligentTieringEventData class, updated S3Message.get_object() and S3Event.object_key to handle both key names
• tests/events/s3EventIntelligentTiering.json: Added comprehensive test event
• tests/unit/parser/_pydantic/test_s3_intelligent_tiering.py: Added parser model tests (2 tests)
• tests/unit/data_classes/required_dependencies/test_s3_intelligent_tiering_event.py: Added data classes tests (3 tests)

User experience

Before:

from aws_lambda_powertools.utilities.data_classes import S3Event
from aws_lambda_powertools.utilities.parser import parse

# IntelligentTiering events would fail to parse
@event_source(data_class=S3Event)
def handler(event: S3Event, context):
    # Would raise KeyError: 'object'
    object_key = event.object_key
    
# Parser would also fail
def handler(event, context):
    # Would fail validation
    parsed = parse(event, model=S3Model)

After

from aws_lambda_powertools.utilities.data_classes import S3Event
from aws_lambda_powertools.utilities.parser import parse

# IntelligentTiering events now parse correctly
@event_source(data_class=S3Event)
def handler(event: S3Event, context):
    # Works with both standard S3 events and IntelligentTiering events
    object_key = event.object_key  
    
    # Access IntelligentTiering-specific data
    if event.record.intelligent_tiering_event_data:
        tier = event.record.intelligent_tiering_event_data.destination_access_tier
        # tier will be "ARCHIVE_ACCESS" or "DEEP_ARCHIVE_ACCESS"
    
# Parser also works
def handler(event, context):
    parsed = parse(event, model=S3Model)  
    record = parsed.Records[0]
    
    if record.intelligentTieringEventData:
        tier = record.intelligentTieringEventData.destinationAccessTier

All existing S3 event types continue to work as before - the changes are fully backward compatible.

Testing:

Added 5 new tests covering both parser models and data classes
All 17 S3-related tests pass (5 new + 12 existing)
No regressions in existing S3 event parsing

---

By submitting this pull request, I confirm that you can use, modify, copy, and redistribute this contribution, under the terms of your choice.

Disclaimer: We value your time and bandwidth. As such, any pull requests created on non-triaged issues might not be successful.

[sonarqubecloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarQube Cloud