[soujasK]

Issue number: closes #8660

Summary

Changes

When converting a record to the customer's model raised something other than the model's ValidationError (Pydantic v2 only wraps ValueError/AssertionError from validators, so e.g. a KeyError escapes as-is), BatchProcessor._process_record and AsyncBatchProcessor._async_process_record called failure_handler(record=data) with data still None. None ended up in fail_messages, and _clean() then crashed in _collect_*_failures with AttributeError: 'NoneType' object has no attribute 'message_id'.

data is None in the except block means the conversion itself failed, so those records now go through the existing _register_model_validation_error_record path from #2091, which converts the raw record to the event source data class and registers it with the original exception.

Tests: a model whose field_validator raises KeyError for one record of three, for the sync and async processors. Both failed with the AttributeError before the change and pass after it; batch.exceptions keeps the original KeyError. tests/functional/batch passes on Linux (Python 3.12), along with ruff, mypy, ty, bandit and xenon.

User experience

Before: one malformed record fails the whole invocation with an AttributeError that hides the real error, and every record in the batch is retried, including the ones that already succeeded.

After: the malformed record is reported in batchItemFailures (as an event source data class, as documented for early model failures) and the rest of the batch is processed normally.

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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

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