External Absences are implemented as a controlled synchronization flow between an external absence source and the employee absence records used by AristoTelos.

The import job can run automatically at configured times or be started manually. Before processing records, it validates its connection, parameters, and absence-type mapping. If this setup is invalid, the run stops without applying partial updates.

During processing, AristoTelos:

1. Retrieves and retains the input data needed for troubleshooting.
2. Matches an external absence to an employee using the employee's personal identifier.
3. Creates a new external absence or updates an existing one.
4. Maps the external illness type and work-accident indicator to an AristoTelos Time Off Type.
5. Creates or updates the linked employee absence when the change is permitted.
6. Respects manual overrides through the separate start, end, and type synchronization controls.
7. Records unsuccessful updates and retries unresolved employee assignments up to the configured limit.
8. Prevents changes that would affect a closed attendance interval and records the reason for the rejected update.

All changes to external absence records are written to the audit log, while changes to linked roster records are captured in shift history. The job produces user-readable processing logs and sends a completion notification for both successful and failed runs.

Business impact

This implementation reduces repeated manual entry of externally managed absences and keeps planning data aligned with the external source. Separate synchronization controls preserve HR and administrator decisions, while statuses, retries, logs, and audit history make exceptions visible and traceable.

The source-specific retrieval is separated from the synchronization behavior, allowing the same business flow to be adapted to another external source without redesigning how absences are represented and applied in AristoTelos.