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Werk #19884: Fix crash in REST API host endpoints when inventory data is JSON-encoded

Component REST API
Title Fix crash in REST API host endpoints when inventory data is JSON-encoded
Date Jul 8, 2026
Level Trivial Change
Class Bug Fix
Compatibility Compatible - no manual interaction needed
Checkmk versions & editions
2.5.0p9 Checkmk Community, Checkmk Pro, Checkmk Ultimate, Checkmk Cloud, Checkmk Ultimate MT

Since Werk #18032, inventory trees are saved as JSON. However, some hosts may still have inventory data stored in the older Python-repr format.

The REST API host endpoints (cmk/list and cmk/show) always parsed the mk_inventory column with ast.literal_eval, which cannot handle JSON's true/false/null literals. As a result, requesting this column crashed for hosts whose inventory data was already stored as JSON.

The endpoints now understand both formats: they first try to parse the column as JSON, and only fall back to ast.literal_eval for hosts that still carry inventory data in the legacy Python-repr format.

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