Change #239812

Comments

impstats: add support for Prometheus metrics output format
This commit extends the impstats input module to support a new
"prometheus" format for exporting statistics. The output is
generated via statsobj.c, which already provides Prometheus-
compatible formatting.

To enable this, a new "format" config option value ("prometheus")
was added and recognized by impstats.c. When selected, impstats
invokes the appropriate statsobj function to generate output in
Prometheus exposition format.

The default behavior remains unchanged. Existing formats such as
"json" and "legacy" are not modified.

A new test has been added under tests/ to validate correct
Prometheus output generation. The test verifies that the format
header and at least one representative metric line conform to the
Prometheus text format specification.

This enhancement enables rsyslog to integrate more easily with
Prometheus-based monitoring stacks and paves the way for native
metrics scraping without external translation layers.

Changed files

• plugins/impstats/impstats.c
• tests/Makefile.am
• tests/stats-prometheus.sh