ignore orphaned counters

The purpose of this module is to expose metrics for prometheus. As
such, we are building time series from the counters. This means we
should not expose metrics that do not exist anymore: configured out
from syslog-ng and reloaded. This patch filters out orphan counters.

Signed-off-by: Antal Nemes <antal.nemes@axoflow.com>

pkg/syslog-ng-ctl/stats.go

@@ -76,14 +76,17 @@ func parseStats(rsp string) (stats []Stat, errs error) {
 			errs = errors.Join(errs, err)
 			continue
 		}
-		stats = append(stats, Stat{
-			SourceName:     fields[0],
-			SourceID:       fields[1],
-			SourceInstance: fields[2],
-			SourceState:    SourceState(fields[3][0]),
-			Type:           fields[4],
-			Number:         num,
-		})
+
+		if fields[3] != string(SourceStateOrphaned) {
+			stats = append(stats, Stat{
+				SourceName:     fields[0],
+				SourceID:       fields[1],
+				SourceInstance: fields[2],
+				SourceState:    SourceState(fields[3][0]),
+				Type:           fields[4],
+				Number:         num,
+			})
+		}
 	}
 	return
 }

pkg/syslog-ng-ctl/stats_test.go

@@ -56,6 +56,18 @@ src.internal;s_src#1;;a;processed;59
 src.internal;s_src#1;;a;stamp;1673105444
 destination;d_newserr;;a;processed;0
 global;scratch_buffers_bytes;;a;queued;0
+dst.network;#anon-destination0#0;tcp,localhost:1234;o;eps_last_1h;0
+dst.network;#anon-destination0#0;tcp,localhost:1234;o;eps_last_24h;0
+dst.network;#anon-destination0#0;tcp,localhost:1234;o;dropped;0
+dst.network;#anon-destination0#0;tcp,localhost:1234;o;processed;0
+dst.network;#anon-destination0#0;tcp,localhost:1234;o;queued;0
+dst.network;#anon-destination0#0;tcp,localhost:1234;o;memory_usage;0
+dst.network;#anon-destination0#0;tcp,localhost:1234;o;written;0
+dst.network;#anon-destination0#0;tcp,localhost:1234;o;truncated_bytes;0
+dst.network;#anon-destination0#0;tcp,localhost:1234;o;eps_since_start;0
+dst.network;#anon-destination0#0;tcp,localhost:1234;o;msg_size_max;0
+dst.network;#anon-destination0#0;tcp,localhost:1234;o;truncated_count;0
+dst.network;#anon-destination0#0;tcp,localhost:1234;o;msg_size_avg;0
 .
 `
 	expected := []Stat{