eventcachemetrics: Initialize metrics with labels

Initialize tetragon_event_cache_retries_total with all possible entry types.

Initialize tetragon_event_cache_<entry_type>_errors_total with all possible
event types.

Initialize tetragon_event_cache_errors_total with all (one) possible errors and
all possible event types.

Signed-off-by: Anna Kapuscinska <anna@isovalent.com>

pkg/metrics/eventcachemetrics/eventcachemetrics.go

@@ -84,12 +84,18 @@ func InitMetrics(registry *prometheus.Registry) {
 	registerMetrics(registry)
 
 	// Initialize metrics with labels
+	for e := range cacheEntryTypeLabelValues {
+		EventCacheRetries(e)
+	}
+	for e := range tetragon.EventType_name {
+		if tetragon.EventType(e) != tetragon.EventType_UNDEF && tetragon.EventType(e) != tetragon.EventType_TEST {
+			ProcessInfoError(tetragon.EventType(e)).Add(0)
+			PodInfoError(tetragon.EventType(e)).Add(0)
+			ParentInfoError(tetragon.EventType(e)).Add(0)
+		}
+	}
 	// TODO:
-	// event_cache_process_info_errors_total: list all possible event types
-	// event_cache_pod_info_errors_total: list all possible event types
 	// event_cache_errors_total: list all possible errors
-	// event_cache_retries_total: list all possible entry types
-	// event_cache_parent_info_errors_total: list all possible event types
 
 	// NOTES:
 	// * Consider merging some metrics together (e.g. keep one errors metric with event_type and error labels)