Fix: Rename metrics to use unix timestamps

Changed the metrics for last reload and application start to report Unix timestamps instead of seconds since the events. This provides precise timestamps for better tracking and analysis.

Signed-off-by: Christian Roessner <c@roessner.co>

server/stats/statistics.go

@@ -42,27 +42,27 @@ func init() {
 	// Create the metric for the time since last reload
 	promauto.NewGaugeFunc(
 		prometheus.GaugeOpts{
-			Name: "nauthilus_seconds_since_last_reload",
-			Help: "Number of seconds since the application was last reloaded",
+			Name: "nauthilus_last_reload_timestamp",
+			Help: "Unix timestamp of the last reload",
 		},
 		func() float64 {
 			ReloadMutex.RLock()
 
 			defer ReloadMutex.RUnlock()
 
-			return time.Since(LastReloadTime).Seconds()
+			return float64(LastReloadTime.Unix())
 		},
 	)
 
 	startTime := time.Now()
 
 	promauto.NewGaugeFunc(
 		prometheus.GaugeOpts{
-			Name: "nauthilus_seconds_since_start",
-			Help: "Number of seconds since the application has started",
+			Name: "nauthilus_start_timestamp",
+			Help: "Unix timestamp of the application start",
 		},
 		func() float64 {
-			return time.Since(startTime).Seconds()
+			return float64(startTime.Unix())
 		},
 	)
 }