From 23e78f2afe50f31e958ce29652cb023901c203f0 Mon Sep 17 00:00:00 2001
From: Simon Rieger <simon@rieger.app>
Date: Mon, 21 Jul 2025 09:42:05 +0200
Subject: [PATCH] fix local diggest tag check

---
 go/main.go | 41 ++++++++++++++++++++++++-----------------
 1 file changed, 24 insertions(+), 17 deletions(-)

diff --git a/go/main.go b/go/main.go
index 8481f29..f51a165 100644
--- a/go/main.go
+++ b/go/main.go
@@ -66,6 +66,13 @@ func extractDigest(s string) string {
 	return s
 }
 
+func normalizeImageTag(tag string) string {
+	if !strings.Contains(tag, ":") {
+		return tag + ":latest"
+	}
+	return tag
+}
+
 func checkImageUpdates() {
 	ctx := context.Background()
 	cli, err := client.NewClientWithOpts(client.FromEnv)
@@ -77,7 +84,6 @@ func checkImageUpdates() {
 
 	rc := regclient.New()
 
-	// Nur laufende Container abrufen
 	containers, err := cli.ContainerList(ctx, container.ListOptions{All: false})
 	if err != nil {
 		log.Printf("Fehler beim ContainerList: %v", err)
@@ -90,25 +96,28 @@ func checkImageUpdates() {
 		return
 	}
 
-	// RepoTag → Digest map
 	imageTagToDigest := make(map[string]string)
 	for _, img := range images {
 		for _, tag := range img.RepoTags {
+			normalizedTag := normalizeImageTag(tag)
 			if len(img.RepoDigests) > 0 {
-				imageTagToDigest[tag] = extractDigest(img.RepoDigests[0])
+				imageTagToDigest[normalizedTag] = extractDigest(img.RepoDigests[0])
 			} else {
-				imageTagToDigest[tag] = img.ID
+				imageTagToDigest[normalizedTag] = img.ID
 			}
 		}
 	}
-
-	for tag, digest := range imageTagToDigest {
-		log.Printf("imageTagToDigest: %s -> %s\n", tag, digest)
+	// Debug-Ausgabe aller bekannten imageTagToDigest
+	fmt.Println("DEBUG: Alle bekannten imageTagToDigest:")
+	for k, v := range imageTagToDigest {
+		fmt.Printf("  %s -> %s\n", k, v)
 	}
 
 	results := make([]ImageStatus, 0)
 	for _, ctr := range containers {
-		tag := ctr.Image
+		rawTag := ctr.Image
+		tag := normalizeImageTag(rawTag)
+
 		containerName := "unknown"
 		if len(ctr.Names) > 0 {
 			containerName = ctr.Names[0]
@@ -145,22 +154,21 @@ func checkImageUpdates() {
 				containerName, tag, localDigest, remoteDigest)
 		}
 
-		labelImg, labelTag := tag, "latest"
+		imageName, imageTag := tag, "latest"
 		if cp := strings.Split(tag, ":"); len(cp) == 2 {
-			labelImg, labelTag = cp[0], cp[1]
+			imageName, imageTag = cp[0], cp[1]
 		}
 
 		results = append(results, ImageStatus{
 			ContainerName:   containerName,
-			Image:           labelImg,
-			Tag:             labelTag,
+			Image:           imageName,
+			Tag:             imageTag,
 			UpdateAvailable: update,
 			LocalDigest:     localDigest,
 			RemoteDigest:    remoteDigest,
 		})
 	}
 
-	// Speichern in Cache
 	cache.Lock()
 	cache.Data = results
 	cache.LastCheck = time.Now()
@@ -175,7 +183,7 @@ func newImageUpdateCollector() *imageUpdateCollector {
 	return &imageUpdateCollector{
 		metric: prometheus.NewDesc(
 			"docker_image_update_available",
-			"Ob Update für das lokale Docker-Image eines laufenden Containers verfügbar ist (1 = Update, 0 = aktuell)",
+			"Ob ein Update für das verwendete Image eines laufenden Containers verfügbar ist (1 = Update)",
 			[]string{"container_name", "image", "tag"},
 			nil,
 		),
@@ -198,16 +206,15 @@ func (c *imageUpdateCollector) Collect(ch chan<- prometheus.Metric) {
 }
 
 func main() {
-	log.Printf("🚀 Docker Image Update Exporter gestartet (Intervall = %v)", interval)
+	log.Printf("🚀 Docker Image Update Exporter gestartet – Intervall: %v", interval)
 
-	// Hintergrundprozess zum Aktualisieren des Caches
 	go func() {
 		for {
 			checkImageUpdates()
 			time.Sleep(interval)
 		}
 	}()
-	checkImageUpdates() // initial
+	checkImageUpdates()
 
 	exporter := newImageUpdateCollector()
 	prometheus.MustRegister(exporter)