refactor!: simplify etcd path handling to single base path

- Remove support for multiple etcd paths via scrape-etcd-paths flag
- Refactor getScrapeTargets to use single etcd path
- Extract service name from last segment of etcd path
- Clean up whitespace and formatting

cmd/promster/main.go

@@ -126,17 +126,16 @@ func reloadPrometheus() error {
 	}
 }
 
-
 func parseAddress(address string) (host string, metricsPath string) {
 	// Default metrics path
 	metricsPath = "/metrics"
-	
+
 	// Remove scheme (http:// or https://)
 	if strings.Contains(address, "://") {
 		parts := strings.SplitN(address, "://", 2)
 		address = parts[1]
 	}
-	
+
 	// Extract path if exists
 	if strings.Contains(address, "/") {
 		parts := strings.SplitN(address, "/", 2)
@@ -147,64 +146,64 @@ func parseAddress(address string) (host string, metricsPath string) {
 	} else {
 		host = address
 	}
-	
+
 	return host, metricsPath
 }
 
-func getScrapeTargets(registry *etcdregistry.EtcdRegistry, scrapeEtcdPaths []string) []ServiceGroup {
+func getScrapeTargets(registry *etcdregistry.EtcdRegistry, etcdPath string) []ServiceGroup {
 	// Map to group targets by service name and auth
 	groupMap := make(map[string]*ServiceGroup)
 
-	for _, path := range scrapeEtcdPaths {
-		nodes, err := registry.GetServiceNodes(path)
-		if err != nil {
-			logrus.Warnf("Failed to get service nodes for path %s: %v", path, err)
-			continue
+	nodes, err := registry.GetServiceNodes(etcdPath)
+	if err != nil {
+		logrus.Warnf("Failed to get service nodes for path %s: %v", etcdPath, err)
+		return nil
+	}
+
+	for _, node := range nodes {
+		// Use the last part of the path as the service name
+		pathParts := strings.Split(etcdPath, "/")
+		serviceName := pathParts[len(pathParts)-1]
+		address, metricsPath := parseAddress(node.Info["address"])
+
+		// Create auth key for grouping
+		authKey := ""
+		if password, ok := node.Info["password"]; ok {
+			username := node.Info["username"]
+			if username == "" {
+				username = "prometheus" // default username
+			}
+			authKey = username + ":" + password
 		}
 
-		for _, node := range nodes {
-			serviceName := path
-			address, metricsPath := parseAddress(node.Info["address"])
+		// Create group key
+		groupKey := serviceName + "|" + authKey
 
-			// Create auth key for grouping
-			authKey := ""
-			if password, ok := node.Info["password"]; ok {
-				username := node.Info["username"]
-				if username == "" {
-					username = "prometheus" // default username
-				}
-				authKey = username + ":" + password
+		group, exists := groupMap[groupKey]
+		if !exists {
+			group = &ServiceGroup{
+				Name:        serviceName,
+				Targets:     make([]string, 0),
+				MetricsPath: metricsPath,
+				NodeID:      node.Name,
 			}
 
-			// Create group key
-			groupKey := serviceName + "|" + authKey
-
-			group, exists := groupMap[groupKey]
-			if !exists {
-				group = &ServiceGroup{
-					Name:        serviceName,
-					Targets:     make([]string, 0),
-					MetricsPath: metricsPath,
-					NodeID:      node.Name,
+			// Only set auth if credentials exist
+			if authKey != "" {
+				username := node.Info["username"]
+				if username == "" {
+					username = "prometheus"
 				}
-
-				// Only set auth if credentials exist
-				if authKey != "" {
-					username := node.Info["username"]
-					if username == "" {
-						username = "prometheus"
-					}
-					group.BasicAuth = &BasicAuth{
-						Username: username,
-						Password: node.Info["password"],
-					}
+				group.BasicAuth = &BasicAuth{
+					Username: username,
+					Password: node.Info["password"],
 				}
-
-				groupMap[groupKey] = group
 			}
 
-			group.Targets = append(group.Targets, address)
+			groupMap[groupKey] = group
 		}
+
+		group.Targets = append(group.Targets, address)
 	}
 
 	// Convert map to slice
@@ -252,7 +251,7 @@ var (
 	configFile         string
 )
 
-func monitorTargets(ctx context.Context, registry *etcdregistry.EtcdRegistry, scrapeEtcdPaths []string) error {
+func monitorTargets(ctx context.Context, registry *etcdregistry.EtcdRegistry, etcdPath string) error {
 	ticker := time.NewTicker(5 * time.Second)
 	defer ticker.Stop()
 
@@ -264,7 +263,7 @@ func monitorTargets(ctx context.Context, registry *etcdregistry.EtcdRegistry, sc
 	for {
 		select {
 		case <-ticker.C:
-			serviceGroups := getScrapeTargets(registry, scrapeEtcdPaths)
+			serviceGroups := getScrapeTargets(registry, etcdPath)
 
 			targetsMu.Lock()
 			if !reflect.DeepEqual(serviceGroups, previousGroups) {
@@ -304,7 +303,6 @@ func run(ctx context.Context, cmd *cli.Command) error {
 	// Get flag values
 	etcdURLScrape := cmd.String("scrape-etcd-url")
 	etcdBasePath := cmd.String("etcd-base-path")
-	scrapeEtcdPaths := strings.Split(cmd.String("scrape-etcd-paths"), ",")
 	scrapeInterval = cmd.String("scrape-interval")
 	scrapeTimeout = cmd.String("scrape-timeout")
 	evaluationInterval = cmd.String("evaluation-interval")
@@ -346,15 +344,15 @@ func run(ctx context.Context, cmd *cli.Command) error {
 	if rulesFile == "" {
 		rulesFile = "/rules.yml"
 	}
-	
+
 	if err := createRulesFromENV(rulesFile); err != nil {
 		return fmt.Errorf("failed to create rules: %w", err)
 	}
 
 	ctx, cancel := signal.NotifyContext(ctx, os.Interrupt)
 	defer cancel()
 
-	return monitorTargets(ctx, registry, scrapeEtcdPaths)
+	return monitorTargets(ctx, registry, etcdBasePath)
 }
 
 func main() {
@@ -380,12 +378,6 @@ func main() {
 				Required: true,
 				Sources:  cli.EnvVars("PROMSTER_ETCD_BASE_PATH"),
 			},
-			&cli.StringFlag{
-				Name:     "scrape-etcd-paths",
-				Usage:    "Comma-separated list of base ETCD paths for getting servers to be scrapped",
-				Required: true,
-				Sources:  cli.EnvVars("PROMSTER_SCRAPE_ETCD_PATHS"),
-			},
 			&cli.StringFlag{
 				Name:    "scrape-interval",
 				Value:   "30s",