feat: introduce pod-name flag specifically for kubernetes

Author: helder-moreira

cmd/cosmoseed/config.go

@@ -14,8 +14,8 @@ const (
 )
 
 var (
-	home, chainID, seeds, logLevel, nodeKeyFile, externalAddress string
-	showVersion, showNodeID, configReadOnly                      bool
+	home, chainID, seeds, logLevel, externalAddress, podName string
+	showVersion, showNodeID, configReadOnly                  bool
 )
 
 func init() {
@@ -42,15 +42,19 @@ func init() {
 		utils.GetString("LOG_LEVEL", "info"),
 		"logging level",
 	)
-	flag.StringVar(&nodeKeyFile,
-		"node-key-file",
-		utils.GetString("NODE_KEY_FILE", ""),
-		"override node key file on config.yaml",
-	)
 	flag.StringVar(&externalAddress,
 		"external-address",
 		utils.GetString("EXTERNAL_ADDRESS", ""),
-		"external address to use in format '<host>:<port>'",
+		"external address to use in format '<host>:<port>'. "+
+			"When pod-name is set, this can be a list separated by comma and index will be extracted "+
+			"from pod name to chose the correct address (useful on kubernetes StatefulSets)",
+	)
+	flag.StringVar(&podName,
+		"pod-name",
+		utils.GetString("POD_NAME", ""),
+		"name of the pod when running on kubernetes. When set, node-key-file will be set to pod "+
+			"name and index will be extracted from it to pick the right address from"+
+			"external-address list (comma separated) (useful on kubernetes StatefulSets)",
 	)
 
 	flag.BoolVar(&showVersion, "version", false, "print version and exit")

cmd/cosmoseed/main.go

@@ -5,6 +5,8 @@ import (
 	"fmt"
 	"os"
 	"path"
+	"strconv"
+	"strings"
 
 	cosmoseed2 "github.com/NibiruChain/cosmoseed/pkg/cosmoseed"
 )
@@ -49,14 +51,21 @@ func main() {
 		cfg.LogLevel = logLevel
 	}
 
-	if nodeKeyFile != "" {
-		cfg.NodeKeyFile = nodeKeyFile
-	}
-
 	if externalAddress != "" {
 		cfg.ExternalAddress = externalAddress
 	}
 
+	if podName != "" {
+		cfg.NodeKeyFile = podName
+		if externalAddress != "" {
+			idx, _ := extractIndexFromPodName(podName)
+			parts := strings.Split(externalAddress, ",")
+			if len(parts) > idx {
+				cfg.ExternalAddress = parts[idx]
+			}
+		}
+	}
+
 	seeder, err := cosmoseed2.NewSeeder(home, cfg)
 	if err != nil {
 		panic(err)
@@ -71,3 +80,16 @@ func main() {
 		panic(err)
 	}
 }
+
+func extractIndexFromPodName(podName string) (int, error) {
+	parts := strings.Split(podName, "-")
+	if len(parts) == 0 {
+		return 0, fmt.Errorf("invalid pod name: %s", podName)
+	}
+	indexStr := parts[len(parts)-1]
+	index, err := strconv.Atoi(indexStr)
+	if err != nil {
+		return 0, fmt.Errorf("failed to parse index from pod name %q: %w", podName, err)
+	}
+	return index, nil
+}