From 3fbef4fd4b38165f3c876ec041542aae6ae3bb61 Mon Sep 17 00:00:00 2001
From: Vladimir Dementyev <palkan@hey.com>
Date: Tue, 31 Oct 2023 07:55:58 -0700
Subject: [PATCH] fix: add server_name to enats

---
 broker/nats.go  |  2 +-
 enats/config.go |  1 +
 enats/enats.go  | 47 +++++++++++++++++++++++++++++++++++++----------
 3 files changed, 39 insertions(+), 11 deletions(-)

diff --git a/broker/nats.go b/broker/nats.go
index 44d287eb..754021e6 100644
--- a/broker/nats.go
+++ b/broker/nats.go
@@ -167,7 +167,7 @@ func (n *NATS) Shutdown(ctx context.Context) error {
 func (n *NATS) Announce() string {
 	brokerParams := fmt.Sprintf("(history limit: %d, history ttl: %ds, sessions ttl: %ds)", n.conf.HistoryLimit, n.conf.HistoryTTL, n.conf.SessionsTTL)
 
-	return fmt.Sprintf("Starting NATS broker: %s %s", n.nconf.Servers, brokerParams)
+	return fmt.Sprintf("Using NATS broker: %s %s", n.nconf.Servers, brokerParams)
 }
 
 func (n *NATS) Epoch() string {
diff --git a/enats/config.go b/enats/config.go
index 2068a675..1d48bfb3 100644
--- a/enats/config.go
+++ b/enats/config.go
@@ -4,6 +4,7 @@ package enats
 type Config struct {
 	Debug            bool
 	Trace            bool
+	Name             string
 	ServiceAddr      string
 	ClusterAddr      string
 	ClusterName      string
diff --git a/enats/enats.go b/enats/enats.go
index 1c93f988..34c00dcb 100644
--- a/enats/enats.go
+++ b/enats/enats.go
@@ -9,10 +9,12 @@ import (
 	"net/url"
 	"strconv"
 	"strings"
+	"sync"
 	"time"
 
 	"github.com/apex/log"
 	"github.com/joomcode/errorx"
+	gonanoid "github.com/matoous/go-nanoid"
 	"github.com/nats-io/nats-server/v2/server"
 	"github.com/nats-io/nats.go"
 )
@@ -25,6 +27,9 @@ const (
 type Service struct {
 	config *Config
 	server *server.Server
+	name   string
+
+	mu sync.Mutex
 }
 
 // LogEntry represents LoggerV2 decorator for nats server logger
@@ -88,15 +93,16 @@ func (s *Service) Start() error {
 	}
 
 	opts := &server.Options{
-		Host:      u.Hostname(),
-		Port:      int(port),
-		Debug:     s.config.Debug,
-		Trace:     s.config.Trace,
-		Cluster:   clusterOpts,
-		Gateway:   gatewayOpts,
-		Routes:    routes,
-		NoSigs:    true,
-		JetStream: s.config.JetStream,
+		Host:       u.Hostname(),
+		Port:       int(port),
+		Debug:      s.config.Debug,
+		Trace:      s.config.Trace,
+		ServerName: s.serverName(),
+		Cluster:    clusterOpts,
+		Gateway:    gatewayOpts,
+		Routes:     routes,
+		NoSigs:     true,
+		JetStream:  s.config.JetStream,
 	}
 
 	if s.config.StoreDir != "" {
@@ -132,8 +138,10 @@ func (s *Service) WaitReady() error {
 func (s *Service) Description() string {
 	var builder strings.Builder
 
+	builder.WriteString(fmt.Sprintf("server_name: %s", s.serverName()))
+
 	if s.config.ClusterAddr != "" {
-		builder.WriteString(fmt.Sprintf("cluster: %s, cluster_name: %s", s.config.ClusterAddr, s.config.ClusterName))
+		builder.WriteString(fmt.Sprintf(", cluster: %s, cluster_name: %s", s.config.ClusterAddr, s.config.ClusterName))
 	}
 
 	if s.config.Routes != nil {
@@ -269,3 +277,22 @@ func parseAddress(addr string) (string, int, error) {
 
 	return uri.Hostname(), int(port), nil
 }
+
+func (s *Service) serverName() string {
+	s.mu.Lock()
+	defer s.mu.Unlock()
+
+	if s.name != "" {
+		return s.name
+	}
+
+	if s.config.Name != "" {
+		s.name = s.config.Name
+		return s.name
+	}
+
+	suf, _ := gonanoid.Nanoid(3) // nolint: errcheck
+
+	s.name = strings.ReplaceAll(strings.ReplaceAll(s.config.ServiceAddr, ":", "-"), "/", "") + "-" + suf
+	return s.name
+}