feat(tags): support inject default tags from env (#25)

README.md

@@ -175,6 +175,7 @@ func main() {
 | serverAddr               | 127.0.0.1                          | nacos server address              |
 | serverPort               | 8848                               | nacos server port                 |
 | namespace                 |                                    | the namespaceId of nacos          |
+| NACOS_ENV_TAGS           | ""                                  | support inject default tags|
 
 ### More Info
 

README_CN.md

@@ -175,6 +175,7 @@ func main() {
 | serverAddr               | 127.0.0.1                          | nacos 服务器地址 |
 | serverPort               | 8848                               | nacos 服务器端口            |
 | namespace                 |                                    | nacos 中的 namespace Id |
+| NACOS_ENV_TAGS           | ""                                 | 支持注入默认 nacos tags|
 
 ### 更多信息
 

nacos/env.go

@@ -17,19 +17,43 @@ package nacos
 import (
 	"os"
 	"strconv"
+	"strings"
 
 	"github.com/cloudwego/kitex/pkg/klog"
 )
 
 const (
 	NACOS_ENV_SERVER_ADDR     = "serverAddr"
 	NACOS_ENV_PORT            = "serverPort"
+	NACOS_ENV_TAGS            = "NACOS_ENV_TAGS"
 	NACOS_ENV_NAMESPACE_ID    = "namespace"
 	NACOS_DEFAULT_SERVER_ADDR = "127.0.0.1"
 	NACOS_DEFAULT_PORT        = 8848
 	NACOS_DEFAULT_REGIONID    = "cn-hangzhou"
 )
 
+// Tags providers the default tags to inject nacos.
+var Tags map[string]string
+
+func init() {
+	Tags = parseTags(os.Getenv(NACOS_ENV_TAGS))
+}
+
+func parseTags(tags string) map[string]string {
+	if len(tags) == 0 {
+		return nil
+	}
+	out := map[string]string{}
+	parts := strings.Split(tags, ",")
+	for _, part := range parts {
+		tag := strings.Split(part, "=")
+		if len(tag) == 2 {
+			out[tag[0]] = tag[1]
+		}
+	}
+	return out
+}
+
 // NacosPort Get Nacos port from environment variables
 func NacosPort() int64 {
 	portText := os.Getenv(NACOS_ENV_PORT)

nacos/env_test.go

@@ -26,3 +26,10 @@ func TestEnvFunc(t *testing.T) {
 	assert.Equal(t, "127.0.0.1", NacosAddr())
 	assert.Equal(t, "public", NacosNameSpaceId())
 }
+
+func TestParseTags(t *testing.T) {
+	assert.Equal(t, parseTags("k1=v1,k2=v2"), map[string]string{
+		"k1": "v1",
+		"k2": "v2",
+	})
+}

registry/registry.go

@@ -91,14 +91,15 @@ func (n *nacosRegistry) Register(info *registry.Info) error {
 			return fmt.Errorf("parse registry info addr error: %w", err)
 		}
 	}
+
 	_, e := n.cli.RegisterInstance(vo.RegisterInstanceParam{
 		Ip:          host,
 		Port:        uint64(p),
 		ServiceName: info.ServiceName,
 		Weight:      float64(info.Weight),
 		Enable:      true,
 		Healthy:     true,
-		Metadata:    info.Tags,
+		Metadata:    mergeTags(info.Tags, nacos.Tags),
 		GroupName:   n.opts.group,
 		ClusterName: n.opts.cluster,
 		Ephemeral:   true,
@@ -171,3 +172,20 @@ func (n *nacosRegistry) Deregister(info *registry.Info) error {
 	}
 	return nil
 }
+
+// should not modify the source data.
+func mergeTags(ts ...map[string]string) map[string]string {
+	if len(ts) == 0 {
+		return nil
+	}
+	if len(ts) == 1 {
+		return ts[0]
+	}
+	tags := map[string]string{}
+	for _, t := range ts {
+		for k, v := range t {
+			tags[k] = v
+		}
+	}
+	return tags
+}

registry/registry_test.go

@@ -302,3 +302,29 @@ func TestNacosMultipleInstancesWithDefaultNacosRegistry(t *testing.T) {
 		}
 	}
 }
+
+func TestMergeTags(t *testing.T) {
+	t1 := map[string]string{
+		"k1": "v1",
+		"k2": "v2",
+	}
+	t2 := map[string]string{
+		"k3": "v3",
+		"k4": "v4",
+	}
+	merged := mergeTags(t1, t2)
+	assert.Equal(t, merged, map[string]string{
+		"k1": "v1",
+		"k2": "v2",
+		"k3": "v3",
+		"k4": "v4",
+	})
+	assert.Equal(t, t1, map[string]string{
+		"k1": "v1",
+		"k2": "v2",
+	})
+	assert.Equal(t, t2, map[string]string{
+		"k3": "v3",
+		"k4": "v4",
+	})
+}