fix(sd): default namespace is graphite

sd/nginx/nginx.go

@@ -15,14 +15,15 @@ import (
 )
 
 type ErrInvalidKey struct {
+	key string
 	val string
 }
 
 func (e ErrInvalidKey) Error() string {
 	if e.val == "" {
-		return "list key is invalid"
+		return "list key '" + e.key + "' is invalid"
 	}
-	return "list key is invalid: '" + e.val + "'"
+	return "list key '" + e.key + "' is invalid: '" + e.val + "'"
 }
 
 var (
@@ -50,6 +51,7 @@ func splitNode(node string) (dc, host, listen string, ok bool) {
 type Nginx struct {
 	weight     int64
 	hostname   string
+	namespace  string
 	body       []byte
 	backupBody []byte
 	url        stringutils.Builder
@@ -60,21 +62,24 @@ type Nginx struct {
 }
 
 func New(url, namespace, hostname string, logger *zap.Logger) *Nginx {
+	if namespace == "" {
+		namespace = "graphite"
+	}
 	sd := &Nginx{
 		logger:     logger,
 		body:       make([]byte, 128),
 		backupBody: []byte(`{"backup":1,"max_fails":0}`),
-		nsEnd:      "upstreams/" + namespace + "/",
 		hostname:   hostname,
+		namespace:  namespace,
+		nsEnd:      "upstreams/" + namespace + "/",
 	}
 	sd.setWeight(0)
 
 	sd.url.WriteString(url)
 	sd.url.WriteByte('/')
-	if namespace != "" {
-		sd.url.WriteString(namespace)
-		sd.url.WriteByte('/')
-	}
+
+	sd.url.WriteString(namespace)
+	sd.url.WriteByte('/')
 	sd.pos = sd.url.Len()
 
 	return sd
@@ -109,13 +114,13 @@ func (sd *Nginx) List() (nodes []string, err error) {
 			if i, ok := jNode["Key"]; ok {
 				if s, ok := i.(string); ok {
 					if strings.HasPrefix(s, sd.nsEnd) {
-						s = s[len(sd.nsEnd):]
+						s = s[len(sd.namespace)+2:]
 						_, host, _, ok := splitNode(s)
 						if ok && host == sd.hostname {
 							nodes = append(nodes, s)
 						}
 					} else {
-						return nil, ErrInvalidKey{s}
+						return nil, ErrInvalidKey{key: sd.nsEnd, val: s}
 					}
 				} else {
 					return nil, ErrNoKey
@@ -147,8 +152,8 @@ func (sd *Nginx) ListMap() (nodes map[string]string, err error) {
 		if jNode, ok := i.(map[string]interface{}); ok {
 			if i, ok := jNode["Key"]; ok {
 				if s, ok := i.(string); ok {
-					if strings.HasPrefix(s, sd.nsEnd) {
-						s = s[len(sd.nsEnd):]
+					if strings.HasPrefix(s, sd.namespace) {
+						s = s[len(sd.namespace)+2:]
 						_, host, _, ok := splitNode(s)
 						if ok && host == sd.hostname {
 							if i, ok := jNode["Value"]; ok {
@@ -166,7 +171,7 @@ func (sd *Nginx) ListMap() (nodes map[string]string, err error) {
 							}
 						}
 					} else {
-						return nil, ErrInvalidKey{s}
+						return nil, ErrInvalidKey{key: sd.nsEnd, val: s}
 					}
 				} else {
 					return nil, ErrNoKey
@@ -199,7 +204,7 @@ func (sd *Nginx) Nodes() (nodes []utils.KV, err error) {
 			if i, ok := jNode["Key"]; ok {
 				if s, ok := i.(string); ok {
 					if strings.HasPrefix(s, sd.nsEnd) {
-						s = s[len(sd.nsEnd):]
+						s = s[len(sd.namespace)+2:]
 						kv := utils.KV{Key: s}
 						if i, ok := jNode["Value"]; ok {
 							if v, ok := i.(string); ok {
@@ -222,7 +227,7 @@ func (sd *Nginx) Nodes() (nodes []utils.KV, err error) {
 						}
 						nodes = append(nodes, kv)
 					} else {
-						return nil, ErrInvalidKey{s}
+						return nil, ErrInvalidKey{key: sd.nsEnd, val: s}
 					}
 				} else {
 					return nil, ErrNoKey