chore: refactor config center (#4339)

Signed-off-by: kevin <wanjunfeng@gmail.com>

core/configcenter/configurator.go

@@ -15,8 +15,8 @@ import (
 )
 
 var (
-	errorEmptyConfig         = errors.New("empty config value")
-	errorMissUnmarshalerType = errors.New("miss unmarshaler type")
+	errEmptyConfig            = errors.New("empty config value")
+	errMissingUnmarshalerType = errors.New("missing unmarshaler type")
 )
 
 // Configurator is the interface for configuration center.
@@ -32,19 +32,17 @@ type (
 	Config struct {
 		// Type is the value type, yaml, json or toml.
 		Type string `json:",default=yaml,options=[yaml,json,toml]"`
-		// Log indicates whether to log the configuration.
-		Log bool `json:",default=ture"`
+		// Log is the flag to control logging.
+		Log bool `json:",default=true"`
 	}
 
 	configCenter[T any] struct {
 		conf        Config
 		unmarshaler LoaderFn
-
-		subscriber subscriber.Subscriber
-
-		listeners []func()
-		lock      sync.Mutex
-		snapshot  atomic.Value
+		subscriber  subscriber.Subscriber
+		listeners   []func()
+		lock        sync.Mutex
+		snapshot    atomic.Value
 	}
 
 	value[T any] struct {
@@ -61,7 +59,6 @@ var _ Configurator[any] = (*configCenter[any])(nil)
 func MustNewConfigCenter[T any](c Config, subscriber subscriber.Subscriber) Configurator[T] {
 	cc, err := NewConfigCenter[T](c, subscriber)
 	logx.Must(err)
-
 	return cc
 }
 
@@ -76,9 +73,6 @@ func NewConfigCenter[T any](c Config, subscriber subscriber.Subscriber) (Configu
 		conf:        c,
 		unmarshaler: unmarshaler,
 		subscriber:  subscriber,
-		listeners:   nil,
-		lock:        sync.Mutex{},
-		snapshot:    atomic.Value{},
 	}
 
 	if err := cc.loadConfig(); err != nil {
@@ -105,10 +99,10 @@ func (c *configCenter[T]) AddListener(listener func()) {
 
 // GetConfig return structured config.
 func (c *configCenter[T]) GetConfig() (T, error) {
-	var r T
 	v := c.value()
-	if v == nil || len(v.data) < 1 {
-		return r, errorEmptyConfig
+	if v == nil || len(v.data) == 0 {
+		var empty T
+		return empty, errEmptyConfig
 	}
 
 	return v.marshalData, v.err
@@ -141,7 +135,9 @@ func (c *configCenter[T]) loadConfig() error {
 }
 
 func (c *configCenter[T]) onChange() {
-	_ = c.loadConfig()
+	if err := c.loadConfig(); err != nil {
+		return
+	}
 
 	c.lock.Lock()
 	listeners := make([]func(), len(c.listeners))
@@ -165,40 +161,39 @@ func (c *configCenter[T]) genValue(data string) *value[T] {
 	v := &value[T]{
 		data: data,
 	}
-	if len(data) <= 0 {
+	if len(data) == 0 {
 		return v
 	}
 
 	t := reflect.TypeOf(v.marshalData)
 	// if the type is nil, it means that the user has not set the type of the configuration.
 	if t == nil {
-		v.err = errorMissUnmarshalerType
+		v.err = errMissingUnmarshalerType
 		return v
 	}
 
 	t = mapping.Deref(t)
-
 	switch t.Kind() {
 	case reflect.Struct, reflect.Array, reflect.Slice:
-		err := c.unmarshaler([]byte(data), &v.marshalData)
-		if err != nil {
+		if err := c.unmarshaler([]byte(data), &v.marshalData); err != nil {
 			v.err = err
 			if c.conf.Log {
-				logx.Errorf("ConfigCenter unmarshal configuration failed, err: %+v, content [%s]", err.Error(), data)
+				logx.Errorf("ConfigCenter unmarshal configuration failed, err: %+v, content [%s]",
+					err.Error(), data)
 			}
 		}
 	case reflect.String:
 		if str, ok := any(data).(T); ok {
 			v.marshalData = str
 		} else {
-			v.err = errorMissUnmarshalerType
+			v.err = errMissingUnmarshalerType
 		}
 	default:
 		if c.conf.Log {
 			logx.Errorf("ConfigCenter unmarshal configuration missing unmarshaler for type: %s, content [%s]",
 				t.Kind(), data)
 		}
-		v.err = errorMissUnmarshalerType
+		v.err = errMissingUnmarshalerType
 	}
 
 	return v

core/configcenter/configurator_test.go

@@ -150,7 +150,7 @@ func TestConfigCenter_AddListener(t *testing.T) {
 func TestConfigCenter_genValue(t *testing.T) {
 	t.Run("data is empty", func(t *testing.T) {
 		c := &configCenter[string]{
-			unmarshaler: defaultRegistry.unmarshalers["json"],
+			unmarshaler: registry.unmarshalers["json"],
 			conf:        Config{Log: true},
 		}
 		v := c.genValue("")
@@ -159,25 +159,25 @@ func TestConfigCenter_genValue(t *testing.T) {
 
 	t.Run("invalid template type", func(t *testing.T) {
 		c := &configCenter[any]{
-			unmarshaler: defaultRegistry.unmarshalers["json"],
+			unmarshaler: registry.unmarshalers["json"],
 			conf:        Config{Log: true},
 		}
 		v := c.genValue("xxxx")
-		assert.Equal(t, errorMissUnmarshalerType, v.err)
+		assert.Equal(t, errMissingUnmarshalerType, v.err)
 	})
 
 	t.Run("unsupported template type", func(t *testing.T) {
 		c := &configCenter[int]{
-			unmarshaler: defaultRegistry.unmarshalers["json"],
+			unmarshaler: registry.unmarshalers["json"],
 			conf:        Config{Log: true},
 		}
 		v := c.genValue("1")
-		assert.Equal(t, errorMissUnmarshalerType, v.err)
+		assert.Equal(t, errMissingUnmarshalerType, v.err)
 	})
 
 	t.Run("supported template string type", func(t *testing.T) {
 		c := &configCenter[string]{
-			unmarshaler: defaultRegistry.unmarshalers["json"],
+			unmarshaler: registry.unmarshalers["json"],
 			conf:        Config{Log: true},
 		}
 		v := c.genValue("12345")
@@ -189,7 +189,7 @@ func TestConfigCenter_genValue(t *testing.T) {
 		c := &configCenter[struct {
 			Name string `json:"name"`
 		}]{
-			unmarshaler: defaultRegistry.unmarshalers["json"],
+			unmarshaler: registry.unmarshalers["json"],
 			conf:        Config{Log: true},
 		}
 		v := c.genValue(`{"name":"new name}`)
@@ -201,7 +201,7 @@ func TestConfigCenter_genValue(t *testing.T) {
 		c := &configCenter[struct {
 			Name string `json:"name"`
 		}]{
-			unmarshaler: defaultRegistry.unmarshalers["json"],
+			unmarshaler: registry.unmarshalers["json"],
 			conf:        Config{Log: true},
 		}
 		v := c.genValue(`{"name":"new name"}`)

core/configcenter/subscriber/etcd.go

@@ -12,30 +12,19 @@ type (
 	}
 
 	// EtcdConf is the configuration for etcd.
-	EtcdConf discov.EtcdConf
+	EtcdConf = discov.EtcdConf
 )
 
 // MustNewEtcdSubscriber returns an etcd Subscriber, exits on errors.
 func MustNewEtcdSubscriber(conf EtcdConf) Subscriber {
 	s, err := NewEtcdSubscriber(conf)
 	logx.Must(err)
-
 	return s
 }
 
 // NewEtcdSubscriber returns an etcd Subscriber.
 func NewEtcdSubscriber(conf EtcdConf) (Subscriber, error) {
-	var opts = []discov.SubOption{
-		discov.WithDisablePrefix(),
-	}
-	if len(conf.User) != 0 {
-		opts = append(opts, discov.WithSubEtcdAccount(conf.User, conf.Pass))
-	}
-	if len(conf.CertFile) != 0 || len(conf.CertKeyFile) != 0 || len(conf.CACertFile) != 0 {
-		opts = append(opts,
-			discov.WithSubEtcdTLS(conf.CertFile, conf.CertKeyFile, conf.CACertFile, conf.InsecureSkipVerify))
-	}
-
+	opts := buildSubOptions(conf)
 	s, err := discov.NewSubscriber(conf.Hosts, conf.Key, opts...)
 	if err != nil {
 		return nil, err
@@ -44,6 +33,23 @@ func NewEtcdSubscriber(conf EtcdConf) (Subscriber, error) {
 	return &etcdSubscriber{Subscriber: s}, nil
 }
 
+// buildSubOptions constructs the options for creating a new etcd subscriber.
+func buildSubOptions(conf EtcdConf) []discov.SubOption {
+	opts := []discov.SubOption{
+		discov.WithExactMatch(),
+	}
+
+	if len(conf.User) > 0 {
+		opts = append(opts, discov.WithSubEtcdAccount(conf.User, conf.Pass))
+	}
+	if len(conf.CertFile) > 0 || len(conf.CertKeyFile) > 0 || len(conf.CACertFile) > 0 {
+		opts = append(opts, discov.WithSubEtcdTLS(conf.CertFile, conf.CertKeyFile,
+			conf.CACertFile, conf.InsecureSkipVerify))
+	}
+
+	return opts
+}
+
 // AddListener adds a listener to the subscriber.
 func (s *etcdSubscriber) AddListener(listener func()) error {
 	s.Subscriber.AddListener(listener)
@@ -53,8 +59,9 @@ func (s *etcdSubscriber) AddListener(listener func()) error {
 // Value returns the value of the subscriber.
 func (s *etcdSubscriber) Value() (string, error) {
 	vs := s.Subscriber.Values()
-	if len(vs) != 0 {
+	if len(vs) > 0 {
 		return vs[len(vs)-1], nil
 	}
+
 	return "", nil
 }

core/configcenter/unmarshaler.go

@@ -6,41 +6,36 @@ import (
 	"github.com/zeromicro/go-zero/core/conf"
 )
 
+var registry = &unmarshalerRegistry{
+	unmarshalers: map[string]LoaderFn{
+		"json": conf.LoadFromJsonBytes,
+		"toml": conf.LoadFromTomlBytes,
+		"yaml": conf.LoadFromYamlBytes,
+	},
+}
+
 type (
+	// LoaderFn is the function type for loading configuration.
+	LoaderFn func([]byte, any) error
+
 	// unmarshalerRegistry is the registry for unmarshalers.
 	unmarshalerRegistry struct {
 		unmarshalers map[string]LoaderFn
-
-		mu sync.RWMutex
+		mu           sync.RWMutex
 	}
-
-	// LoaderFn is the function type for loading configuration.
-	LoaderFn func([]byte, any) error
 )
 
-var defaultRegistry *unmarshalerRegistry
-
-func init() {
-	defaultRegistry = &unmarshalerRegistry{
-		unmarshalers: map[string]LoaderFn{
-			"json": conf.LoadFromJsonBytes,
-			"toml": conf.LoadFromTomlBytes,
-			"yaml": conf.LoadFromYamlBytes,
-		},
-	}
-}
-
 // RegisterUnmarshaler registers an unmarshaler.
 func RegisterUnmarshaler(name string, fn LoaderFn) {
-	defaultRegistry.mu.Lock()
-	defaultRegistry.unmarshalers[name] = fn
-	defaultRegistry.mu.Unlock()
+	registry.mu.Lock()
+	defer registry.mu.Unlock()
+	registry.unmarshalers[name] = fn
 }
 
 // Unmarshaler returns the unmarshaler by name.
 func Unmarshaler(name string) (LoaderFn, bool) {
-	defaultRegistry.mu.RLock()
-	fn, ok := defaultRegistry.unmarshalers[name]
-	defaultRegistry.mu.RUnlock()
+	registry.mu.RLock()
+	defer registry.mu.RUnlock()
+	fn, ok := registry.unmarshalers[name]
 	return fn, ok
 }

core/discov/internal/registry.go

@@ -46,7 +46,7 @@ func (r *Registry) GetConn(endpoints []string) (EtcdClient, error) {
 }
 
 // Monitor monitors the key on given etcd endpoints, notify with the given UpdateListener.
-func (r *Registry) Monitor(endpoints []string, key string, l UpdateListener, disablePrefix bool) error {
+func (r *Registry) Monitor(endpoints []string, key string, l UpdateListener, exactMatch bool) error {
 	c, exists := r.getCluster(endpoints)
 	// if exists, the existing values should be updated to the listener.
 	if exists {
@@ -56,7 +56,7 @@ func (r *Registry) Monitor(endpoints []string, key string, l UpdateListener, dis
 		}
 	}
 
-	return c.monitor(key, l, disablePrefix)
+	return c.monitor(key, l, exactMatch)
 }
 
 func (r *Registry) getCluster(endpoints []string) (c *cluster, exists bool) {
@@ -80,14 +80,14 @@ func (r *Registry) getCluster(endpoints []string) (c *cluster, exists bool) {
 }
 
 type cluster struct {
-	endpoints     []string
-	key           string
-	values        map[string]map[string]string
-	listeners     map[string][]UpdateListener
-	watchGroup    *threading.RoutineGroup
-	done          chan lang.PlaceholderType
-	lock          sync.RWMutex
-	disablePrefix bool
+	endpoints  []string
+	key        string
+	values     map[string]map[string]string
+	listeners  map[string][]UpdateListener
+	watchGroup *threading.RoutineGroup
+	done       chan lang.PlaceholderType
+	lock       sync.RWMutex
+	exactMatch bool
 }
 
 func newCluster(endpoints []string) *cluster {
@@ -226,7 +226,7 @@ func (c *cluster) load(cli EtcdClient, key string) int64 {
 	for {
 		var err error
 		ctx, cancel := context.WithTimeout(c.context(cli), RequestTimeout)
-		if c.disablePrefix {
+		if c.exactMatch {
 			resp, err = cli.Get(ctx, key)
 		} else {
 			resp, err = cli.Get(ctx, makeKeyPrefix(key), clientv3.WithPrefix())
@@ -254,10 +254,10 @@ func (c *cluster) load(cli EtcdClient, key string) int64 {
 	return resp.Header.Revision
 }
 
-func (c *cluster) monitor(key string, l UpdateListener, disablePrefix bool) error {
+func (c *cluster) monitor(key string, l UpdateListener, exactMatch bool) error {
 	c.lock.Lock()
 	c.listeners[key] = append(c.listeners[key], l)
-	c.disablePrefix = disablePrefix
+	c.exactMatch = exactMatch
 	c.lock.Unlock()
 
 	cli, err := c.getClient()
@@ -328,7 +328,7 @@ func (c *cluster) watchStream(cli EtcdClient, key string, rev int64) error {
 		ops      []clientv3.OpOption
 		watchKey = key
 	)
-	if !c.disablePrefix {
+	if !c.exactMatch {
 		watchKey = makeKeyPrefix(key)
 		ops = append(ops, clientv3.WithPrefix())
 	}