services/introspection: support to show introspection grpc service

Signed-off-by: Iceber Gu <wei.cai-nat@daocloud.io>

services/introspection/local.go

@@ -41,12 +41,9 @@ func init() {
 		ID:       services.IntrospectionService,
 		Requires: []plugin.Type{},
 		InitFn: func(ic *plugin.InitContext) (interface{}, error) {
-			// this service works by using the plugin context up till the point
-			// this service is initialized. Since we require this service last,
-			// it should provide the full set of plugins.
-			pluginsPB := pluginsToPB(ic.GetAll())
+			// this service fetches all plugins through the plugin set of the plugin context
 			return &Local{
-				plugins: pluginsPB,
+				plugins: ic.Plugins(),
 				root:    ic.Root,
 			}, nil
 		},
@@ -55,19 +52,19 @@ func init() {
 
 // Local is a local implementation of the introspection service
 type Local struct {
-	mu      sync.Mutex
-	plugins []api.Plugin
-	root    string
+	mu        sync.Mutex
+	root      string
+	plugins   *plugin.Set
+	pluginsPB []api.Plugin
 }
 
 var _ = (api.IntrospectionClient)(&Local{})
 
 // UpdateLocal updates the local introspection service
-func (l *Local) UpdateLocal(root string, plugins []api.Plugin) {
+func (l *Local) UpdateLocal(root string) {
 	l.mu.Lock()
 	defer l.mu.Unlock()
 	l.root = root
-	l.plugins = plugins
 }
 
 // Plugins returns the locally defined plugins
@@ -93,9 +90,16 @@ func (l *Local) Plugins(ctx context.Context, req *api.PluginsRequest, _ ...grpc.
 }
 
 func (l *Local) getPlugins() []api.Plugin {
+	if !plugin.AreRegisteredPluginsInitialized(l.plugins) {
+		return pluginsToPB(l.plugins.GetAll())
+	}
+
 	l.mu.Lock()
 	defer l.mu.Unlock()
-	return l.plugins
+	if l.pluginsPB == nil {
+		l.pluginsPB = pluginsToPB(l.plugins.GetAll())
+	}
+	return l.pluginsPB
 }
 
 // Server returns the local server information

services/introspection/service.go

@@ -31,11 +31,8 @@ func init() {
 	plugin.Register(&plugin.Registration{
 		Type:     plugin.GRPCPlugin,
 		ID:       "introspection",
-		Requires: []plugin.Type{"*"},
+		Requires: []plugin.Type{plugin.ServicePlugin},
 		InitFn: func(ic *plugin.InitContext) (interface{}, error) {
-			// this service works by using the plugin context up till the point
-			// this service is initialized. Since we require this service last,
-			// it should provide the full set of plugins.
 			plugins, err := ic.GetByType(plugin.ServicePlugin)
 			if err != nil {
 				return nil, err
@@ -50,13 +47,11 @@ func init() {
 				return nil, err
 			}
 
-			allPluginsPB := pluginsToPB(ic.GetAll())
-
 			localClient, ok := i.(*Local)
 			if !ok {
 				return nil, errors.New("Could not create a local client for introspection service")
 			}
-			localClient.UpdateLocal(ic.Root, allPluginsPB)
+			localClient.UpdateLocal(ic.Root)
 
 			return &server{
 				local: localClient,