feat(os/gcfg): add Loader with automatic struct binding and config watching (like Spring Boot @ConfigurationProperties)

contrib/config/apollo/apollo.go

@@ -179,7 +179,7 @@ func (c *Client) updateLocalValue(ctx context.Context) (err error) {
 }
 
 // AddWatcher adds a watcher for the specified configuration file.
-func (c *Client) AddWatcher(name string, f func(ctx context.Context)) {
+func (c *Client) AddWatcher(name string, f gcfg.WatcherFunc) {
 	c.watchers.Add(name, f)
 }
 
@@ -193,6 +193,11 @@ func (c *Client) GetWatcherNames() []string {
 	return c.watchers.GetNames()
 }
 
+// IsWatching checks whether the watcher with the specified name is registered.
+func (c *Client) IsWatching(name string) bool {
+	return c.watchers.IsWatching(name)
+}
+
 // notifyWatchers notifies all watchers.
 func (c *Client) notifyWatchers(ctx context.Context) {
 	c.watchers.Notify(ctx)

contrib/config/consul/consul.go

@@ -207,7 +207,7 @@ func (c *Client) startAsynchronousWatch(plan *watch.Plan) {
 }
 
 // AddWatcher adds a watcher for the specified configuration file.
-func (c *Client) AddWatcher(name string, f func(ctx context.Context)) {
+func (c *Client) AddWatcher(name string, f gcfg.WatcherFunc) {
 	c.watchers.Add(name, f)
 }
 
@@ -221,6 +221,11 @@ func (c *Client) GetWatcherNames() []string {
 	return c.watchers.GetNames()
 }
 
+// IsWatching checks whether the watcher with the specified name is registered.
+func (c *Client) IsWatching(name string) bool {
+	return c.watchers.IsWatching(name)
+}
+
 // notifyWatchers notifies all watchers.
 func (c *Client) notifyWatchers(ctx context.Context) {
 	c.watchers.Notify(ctx)

contrib/config/kubecm/kubecm.go

@@ -199,7 +199,7 @@ func (c *Client) startAsynchronousWatch(ctx context.Context, namespace string, w
 }
 
 // AddWatcher adds a watcher for the specified configuration file.
-func (c *Client) AddWatcher(name string, f func(ctx context.Context)) {
+func (c *Client) AddWatcher(name string, f gcfg.WatcherFunc) {
 	c.watchers.Add(name, f)
 }
 
@@ -213,6 +213,11 @@ func (c *Client) GetWatcherNames() []string {
 	return c.watchers.GetNames()
 }
 
+// IsWatching checks whether the watcher with the specified name is registered.
+func (c *Client) IsWatching(name string) bool {
+	return c.watchers.IsWatching(name)
+}
+
 // notifyWatchers notifies all watchers.
 func (c *Client) notifyWatchers(ctx context.Context) {
 	c.watchers.Notify(ctx)

contrib/config/nacos/nacos.go

@@ -152,7 +152,7 @@ func (c *Client) addWatcher() error {
 }
 
 // AddWatcher adds a watcher for the specified configuration file.
-func (c *Client) AddWatcher(name string, f func(ctx context.Context)) {
+func (c *Client) AddWatcher(name string, f gcfg.WatcherFunc) {
 	c.watchers.Add(name, f)
 }
 
@@ -166,6 +166,11 @@ func (c *Client) GetWatcherNames() []string {
 	return c.watchers.GetNames()
 }
 
+// IsWatching checks whether the watcher with the specified name is registered.
+func (c *Client) IsWatching(name string) bool {
+	return c.watchers.IsWatching(name)
+}
+
 // notifyWatchers notifies all watchers.
 func (c *Client) notifyWatchers(ctx context.Context) {
 	c.watchers.Notify(ctx)

contrib/config/polaris/polaris.go

@@ -187,7 +187,7 @@ func (c *Client) startAsynchronousWatch(ctx context.Context, changeChan <-chan m
 }
 
 // AddWatcher adds a watcher for the specified configuration file.
-func (c *Client) AddWatcher(name string, f func(ctx context.Context)) {
+func (c *Client) AddWatcher(name string, f gcfg.WatcherFunc) {
 	c.watchers.Add(name, f)
 }
 
@@ -201,6 +201,11 @@ func (c *Client) GetWatcherNames() []string {
 	return c.watchers.GetNames()
 }
 
+// IsWatching checks whether the watcher with the specified name is registered.
+func (c *Client) IsWatching(name string) bool {
+	return c.watchers.IsWatching(name)
+}
+
 // notifyWatchers notifies all watchers.
 func (c *Client) notifyWatchers(ctx context.Context) {
 	c.watchers.Notify(ctx)

os/gcfg/gcfg_adaper.go

@@ -29,12 +29,17 @@ type Adapter interface {
 	Data(ctx context.Context) (data map[string]any, err error)
 }
 
+// WatcherFunc is the callback function type for configuration watchers.
+type WatcherFunc = func(context.Context)
+
 // WatcherAdapter is the interface for configuration watcher.
 type WatcherAdapter interface {
 	// AddWatcher adds a watcher function for specified `pattern` and `resource`.
-	AddWatcher(name string, fn func(ctx context.Context))
+	AddWatcher(name string, fn WatcherFunc)
 	// RemoveWatcher removes the watcher function for specified `pattern` and `resource`.
 	RemoveWatcher(name string)
 	// GetWatcherNames returns all watcher names.
 	GetWatcherNames() []string
+	// IsWatching checks and returns whether the specified `pattern` is watching.
+	IsWatching(name string) bool
 }

os/gcfg/gcfg_adapter_content.go

@@ -86,7 +86,7 @@ func (a *AdapterContent) Data(ctx context.Context) (data map[string]any, err err
 }
 
 // AddWatcher adds a watcher for the specified configuration file.
-func (a *AdapterContent) AddWatcher(name string, fn func(ctx context.Context)) {
+func (a *AdapterContent) AddWatcher(name string, fn WatcherFunc) {
 	a.watchers.Add(name, fn)
 }
 
@@ -100,6 +100,11 @@ func (a *AdapterContent) GetWatcherNames() []string {
 	return a.watchers.GetNames()
 }
 
+// IsWatching checks and returns whether the specified `name` is watching.
+func (a *AdapterContent) IsWatching(name string) bool {
+	return a.watchers.IsWatching(name)
+}
+
 // notifyWatchers notifies all watchers.
 func (a *AdapterContent) notifyWatchers(ctx context.Context) {
 	a.watchers.Notify(ctx)

os/gcfg/gcfg_adapter_file.go

@@ -332,7 +332,7 @@ func (a *AdapterFile) getJson(fileNameOrPath ...string) (configJson *gjson.Json,
 }
 
 // AddWatcher adds a watcher for the specified configuration file.
-func (a *AdapterFile) AddWatcher(name string, fn func(ctx context.Context)) {
+func (a *AdapterFile) AddWatcher(name string, fn WatcherFunc) {
 	a.watchers.Add(name, fn)
 }
 
@@ -346,6 +346,11 @@ func (a *AdapterFile) GetWatcherNames() []string {
 	return a.watchers.GetNames()
 }
 
+// IsWatching checks and returns whether the specified `name` is watching.
+func (a *AdapterFile) IsWatching(name string) bool {
+	return a.watchers.IsWatching(name)
+}
+
 // notifyWatchers notifies all watchers.
 func (a *AdapterFile) notifyWatchers(ctx context.Context) {
 	a.watchers.Notify(ctx)