优化结构

internal/integration/mq/emqx.go

@@ -402,7 +402,7 @@ func (r *Reloadable) clientLocked(provider string) platformmq.Client {
 	return r.clients[provider]
 }
 
-func (r *Reloadable) reconcileProviderLocked(provider string) error {
+func (r *Reloadable) reconcileProviderLocked(provider string) (err error) {
 	client := r.clientLocked(provider)
 	desired := r.desiredSubscriptions(provider)
 	if client == nil || !client.Connected() {
@@ -419,6 +419,10 @@ func (r *Reloadable) reconcileProviderLocked(provider string) error {
 		current[topic] = qos
 	}
 	r.mu.RUnlock()
+	// Broker operations can partially succeed. Persist every successful
+	// change even when a later operation fails, otherwise the next retry will
+	// repeat stale unbinds and may never reach the remaining subscriptions.
+	defer func() { r.setBindings(provider, current) }()
 	for topic := range current {
 		if _, exists := desired[topic]; exists {
 			continue
@@ -436,20 +440,31 @@ func (r *Reloadable) reconcileProviderLocked(provider string) error {
 			if err := client.Unsubscribe(context.Background(), topic); err != nil {
 				return err
 			}
+			delete(current, topic)
 		}
 		if err := client.Subscribe(context.Background(), topic, qos, r.dispatcher(provider, topic)); err != nil {
 			return err
 		}
 		current[topic] = qos
 	}
-	r.mu.Lock()
-	r.bindings[provider] = current
-	r.mu.Unlock()
 	delete(r.pending, provider)
 	delete(r.nextRetry, provider)
 	return nil
 }
 
+func (r *Reloadable) setBindings(provider string, bindings map[string]byte) {
+	copyOfBindings := make(map[string]byte, len(bindings))
+	for topic, qos := range bindings {
+		copyOfBindings[topic] = qos
+	}
+	r.mu.Lock()
+	if r.bindings == nil {
+		r.bindings = make(map[string]map[string]byte)
+	}
+	r.bindings[provider] = copyOfBindings
+	r.mu.Unlock()
+}
+
 func (r *Reloadable) Register(set platformmq.SubscriptionSet) error {
 	normalized, err := platformmq.NormalizeSubscriptionSet(set)
 	if err != nil {
@@ -526,6 +541,9 @@ func (r *Reloadable) Publish(ctx context.Context, topic string, payload []byte,
 }
 
 func (r *Reloadable) PublishTo(ctx context.Context, provider, topic string, payload []byte, qos byte, retain bool) error {
+	if ctx == nil {
+		ctx = context.Background()
+	}
 	provider = strings.ToLower(strings.TrimSpace(provider))
 	client := r.clientLocked(provider)
 	if client == nil {
@@ -539,6 +557,9 @@ func (r *Reloadable) Subscribe(ctx context.Context, topic string, qos byte, hand
 }
 
 func (r *Reloadable) SubscribeTo(ctx context.Context, provider, topic string, qos byte, handler platformmq.Handler) error {
+	if ctx == nil {
+		ctx = context.Background()
+	}
 	if ctx != nil {
 		select {
 		case <-ctx.Done():
@@ -555,6 +576,9 @@ func (r *Reloadable) SubscribeTo(ctx context.Context, provider, topic string, qo
 		return err
 	}
 	if !r.ConnectedTo(provider) {
+		// The legacy API reports unavailable when no live broker exists. Do not
+		// leave a durable declaration behind when that call failed.
+		_ = r.Unregister(owner)
 		return platformmq.ErrUnavailable
 	}
 	return nil
@@ -565,6 +589,9 @@ func (r *Reloadable) Unsubscribe(ctx context.Context, topics ...string) error {
 }
 
 func (r *Reloadable) UnsubscribeFrom(ctx context.Context, provider string, topics ...string) error {
+	if ctx == nil {
+		ctx = context.Background()
+	}
 	if ctx != nil {
 		select {
 		case <-ctx.Done():
@@ -660,22 +687,24 @@ func (r *Reloadable) Close() error {
 }
 
 func (r *Reloadable) ensureStateLocked() {
-	if r.clients == nil {
-		r.clients = make(map[string]platformmq.Client)
-	}
 	if r.configs == nil {
 		r.configs = make(map[string]runtimeconfig.Config)
 	}
-	if r.subscriptions == nil {
-		r.subscriptions = make(map[string]map[string]map[string]subscription)
-	}
-	if r.bindings == nil {
-		r.bindings = make(map[string]map[string]byte)
-	}
 	if r.pending == nil {
 		r.pending = make(map[string]bool)
 	}
 	if r.nextRetry == nil {
 		r.nextRetry = make(map[string]time.Time)
 	}
+	r.mu.Lock()
+	if r.clients == nil {
+		r.clients = make(map[string]platformmq.Client)
+	}
+	if r.subscriptions == nil {
+		r.subscriptions = make(map[string]map[string]map[string]subscription)
+	}
+	if r.bindings == nil {
+		r.bindings = make(map[string]map[string]byte)
+	}
+	r.mu.Unlock()
 }