chore: notify dependent components when a component updated

controllers/apps/component/component_controller.go

@@ -174,6 +174,8 @@ func (r *ComponentReconciler) Reconcile(ctx context.Context, req ctrl.Request) (
 			&componentPostProvisionTransformer{},
 			// update component status
 			&componentStatusTransformer{Client: r.Client},
+			// notify dependent components the possible spec changes
+			&componentNotifierTransformer{},
 		).Build()
 
 	// Execute stage

controllers/apps/component/transformer_component_deletion.go

@@ -23,8 +23,10 @@ import (
 	"fmt"
 	"time"
 
+	"github.com/pkg/errors"
 	corev1 "k8s.io/api/core/v1"
 	rbacv1 "k8s.io/api/rbac/v1"
+	"k8s.io/apimachinery/pkg/types"
 	"k8s.io/klog/v2"
 	"sigs.k8s.io/controller-runtime/pkg/client"
 	"sigs.k8s.io/controller-runtime/pkg/client/apiutil"
@@ -140,6 +142,9 @@ func (t *componentDeletionTransformer) deleteCompResources(transCtx *componentTr
 		graphCli.Status(dag, comp, transCtx.Component)
 		return intctrlutil.NewRequeueError(time.Second*1, "not all component sub-resources deleted")
 	} else {
+		if err = notifyDependents4CompDeletion(transCtx, dag); err != nil {
+			return intctrlutil.NewRequeueError(appsutil.RequeueDuration, fmt.Sprintf("notify dependent components error: %s", err.Error()))
+		}
 		graphCli.Delete(dag, comp)
 	}
 
@@ -211,6 +216,33 @@ func handleRBACResourceDeletion(obj client.Object, transCtx *componentTransformC
 	}
 }
 
+func notifyDependents4CompDeletion(transCtx *componentTransformContext, dag *graph.DAG) error {
+	var (
+		ctx  = transCtx.Context
+		cli  = transCtx.Client
+		comp = transCtx.Component
+	)
+
+	compDef := &appsv1.ComponentDefinition{}
+	if err := transCtx.Client.Get(transCtx.Context, types.NamespacedName{Name: comp.Spec.CompDef}, compDef); err != nil {
+		return errors.Wrap(err, "failed to get the component definition for dependents notifier at deletion")
+	}
+
+	synthesizedComp, err := component.BuildSynthesizedComponent(ctx, cli, compDef, comp)
+	if err != nil {
+		return errors.Wrap(err, "failed to build synthesized component for dependents notifier at deletion")
+	}
+
+	bak := transCtx.SynthesizeComponent
+	defer func() {
+		transCtx.SynthesizeComponent = bak
+	}()
+
+	transCtx.SynthesizeComponent = synthesizedComp
+	transformer := &componentNotifierTransformer{}
+	return transformer.Transform(transCtx, dag)
+}
+
 func compOwnedWorkloadKinds() []client.ObjectList {
 	return []client.ObjectList{
 		&workloads.InstanceSetList{},

controllers/apps/component/transformer_component_notifier.go

@@ -0,0 +1,143 @@
+/*
+Copyright (C) 2022-2025 ApeCloud Co., Ltd
+
+This file is part of KubeBlocks project
+
+This program is free software: you can redistribute it and/or modify
+it under the terms of the GNU Affero General Public License as published by
+the Free Software Foundation, either version 3 of the License, or
+(at your option) any later version.
+
+This program is distributed in the hope that it will be useful
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+GNU Affero General Public License for more details.
+
+You should have received a copy of the GNU Affero General Public License
+along with this program.  If not, see <http://www.gnu.org/licenses/>.
+*/
+
+package component
+
+import (
+	"fmt"
+	"time"
+
+	"k8s.io/apimachinery/pkg/types"
+	"sigs.k8s.io/controller-runtime/pkg/client"
+
+	appsv1 "github.com/apecloud/kubeblocks/apis/apps/v1"
+	"github.com/apecloud/kubeblocks/pkg/constant"
+	"github.com/apecloud/kubeblocks/pkg/controller/component"
+	"github.com/apecloud/kubeblocks/pkg/controller/graph"
+	"github.com/apecloud/kubeblocks/pkg/controller/model"
+)
+
+type componentNotifierTransformer struct{}
+
+var _ graph.Transformer = &componentNotifierTransformer{}
+
+func (t *componentNotifierTransformer) Transform(ctx graph.TransformContext, dag *graph.DAG) error {
+	transCtx, _ := ctx.(*componentTransformContext)
+	if !model.IsObjectUpdating(transCtx.ComponentOrig) {
+		return nil
+	}
+
+	dependents, err := t.dependents(transCtx)
+	if err != nil {
+		return err
+	}
+
+	graphCli, _ := transCtx.Client.(model.GraphClient)
+	for _, compName := range dependents {
+		if err = t.notify(transCtx, graphCli, dag, compName); err != nil {
+			return err
+		}
+	}
+	return nil
+}
+
+func (t *componentNotifierTransformer) dependents(transCtx *componentTransformContext) ([]string, error) {
+	synthesizedComp := transCtx.SynthesizeComponent
+	dependents := make([]string, 0)
+	for compName, compDefName := range synthesizedComp.Comp2CompDefs {
+		if compName == synthesizedComp.Name {
+			continue // skip self
+		}
+		depended, err := t.depended(transCtx, compDefName)
+		if err != nil {
+			return nil, err
+		}
+		if depended {
+			dependents = append(dependents, compName)
+		}
+	}
+	return dependents, nil
+}
+
+func (t *componentNotifierTransformer) depended(transCtx *componentTransformContext, compDefName string) (bool, error) {
+	compDefReferenced := func(v appsv1.EnvVar) string {
+		if v.ValueFrom != nil {
+			if v.ValueFrom.HostNetworkVarRef != nil {
+				return v.ValueFrom.HostNetworkVarRef.CompDef
+			}
+			if v.ValueFrom.ServiceVarRef != nil {
+				return v.ValueFrom.ServiceVarRef.CompDef
+			}
+			if v.ValueFrom.CredentialVarRef != nil {
+				return v.ValueFrom.CredentialVarRef.CompDef
+			}
+			if v.ValueFrom.TLSVarRef != nil {
+				return v.ValueFrom.TLSVarRef.CompDef
+			}
+			if v.ValueFrom.ServiceRefVarRef != nil {
+				return v.ValueFrom.ServiceRefVarRef.CompDef
+			}
+			if v.ValueFrom.ComponentVarRef != nil {
+				return v.ValueFrom.ComponentVarRef.CompDef
+			}
+		}
+		return ""
+	}
+
+	compDef, err := getNCheckCompDefinition(transCtx.Context, transCtx.Client, compDefName)
+	if err != nil {
+		return false, err
+	}
+
+	synthesizedComp := transCtx.SynthesizeComponent
+	for _, v := range compDef.Spec.Vars {
+		compDefPattern := compDefReferenced(v)
+		if len(compDefPattern) > 0 {
+			if component.PrefixOrRegexMatched(synthesizedComp.CompDefName, compDefPattern) {
+				return true, nil
+			}
+		}
+	}
+	return false, nil
+}
+
+func (t *componentNotifierTransformer) notify(transCtx *componentTransformContext,
+	graphCli model.GraphClient, dag *graph.DAG, compName string) error {
+	synthesizedComp := transCtx.SynthesizeComponent
+
+	comp := &appsv1.Component{}
+	compKey := types.NamespacedName{
+		Namespace: synthesizedComp.Namespace,
+		Name:      constant.GenerateClusterComponentName(synthesizedComp.ClusterName, compName),
+	}
+	if err := transCtx.Client.Get(transCtx.Context, compKey, comp); err != nil {
+		return client.IgnoreNotFound(err)
+	}
+
+	compCopy := comp.DeepCopy()
+	if compCopy.Annotations == nil {
+		compCopy.Annotations = make(map[string]string)
+	}
+	compCopy.Annotations[constant.ReconcileAnnotationKey] =
+		fmt.Sprintf("%s@%s", synthesizedComp.Name, time.Now().Format(time.RFC3339))
+
+	graphCli.Patch(dag, comp, compCopy)
+
+	return nil
+}