karmada/pkg/util/informermanager/multi-cluster-manager.go

115 lines
3.4 KiB
Go

package informermanager
import (
"sync"
"time"
"k8s.io/apimachinery/pkg/runtime/schema"
"k8s.io/client-go/dynamic"
)
var (
instance MultiClusterInformerManager
once sync.Once
)
// GetInstance returns a shared MultiClusterInformerManager instance.
func GetInstance() MultiClusterInformerManager {
once.Do(func() {
instance = NewMultiClusterInformerManager()
})
return instance
}
// MultiClusterInformerManager manages dynamic shared informer for all resources, include Kubernetes resource and
// custom resources defined by CustomResourceDefinition, across multi-cluster.
type MultiClusterInformerManager interface {
// ForCluster builds a informer manager for a specific cluster.
ForCluster(cluster string, client dynamic.Interface, defaultResync time.Duration) SingleClusterInformerManager
// GetSingleClusterManager gets the informer manager for a specific cluster.
// The informer manager should be created before, otherwise, nil will be returned.
GetSingleClusterManager(cluster string) SingleClusterInformerManager
// IsManagerExist checks if the informer manager for the cluster already created.
IsManagerExist(cluster string) bool
// Start will run all informers for a specific cluster, it accepts a stop channel, the informers will keep running until channel closed.
// Should call after 'ForCluster', otherwise no-ops.
Start(cluster string, stopCh <-chan struct{})
// WaitForCacheSync waits for all caches to populate.
// Should call after 'ForCluster', otherwise no-ops.
WaitForCacheSync(cluster string, stopCh <-chan struct{}) map[schema.GroupVersionResource]bool
}
// NewMultiClusterInformerManager constructs a new instance of multiClusterInformerManagerImpl.
func NewMultiClusterInformerManager() MultiClusterInformerManager {
return &multiClusterInformerManagerImpl{
managers: make(map[string]SingleClusterInformerManager),
}
}
type multiClusterInformerManagerImpl struct {
managers map[string]SingleClusterInformerManager
lock sync.RWMutex
}
func (m *multiClusterInformerManagerImpl) ForCluster(cluster string, client dynamic.Interface, defaultResync time.Duration) SingleClusterInformerManager {
// If informer manager already exist, just return
m.lock.RLock()
manager, exist := m.managers[cluster]
if exist {
m.lock.RUnlock()
return manager
}
m.lock.RUnlock()
m.lock.Lock()
defer m.lock.Unlock()
manager = NewSingleClusterInformerManager(client, defaultResync)
m.managers[cluster] = manager
return manager
}
func (m *multiClusterInformerManagerImpl) GetSingleClusterManager(cluster string) SingleClusterInformerManager {
m.lock.RLock()
defer m.lock.RUnlock()
manager, exist := m.managers[cluster]
if exist {
return manager
}
return nil
}
func (m *multiClusterInformerManagerImpl) IsManagerExist(cluster string) bool {
m.lock.RLock()
defer m.lock.RUnlock()
_, exist := m.managers[cluster]
return exist
}
func (m *multiClusterInformerManagerImpl) Start(cluster string, stopCh <-chan struct{}) {
m.lock.RLock()
defer m.lock.RUnlock()
// if informer manager haven't been created, just return with no-ops.
manager, exist := m.managers[cluster]
if !exist {
return
}
manager.Start(stopCh)
}
func (m *multiClusterInformerManagerImpl) WaitForCacheSync(cluster string, stopCh <-chan struct{}) map[schema.GroupVersionResource]bool {
m.lock.RLock()
defer m.lock.RUnlock()
manager, exist := m.managers[cluster]
if !exist {
return nil
}
return manager.WaitForCacheSync(stopCh)
}