| /* |
| Copyright 2018 The Kubernetes Authors. |
| |
| Licensed under the Apache License, Version 2.0 (the "License"); |
| you may not use this file except in compliance with the License. |
| You may obtain a copy of the License at |
| |
| http://www.apache.org/licenses/LICENSE-2.0 |
| |
| Unless required by applicable law or agreed to in writing, software |
| distributed under the License is distributed on an "AS IS" BASIS, |
| WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| See the License for the specific language governing permissions and |
| limitations under the License. |
| */ |
| |
| package custom_metrics |
| |
| import ( |
| "sync" |
| "time" |
| |
| "k8s.io/apimachinery/pkg/api/meta" |
| "k8s.io/apimachinery/pkg/labels" |
| "k8s.io/apimachinery/pkg/runtime/schema" |
| "k8s.io/client-go/rest" |
| |
| "k8s.io/metrics/pkg/apis/custom_metrics/v1beta2" |
| ) |
| |
| // AvailableAPIsGetter knows how to fetch and cache the preferred custom metrics API version, |
| // and invalidate that cache when asked. |
| type AvailableAPIsGetter interface { |
| PreferredVersion() (schema.GroupVersion, error) |
| Invalidate() |
| } |
| |
| // PeriodicallyInvalidate periodically invalidates the preferred version cache until |
| // told to stop. |
| func PeriodicallyInvalidate(cache AvailableAPIsGetter, interval time.Duration, stopCh <-chan struct{}) { |
| ticker := time.NewTicker(interval) |
| defer ticker.Stop() |
| |
| for { |
| select { |
| case <-ticker.C: |
| cache.Invalidate() |
| case <-stopCh: |
| break |
| } |
| } |
| } |
| |
| // NewForConfig creates a new custom metrics client which delegates to a client which |
| // uses the preferred api version. |
| func NewForConfig(baseConfig *rest.Config, mapper meta.RESTMapper, availableAPIs AvailableAPIsGetter) CustomMetricsClient { |
| return &multiClient{ |
| clients: make(map[schema.GroupVersion]CustomMetricsClient), |
| availableAPIs: availableAPIs, |
| |
| newClient: func(ver schema.GroupVersion) (CustomMetricsClient, error) { |
| return NewForVersionForConfig(rest.CopyConfig(baseConfig), mapper, ver) |
| }, |
| } |
| } |
| |
| // multiClient is a CustomMetricsClient that can work with *any* metrics API version. |
| type multiClient struct { |
| newClient func(schema.GroupVersion) (CustomMetricsClient, error) |
| clients map[schema.GroupVersion]CustomMetricsClient |
| availableAPIs AvailableAPIsGetter |
| mu sync.RWMutex |
| } |
| |
| // getPreferredClient returns a custom metrics client of the preferred api version. |
| func (c *multiClient) getPreferredClient() (CustomMetricsClient, error) { |
| pref, err := c.availableAPIs.PreferredVersion() |
| if err != nil { |
| return nil, err |
| } |
| |
| c.mu.RLock() |
| client, present := c.clients[pref] |
| c.mu.RUnlock() |
| if present { |
| return client, nil |
| } |
| |
| c.mu.Lock() |
| defer c.mu.Unlock() |
| client, err = c.newClient(pref) |
| if err != nil { |
| return nil, err |
| } |
| c.clients[pref] = client |
| |
| return client, nil |
| } |
| |
| func (c *multiClient) RootScopedMetrics() MetricsInterface { |
| return &multiClientInterface{clients: c} |
| } |
| |
| func (c *multiClient) NamespacedMetrics(namespace string) MetricsInterface { |
| return &multiClientInterface{ |
| clients: c, |
| namespace: &namespace, |
| } |
| } |
| |
| type multiClientInterface struct { |
| clients *multiClient |
| namespace *string |
| } |
| |
| func (m *multiClientInterface) GetForObject(groupKind schema.GroupKind, name string, metricName string, metricSelector labels.Selector) (*v1beta2.MetricValue, error) { |
| client, err := m.clients.getPreferredClient() |
| if err != nil { |
| return nil, err |
| } |
| if m.namespace == nil { |
| return client.RootScopedMetrics().GetForObject(groupKind, name, metricName, metricSelector) |
| } else { |
| return client.NamespacedMetrics(*m.namespace).GetForObject(groupKind, name, metricName, metricSelector) |
| } |
| } |
| |
| func (m *multiClientInterface) GetForObjects(groupKind schema.GroupKind, selector labels.Selector, metricName string, metricSelector labels.Selector) (*v1beta2.MetricValueList, error) { |
| client, err := m.clients.getPreferredClient() |
| if err != nil { |
| return nil, err |
| } |
| if m.namespace == nil { |
| return client.RootScopedMetrics().GetForObjects(groupKind, selector, metricName, metricSelector) |
| } else { |
| return client.NamespacedMetrics(*m.namespace).GetForObjects(groupKind, selector, metricName, metricSelector) |
| } |
| } |