text: /*
  Copyright 2019 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 metrics
  
  import (
  	"sync"
  
  	"k8s.io/component-base/metrics"
  	"k8s.io/component-base/metrics/legacyregistry"
  	"k8s.io/kubernetes/pkg/kubelet/pluginmanager/cache"
  )
  
  const (
  	// Metric keys for Plugin Manager.
  	pluginManagerTotalPlugins = "plugin_manager_total_plugins"
  )
  
  var (
  	registerMetrics sync.Once
  
  	totalPluginsDesc = metrics.NewDesc(
  		pluginManagerTotalPlugins,
  		"Number of plugins in Plugin Manager",
  		[]string{"socket_path", "state"},
  		nil,
  		metrics.ALPHA,
  		"",
  	)
  )
  
  // pluginCount is a map of maps used as a counter.
  type pluginCount map[string]map[string]int64
  
  func (pc pluginCount) add(state, pluginName string) {
  	count, ok := pc[state]
  	if !ok {
  		count = map[string]int64{}
  	}
  	count[pluginName]++
  	pc[state] = count
  }
  
  // Register registers Plugin Manager metrics.
  func Register(asw cache.ActualStateOfWorld, dsw cache.DesiredStateOfWorld) {
  	registerMetrics.Do(func() {
  		legacyregistry.CustomMustRegister(&totalPluginsCollector{asw: asw, dsw: dsw})
  	})
  }
  
  type totalPluginsCollector struct {
  	metrics.BaseStableCollector
  
  	asw cache.ActualStateOfWorld
  	dsw cache.DesiredStateOfWorld
  }
  
  var _ metrics.StableCollector = &totalPluginsCollector{}
  
  // DescribeWithStability implements the metrics.StableCollector interface.
  func (c *totalPluginsCollector) DescribeWithStability(ch chan<- *metrics.Desc) {
  	ch <- totalPluginsDesc
  }
  
  // CollectWithStability implements the metrics.StableCollector interface.
  func (c *totalPluginsCollector) CollectWithStability(ch chan<- metrics.Metric) {
  	for stateName, pluginCount := range c.getPluginCount() {
  		for socketPath, count := range pluginCount {
  			ch <- metrics.NewLazyConstMetric(totalPluginsDesc,
  				metrics.GaugeValue,
  				float64(count),
  				socketPath,
  				stateName)
  		}
  	}
  }
  
  func (c *totalPluginsCollector) getPluginCount() pluginCount {
  	counter := make(pluginCount)
  	for _, registeredPlugin := range c.asw.GetRegisteredPlugins() {
  		socketPath := registeredPlugin.SocketPath
  		counter.add("actual_state_of_world", socketPath)
  	}
  
  	for _, pluginToRegister := range c.dsw.GetPluginsToRegister() {
  		socketPath := pluginToRegister.SocketPath
  		counter.add("desired_state_of_world", socketPath)
  	}
  	return counter
  }
  