Adding config extension to CCM.

cmd/cloud-controller-manager/controller-manager.go

@@ -17,32 +17,130 @@ limitations under the License.
 // The external controller manager is responsible for running controller loops that
 // are cloud provider dependent. It uses the API to listen to new events on resources.
 
+// This file should be written by each cloud provider.
+// The current file demonstrate how other cloud provider should leverage CCM and it uses fake parameters. Please modify for your own use.
+
 package main
 
 import (
+	"fmt"
 	"math/rand"
+	"net/http"
 	"os"
 	"time"
 
+	"github.com/spf13/pflag"
+	cloudprovider "k8s.io/cloud-provider"
 	"k8s.io/cloud-provider/app"
+	cloudcontrollerconfig "k8s.io/cloud-provider/app/config"
+	"k8s.io/cloud-provider/options"
+	"k8s.io/component-base/cli/flag"
 	"k8s.io/component-base/logs"
 	_ "k8s.io/component-base/metrics/prometheus/clientgo" // load all the prometheus client-go plugins
 	_ "k8s.io/component-base/metrics/prometheus/version"  // for version metric registration
+	genericcontrollermanager "k8s.io/controller-manager/app"
+	"k8s.io/klog/v2"
+	nodeipamconfig "k8s.io/kubernetes/pkg/controller/nodeipam/config"
+)
+
+const (
+	// cloudProviderName shows an sample of using hard coded parameter
+	cloudProviderName = "SampleCloudProviderName"
+
+	// defaultNodeMaskCIDRIPv4 is default mask size for IPv4 node cidr
+	defaultNodeMaskCIDRIPv4 = 24
+	// defaultNodeMaskCIDRIPv6 is default mask size for IPv6 node cidr
+	defaultNodeMaskCIDRIPv6 = 64
 )
 
 func main() {
 	rand.Seed(time.Now().UnixNano())
 
-	command := app.NewCloudControllerManagerCommand()
+	// cloudProviderConfigFile shows an sample of parse config file from flag option
+	var flagset *pflag.FlagSet = pflag.NewFlagSet("flagSet", pflag.ContinueOnError)
+	var cloudProviderConfigFile *string = flagset.String("cloud-provider-configfile", "", "This is the sample input for cloud provider config file")
+	pflag.CommandLine.ParseErrorsWhitelist.UnknownFlags = true
+	_ = pflag.CommandLine.Parse(os.Args[1:])
+
+	// this is an example of allow-listing specific controller loops
+	controllerList := []string{"cloud-node", "cloud-node-lifecycle", "service", "route"}
+
+	s, err := options.NewCloudControllerManagerOptions()
+	if err != nil {
+		klog.Fatalf("unable to initialize command options: %v", err)
+	}
+	c, err := s.Config(controllerList, app.ControllersDisabledByDefault.List())
+	if err != nil {
+		fmt.Fprintf(os.Stderr, "%v\n", err)
+		os.Exit(1)
+	}
+
+	cloud, err := cloudprovider.InitCloudProvider(cloudProviderName, *cloudProviderConfigFile)
+	if err != nil {
+		klog.Fatalf("Cloud provider could not be initialized: %v", err)
+	}
+	if cloud == nil {
+		klog.Fatalf("cloud provider is nil")
+	}
+
+	if !cloud.HasClusterID() {
+		if c.ComponentConfig.KubeCloudShared.AllowUntaggedCloud {
+			klog.Warning("detected a cluster without a ClusterID.  A ClusterID will be required in the future.  Please tag your cluster to avoid any future issues")
+		} else {
+			klog.Fatalf("no ClusterID found.  A ClusterID is required for the cloud provider to function properly.  This check can be bypassed by setting the allow-untagged-cloud option")
+		}
+	}
+
+	// Initialize the cloud provider with a reference to the clientBuilder
+	cloud.Initialize(c.ClientBuilder, make(chan struct{}))
+	// Set the informer on the user cloud object
+	if informerUserCloud, ok := cloud.(cloudprovider.InformerUser); ok {
+		informerUserCloud.SetInformers(c.SharedInformers)
+	}
+
+	controllerInitializers := app.DefaultControllerInitializers(c.Complete(), cloud)
+
+	// Here is an example to remove the controller which is not needed.
+	// e.g. remove the cloud-node-lifecycle controller which current cloud provider does not need.
+	//delete(controllerInitializers, "cloud-node-lifecycle")
+
+	// Here is an example to add an controller(NodeIpamController) which will be used by cloud provider
+	// generate nodeipamconfig. Here is an sample code. Please pass the right parameter in your code.
+	// If you do not need additional controller, please ignore.
+	nodeipamconfig := nodeipamconfig.NodeIPAMControllerConfiguration{
+		ServiceCIDR:          "sample",
+		SecondaryServiceCIDR: "sample",
+		NodeCIDRMaskSize:     11,
+		NodeCIDRMaskSizeIPv4: 11,
+		NodeCIDRMaskSizeIPv6: 111,
+	}
+	controllerInitializers["nodeipam"] = startNodeIpamControllerWrapper(c.Complete(), nodeipamconfig, cloud)
+
+	command := app.NewCloudControllerManagerCommand(s, c, controllerInitializers)
 
 	// TODO: once we switch everything over to Cobra commands, we can go back to calling
 	// utilflag.InitFlags() (by removing its pflag.Parse() call). For now, we have to set the
 	// normalize func and add the go flag set by hand.
+	// Here is an sample
+	pflag.CommandLine.SetNormalizeFunc(flag.WordSepNormalizeFunc)
 	// utilflag.InitFlags()
 	logs.InitLogs()
 	defer logs.FlushLogs()
 
+	// the flags could be set before execute
+	command.Flags().VisitAll(func(flag *pflag.Flag) {
+		if flag.Name == "cloud-provider" {
+			flag.Value.Set("SampleCloudProviderFlagValue")
+			return
+		}
+	})
 	if err := command.Execute(); err != nil {
 		os.Exit(1)
 	}
 }
+
+func startNodeIpamControllerWrapper(ccmconfig *cloudcontrollerconfig.CompletedConfig, nodeipamconfig nodeipamconfig.NodeIPAMControllerConfiguration, cloud cloudprovider.Interface) func(ctx genericcontrollermanager.ControllerContext) (http.Handler, bool, error) {
+	return func(ctx genericcontrollermanager.ControllerContext) (http.Handler, bool, error) {
+		return startNodeIpamController(ccmconfig, nodeipamconfig, ctx, cloud)
+	}
+}