repo_description: Kubernetes Operations (kOps) - Production Grade k8s Installation, Upgrades and Management
repo_topics: cncf containers go kops kubernetes
code: /*
  Copyright 2020 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 main
  
  import (
  	"context"
  	"encoding/json"
  	"fmt"
  	"io"
  	"strings"
  
  	"k8s.io/client-go/kubernetes"
  	"k8s.io/kops/pkg/cloudinstances"
  	"k8s.io/kops/pkg/commands/commandutils"
  	"k8s.io/kops/pkg/kubeconfig"
  	"k8s.io/kubectl/pkg/util/i18n"
  	"k8s.io/kubectl/pkg/util/templates"
  	"sigs.k8s.io/yaml"
  
  	"k8s.io/klog/v2"
  
  	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
  
  	"k8s.io/kops/util/pkg/tables"
  
  	"k8s.io/kops/pkg/apis/kops"
  
  	"github.com/spf13/cobra"
  	"k8s.io/kops/cmd/kops/util"
  	"k8s.io/kops/upup/pkg/fi/cloudup"
  )
  
  var (
  	getInstancesExample = templates.Examples(i18n.T(`
  	# Display all instances.
  	kops get instances
  	`))
  
  	getInstancesShort = i18n.T(`Display cluster instances.`)
  )
  
  type renderableCloudInstance struct {
  	ID            string   `json:"id"`
  	NodeName      string   `json:"nodeName,omitempty"`
  	Status        string   `json:"status"`
  	Roles         []string `json:"roles"`
  	InternalIP    string   `json:"internalIP"`
  	ExternalIP    string   `json:"externalIP"`
  	InstanceGroup string   `json:"instanceGroup"`
  	MachineType   string   `json:"machineType"`
  	State         string   `json:"state"`
  }
  
  type GetInstancesOptions struct {
  	*GetOptions
  	kubeconfig.CreateKubecfgOptions
  }
  
  func NewCmdGetInstances(f *util.Factory, out io.Writer, options *GetOptions) *cobra.Command {
  	opt := GetInstancesOptions{
  		GetOptions: options,
  	}
  	cmd := &cobra.Command{
  		Use:               "instances [CLUSTER]",
  		Short:             getInstancesShort,
  		Example:           getInstancesExample,
  		Args:              rootCommand.clusterNameArgs(&options.ClusterName),
  		ValidArgsFunction: commandutils.CompleteClusterName(f, true, false),
  		RunE: func(cmd *cobra.Command, args []string) error {
  			return RunGetInstances(cmd.Context(), f, out, &opt)
  		},
  	}
  
  	opt.CreateKubecfgOptions.AddCommonFlags(cmd.Flags())
  
  	return cmd
  }
  
  func RunGetInstances(ctx context.Context, f *util.Factory, out io.Writer, options *GetInstancesOptions) error {
  	clientset, err := f.KopsClient()
  	if err != nil {
  		return err
  	}
  
  	cluster, err := clientset.GetCluster(ctx, options.ClusterName)
  	if err != nil {
  		return err
  	}
  
  	if cluster == nil {
  		return fmt.Errorf("cluster not found %q", options.ClusterName)
  	}
  
  	cloud, err := cloudup.BuildCloud(cluster)
  	if err != nil {
  		return err
  	}
  
  	restConfig, err := f.RESTConfig(ctx, cluster, options.CreateKubecfgOptions)
  	if err != nil {
  		return err
  	}
  
  	httpClient, err := f.HTTPClient(restConfig)
  	if err != nil {
  		return err
  	}
  
  	k8sClient, err := kubernetes.NewForConfigAndClient(restConfig, httpClient)
  	if err != nil {
  		return fmt.Errorf("building kubernetes client: %w", err)
  	}
  
  	nodeList, err := k8sClient.CoreV1().Nodes().List(ctx, metav1.ListOptions{})
  	if err != nil {
  		klog.Warningf("cannot list node names. Kubernetes API unavailable: %v", err)
  	}
  
  	igList, err := clientset.InstanceGroupsFor(cluster).List(ctx, metav1.ListOptions{})
  	if err != nil {
  		return err
  	}
  
  	var instanceGroups []*kops.InstanceGroup
  	for i := range igList.Items {
  		instanceGroups = append(instanceGroups, &igList.Items[i])
  	}
  
  	var cloudInstances []*cloudinstances.CloudInstance
  
  	cloudGroups, err := cloud.GetCloudGroups(cluster, instanceGroups, false, nodeList.Items)
  	if err != nil {
  		return err
  	}
  
  	for _, cg := range cloudGroups {
  		cloudInstances = append(cloudInstances, cg.Ready...)
  		cloudInstances = append(cloudInstances, cg.NeedUpdate...)
  		cg.AdjustNeedUpdate()
  	}
  
  	switch options.Output {
  	case OutputTable:
  		return instanceOutputTable(cloudInstances, out)
  	case OutputYaml:
  		y, err := yaml.Marshal(asRenderable(cloudInstances))
  		if err != nil {
  			return fmt.Errorf("unable to marshal YAML: %v", err)
  		}
  		if _, err := out.Write(y); err != nil {
  			return fmt.Errorf("error writing to output: %v", err)
  		}
  		return nil
  	case OutputJSON:
  		j, err := json.Marshal(asRenderable(cloudInstances))
  		if err != nil {
  			return fmt.Errorf("unable to marshal JSON: %v", err)
  		}
  		if _, err := out.Write(j); err != nil {
  			return fmt.Errorf("error writing to output: %v", err)
  		}
  		return nil
  	default:
  		return fmt.Errorf("unsupported output format: %q", options.Output)
  	}
  }
  
  func instanceOutputTable(instances []*cloudinstances.CloudInstance, out io.Writer) error {
  	fmt.Println("")
  	t := &tables.Table{}
  	t.AddColumn("ID", func(i *cloudinstances.CloudInstance) string {
  		return i.ID
  	})
  	t.AddColumn("NODE-NAME", func(i *cloudinstances.CloudInstance) string {
  		node := i.Node
  		if node == nil {
  			return ""
  		} else {
  			return node.Name
  		}
  	})
  	t.AddColumn("STATUS", func(i *cloudinstances.CloudInstance) string {
  		return i.Status
  	})
  	t.AddColumn("ROLES", func(i *cloudinstances.CloudInstance) string {
  		return strings.Join(i.Roles, ", ")
  	})
  	t.AddColumn("INTERNAL-IP", func(i *cloudinstances.CloudInstance) string {
  		return i.PrivateIP
  	})
  	t.AddColumn("EXTERNAL-IP", func(i *cloudinstances.CloudInstance) string {
  		return i.ExternalIP
  	})
  	t.AddColumn("INSTANCE-GROUP", func(i *cloudinstances.CloudInstance) string {
  		return i.CloudInstanceGroup.HumanName
  	})
  	t.AddColumn("MACHINE-TYPE", func(i *cloudinstances.CloudInstance) string {
  		return i.MachineType
  	})
  	t.AddColumn("STATE", func(i *cloudinstances.CloudInstance) string {
  		return string(i.State)
  	})
  
  	columns := []string{"ID", "NODE-NAME", "STATUS", "ROLES", "STATE", "INTERNAL-IP", "EXTERNAL-IP", "INSTANCE-GROUP", "MACHINE-TYPE"}
  	return t.Render(instances, out, columns...)
  }
  
  func asRenderable(instances []*cloudinstances.CloudInstance) []*renderableCloudInstance {
  	arr := make([]*renderableCloudInstance, len(instances))
  	for i, ci := range instances {
  		arr[i] = &renderableCloudInstance{
  			ID:            ci.ID,
  			Status:        ci.Status,
  			Roles:         ci.Roles,
  			InternalIP:    ci.PrivateIP,
  			ExternalIP:    ci.ExternalIP,
  			InstanceGroup: ci.CloudInstanceGroup.HumanName,
  			MachineType:   ci.MachineType,
  			State:         string(ci.State),
  		}
  		if ci.Node != nil {
  			arr[i].NodeName = ci.Node.Name
  		}
  	}
  	return arr
  }
  