registry.go

package registry

import (
	cryptorand "crypto/rand"
	"encoding/base64"
	"fmt"
	"io"
	"io/ioutil"
	"os"
	"path"
	"strconv"
	"strings"

	"github.com/spf13/cobra"
	"k8s.io/apimachinery/pkg/api/errors"
	"k8s.io/apimachinery/pkg/api/resource"
	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
	"k8s.io/apimachinery/pkg/runtime"
	"k8s.io/apimachinery/pkg/util/intstr"
	kapi "k8s.io/kubernetes/pkg/api"
	"k8s.io/kubernetes/pkg/apis/extensions"
	kcoreclient "k8s.io/kubernetes/pkg/client/clientset_generated/internalclientset/typed/core/internalversion"
	kcmdutil "k8s.io/kubernetes/pkg/kubectl/cmd/util"

	authapi "github.com/openshift/origin/pkg/authorization/apis/authorization"
	"github.com/openshift/origin/pkg/cmd/templates"
	cmdutil "github.com/openshift/origin/pkg/cmd/util"
	"github.com/openshift/origin/pkg/cmd/util/clientcmd"
	"github.com/openshift/origin/pkg/cmd/util/variable"

	configcmd "github.com/openshift/origin/pkg/config/cmd"
	deployapi "github.com/openshift/origin/pkg/deploy/apis/apps"
	"github.com/openshift/origin/pkg/generate/app"
)

var (
	registryLong = templates.LongDesc(`
		Install or configure an integrated Docker registry

		This command sets up a Docker registry integrated with your cluster to provide notifications when
		images are pushed. With no arguments, the command will check for the existing registry service
		called 'docker-registry' and try to create it. If you want to test whether the registry has
		been created add the --dry-run flag and the command will exit with 1 if the registry does not
		exist.

		To run a highly available registry, you should be using a remote storage mechanism like an
		object store (several are supported by the Docker registry). The default Docker registry image
		is configured to accept configuration as environment variables - refer to the configuration file in
		that image for more on setting up alternative storage. Once you've made those changes, you can
		pass --replicas=2 or higher to ensure you have failover protection. The default registry setup
		uses a local volume and the data will be lost if you delete the running pod.

		If multiple ports are specified using the option --ports, the first specified port will be
		chosen for use as the REGISTRY_HTTP_ADDR and will be passed to Docker registry.

		NOTE: This command is intended to simplify the tasks of setting up a Docker registry in a new
		installation. Some configuration beyond this command is still required to make
		your registry persist data.`)

	registryExample = templates.Examples(`
		# Check if default Docker registry ("docker-registry") has been created
	  %[1]s %[2]s --dry-run

	  # See what the registry will look like if created
	  %[1]s %[2]s -o yaml

	  # Create a registry with two replicas if it does not exist
	  %[1]s %[2]s --replicas=2

	  # Use a different registry image
	  %[1]s %[2]s --images=myrepo/docker-registry:mytag

	  # Enforce quota and limits on images
	  %[1]s %[2]s --enforce-quota`)
)

// RegistryOptions contains the configuration for the registry as well as any other
// helpers required to run the command.
type RegistryOptions struct {
	Config *RegistryConfig

	// helpers required for Run.
	factory       *clientcmd.Factory
	cmd           *cobra.Command
	out           io.Writer
	label         map[string]string
	nodeSelector  map[string]string
	ports         []kapi.ContainerPort
	namespace     string
	serviceClient kcoreclient.ServicesGetter
	image         string
}

// RegistryConfig contains configuration for the registry that will be created.
type RegistryConfig struct {
	Action configcmd.BulkAction

	Name           string
	Type           string
	ImageTemplate  variable.ImageTemplate
	Ports          string
	Replicas       int32
	Labels         string
	Volume         string
	HostMount      string
	DryRun         bool
	Selector       string
	ServiceAccount string
	DaemonSet      bool
	EnforceQuota   bool

	// SupplementalGroups is list of int64, however cobra does not have appropriate func
	// for that type list.
	SupplementalGroups []string
	FSGroup            string

	ServingCertPath string
	ServingKeyPath  string

	ClusterIP string

	// TODO: accept environment values.
}

// randomSecretSize is the number of random bytes to generate.
const randomSecretSize = 32

const (
	defaultLabel = "docker-registry=default"
	defaultPort  = 5000
	/* TODO: `/healthz` has been deprecated by `/`; keep it temporarily for backwards compatibility until
	 * a next major release with a strict requirement on newer registry image
	 * NOTE that `/` is supported since ose `v3.1.1.0`
	 * To make the transition safe, we could change `HTTPGetAction` to an `ExecAction` which would first curl
	 * `/` and then fallback to `/healthz` if unreachable. Reachable endpoint could be cached on tmpfs inside
	 * a container and be used on subsequent checks. */
	healthzRoute               = "/healthz"
	healthzRouteTimeoutSeconds = 5
	// this is the official private certificate path on Red Hat distros, and is at least structurally more
	// correct than ubuntu based distributions which don't distinguish between public and private certs.
	// Since Origin is CentOS based this is more likely to work.  Ubuntu images should symlink this directory
	// into /etc/ssl/certs to be compatible.
	defaultCertificateDir = "/etc/pki/tls/private"
)

// NewCmdRegistry implements the OpenShift cli registry command
func NewCmdRegistry(f *clientcmd.Factory, parentName, name string, out, errout io.Writer) *cobra.Command {
	cfg := &RegistryConfig{
		ImageTemplate:  variable.NewDefaultImageTemplate(),
		Name:           "registry",
		Labels:         defaultLabel,
		Ports:          strconv.Itoa(defaultPort),
		Volume:         "/registry",
		ServiceAccount: "registry",
		Replicas:       1,
		EnforceQuota:   false,
	}

	cmd := &cobra.Command{
		Use:     name,
		Short:   "Install the integrated Docker registry",
		Long:    registryLong,
		Example: fmt.Sprintf(registryExample, parentName, name),
		Run: func(cmd *cobra.Command, args []string) {
			opts := &RegistryOptions{
				Config: cfg,
			}
			kcmdutil.CheckErr(opts.Complete(f, cmd, out, errout, args))
			err := opts.RunCmdRegistry()
			if err == cmdutil.ErrExit {
				os.Exit(1)
			}
			kcmdutil.CheckErr(err)
		},
	}

	cmd.Flags().StringVar(&cfg.Type, "type", "docker-registry", "The registry image to use - if you specify --images this flag may be ignored.")
	cmd.Flags().StringVar(&cfg.ImageTemplate.Format, "images", cfg.ImageTemplate.Format, "The image to base this registry on - ${component} will be replaced with --type")
	cmd.Flags().BoolVar(&cfg.ImageTemplate.Latest, "latest-images", cfg.ImageTemplate.Latest, "If true, attempt to use the latest image for the registry instead of the latest release.")
	cmd.Flags().StringVar(&cfg.Ports, "ports", cfg.Ports, fmt.Sprintf("A comma delimited list of ports or port pairs to expose on the registry pod. The default is set for %d.", defaultPort))
	cmd.Flags().Int32Var(&cfg.Replicas, "replicas", cfg.Replicas, "The replication factor of the registry; commonly 2 when high availability is desired.")
	cmd.Flags().StringVar(&cfg.Labels, "labels", cfg.Labels, "A set of labels to uniquely identify the registry and its components.")
	cmd.Flags().StringVar(&cfg.Volume, "volume", cfg.Volume, "The volume path to use for registry storage; defaults to /registry which is the default for origin-docker-registry.")
	cmd.Flags().StringVar(&cfg.HostMount, "mount-host", cfg.HostMount, "If set, the registry volume will be created as a host-mount at this path.")
	cmd.Flags().Bool("create", false, "deprecated; this is now the default behavior")
	cmd.Flags().StringVar(&cfg.ServiceAccount, "service-account", cfg.ServiceAccount, "Name of the service account to use to run the registry pod.")
	cmd.Flags().StringVar(&cfg.Selector, "selector", cfg.Selector, "Selector used to filter nodes on deployment. Used to run registries on a specific set of nodes.")
	cmd.Flags().StringVar(&cfg.ServingCertPath, "tls-certificate", cfg.ServingCertPath, "An optional path to a PEM encoded certificate (which may contain the private key) for serving over TLS")
	cmd.Flags().StringVar(&cfg.ServingKeyPath, "tls-key", cfg.ServingKeyPath, "An optional path to a PEM encoded private key for serving over TLS")
	cmd.Flags().StringSliceVar(&cfg.SupplementalGroups, "supplemental-groups", cfg.SupplementalGroups, "Specify supplemental groups which is an array of ID's that grants group access to registry shared storage")
	cmd.Flags().StringVar(&cfg.FSGroup, "fs-group", "", "Specify fsGroup which is an ID that grants group access to registry block storage")
	cmd.Flags().BoolVar(&cfg.DaemonSet, "daemonset", cfg.DaemonSet, "If true, use a daemonset instead of a deployment config.")
	cmd.Flags().BoolVar(&cfg.EnforceQuota, "enforce-quota", cfg.EnforceQuota, "If true, the registry will refuse to write blobs if they exceed quota limits")

	cfg.Action.BindForOutput(cmd.Flags())
	cmd.Flags().String("output-version", "", "The preferred API versions of the output objects")

	return cmd
}

// Complete completes any options that are required by validate or run steps.
func (opts *RegistryOptions) Complete(f *clientcmd.Factory, cmd *cobra.Command, out, errout io.Writer, args []string) error {
	if len(args) > 0 {
		return kcmdutil.UsageError(cmd, "No arguments are allowed to this command")
	}

	opts.image = opts.Config.ImageTemplate.ExpandOrDie(opts.Config.Type)

	opts.label = map[string]string{
		"docker-registry": "default",
	}
	if opts.Config.Labels != defaultLabel {
		valid, remove, err := app.LabelsFromSpec(strings.Split(opts.Config.Labels, ","))
		if err != nil {
			return err
		}
		if len(remove) > 0 {
			return kcmdutil.UsageError(cmd, "You may not pass negative labels in %q", opts.Config.Labels)
		}
		opts.label = valid
	}

	opts.nodeSelector = map[string]string{}
	if len(opts.Config.Selector) > 0 {
		valid, remove, err := app.LabelsFromSpec(strings.Split(opts.Config.Selector, ","))
		if err != nil {
			return err
		}
		if len(remove) > 0 {
			return kcmdutil.UsageError(cmd, "You may not pass negative labels in selector %q", opts.Config.Selector)
		}
		opts.nodeSelector = valid
	}

	if len(opts.Config.FSGroup) > 0 {
		if _, err := strconv.ParseInt(opts.Config.FSGroup, 10, 64); err != nil {
			return kcmdutil.UsageError(cmd, "invalid group ID %q specified for fsGroup (%v)", opts.Config.FSGroup, err)
		}
	}

	if len(opts.Config.SupplementalGroups) > 0 {
		for _, v := range opts.Config.SupplementalGroups {
			if val, err := strconv.ParseInt(v, 10, 64); err != nil || val == 0 {
				return kcmdutil.UsageError(cmd, "invalid group ID %q specified for supplemental group (%v)", v, err)
			}
		}
	}
	if len(opts.Config.SupplementalGroups) > 0 && len(opts.Config.FSGroup) > 0 {
		return kcmdutil.UsageError(cmd, "fsGroup and supplemental groups cannot be specified both at the same time")
	}

	var portsErr error
	if opts.ports, portsErr = app.ContainerPortsFromString(opts.Config.Ports); portsErr != nil {
		return portsErr
	}

	var nsErr error
	if opts.namespace, _, nsErr = f.DefaultNamespace(); nsErr != nil {
		return fmt.Errorf("error getting namespace: %v", nsErr)
	}

	_, kClient, kClientErr := f.Clients()
	if kClientErr != nil {
		return fmt.Errorf("error getting client: %v", kClientErr)
	}
	opts.serviceClient = kClient.Core()

	opts.Config.Action.Bulk.Mapper = clientcmd.ResourceMapper(f)
	opts.Config.Action.Out, opts.Config.Action.ErrOut = out, errout
	opts.Config.Action.Bulk.Op = configcmd.Create
	opts.out = out
	opts.cmd = cmd
	opts.factory = f

	return nil
}

// RunCmdRegistry contains all the necessary functionality for the OpenShift cli registry command
func (opts *RegistryOptions) RunCmdRegistry() error {
	name := "docker-registry"

	var clusterIP string

	output := opts.Config.Action.ShouldPrint()
	generate := output
	service, err := opts.serviceClient.Services(opts.namespace).Get(name, metav1.GetOptions{})
	if err != nil {
		if !generate {
			if !errors.IsNotFound(err) {
				return fmt.Errorf("can't check for existing docker-registry %q: %v", name, err)
			}
			if opts.Config.Action.DryRun {
				return fmt.Errorf("Docker registry %q service does not exist", name)
			}
			generate = true
		}
	} else {
		clusterIP = service.Spec.ClusterIP
	}

	if !generate {
		fmt.Fprintf(opts.out, "Docker registry %q service exists\n", name)
		return nil
	}

	if len(opts.Config.ClusterIP) > 0 {
		clusterIP = opts.Config.ClusterIP
	}

	// create new registry
	secretEnv := app.Environment{}
	if len(opts.Config.ServiceAccount) == 0 {
		return fmt.Errorf("registry could not be created; a service account must be provided")
	}

	var servingCert, servingKey []byte
	if len(opts.Config.ServingCertPath) > 0 {
		data, err := ioutil.ReadFile(opts.Config.ServingCertPath)
		if err != nil {
			return fmt.Errorf("registry does not exist; could not load TLS certificate file %q: %v", opts.Config.ServingCertPath, err)
		}
		servingCert = data
	}
	if len(opts.Config.ServingKeyPath) > 0 {
		data, err := ioutil.ReadFile(opts.Config.ServingKeyPath)
		if err != nil {
			return fmt.Errorf("registry does not exist; could not load TLS private key file %q: %v", opts.Config.ServingKeyPath, err)
		}
		servingKey = data
	}

	env := app.Environment{}
	env.Add(secretEnv)

	env["REGISTRY_MIDDLEWARE_REPOSITORY_OPENSHIFT_ENFORCEQUOTA"] = fmt.Sprintf("%t", opts.Config.EnforceQuota)
	healthzPort := defaultPort
	if len(opts.ports) > 0 {
		healthzPort = int(opts.ports[0].ContainerPort)
		env["REGISTRY_HTTP_ADDR"] = fmt.Sprintf(":%d", healthzPort)
		env["REGISTRY_HTTP_NET"] = "tcp"
	}
	secrets, volumes, mounts, extraEnv, tls, err := generateSecretsConfig(opts.Config, servingCert, servingKey)
	if err != nil {
		return err
	}
	env.Add(extraEnv)

	livenessProbe := generateLivenessProbeConfig(healthzPort, tls)
	readinessProbe := generateReadinessProbeConfig(healthzPort, tls)

	mountHost := len(opts.Config.HostMount) > 0
	podTemplate := &kapi.PodTemplateSpec{
		ObjectMeta: metav1.ObjectMeta{Labels: opts.label},
		Spec: kapi.PodSpec{
			NodeSelector: opts.nodeSelector,
			Containers: []kapi.Container{
				{
					Name:  "registry",
					Image: opts.image,
					Ports: opts.ports,
					Env:   env.List(),
					VolumeMounts: append(mounts, kapi.VolumeMount{
						Name:      "registry-storage",
						MountPath: opts.Config.Volume,
					}),
					SecurityContext: &kapi.SecurityContext{
						Privileged: &mountHost,
					},
					LivenessProbe:  livenessProbe,
					ReadinessProbe: readinessProbe,
					Resources: kapi.ResourceRequirements{
						Requests: kapi.ResourceList{
							kapi.ResourceCPU:    resource.MustParse("100m"),
							kapi.ResourceMemory: resource.MustParse("256Mi"),
						},
					},
				},
			},
			Volumes: append(volumes, kapi.Volume{
				Name:         "registry-storage",
				VolumeSource: kapi.VolumeSource{},
			}),
			ServiceAccountName: opts.Config.ServiceAccount,
			SecurityContext:    generateSecurityContext(opts.Config),
		},
	}
	if mountHost {
		podTemplate.Spec.Volumes[len(podTemplate.Spec.Volumes)-1].HostPath = &kapi.HostPathVolumeSource{Path: opts.Config.HostMount}
	} else {
		podTemplate.Spec.Volumes[len(podTemplate.Spec.Volumes)-1].EmptyDir = &kapi.EmptyDirVolumeSource{}
	}

	objects := []runtime.Object{}
	for _, s := range secrets {
		objects = append(objects, s)
	}

	objects = append(objects,
		&kapi.ServiceAccount{ObjectMeta: metav1.ObjectMeta{Name: opts.Config.ServiceAccount}},
		&authapi.ClusterRoleBinding{
			ObjectMeta: metav1.ObjectMeta{Name: fmt.Sprintf("registry-%s-role", opts.Config.Name)},
			Subjects: []kapi.ObjectReference{
				{
					Kind:      "ServiceAccount",
					Name:      opts.Config.ServiceAccount,
					Namespace: opts.namespace,
				},
			},
			RoleRef: kapi.ObjectReference{
				Kind: "ClusterRole",
				Name: "system:registry",
			},
		},
	)

	if opts.Config.DaemonSet {
		objects = append(objects, &extensions.DaemonSet{
			ObjectMeta: metav1.ObjectMeta{
				Name:   name,
				Labels: opts.label,
			},
			Spec: extensions.DaemonSetSpec{
				Template: kapi.PodTemplateSpec{
					ObjectMeta: podTemplate.ObjectMeta,
					Spec:       podTemplate.Spec,
				},
			},
		})
	} else {
		objects = append(objects, &deployapi.DeploymentConfig{
			ObjectMeta: metav1.ObjectMeta{
				Name:   name,
				Labels: opts.label,
			},
			Spec: deployapi.DeploymentConfigSpec{
				Replicas: opts.Config.Replicas,
				Selector: opts.label,
				Triggers: []deployapi.DeploymentTriggerPolicy{
					{Type: deployapi.DeploymentTriggerOnConfigChange},
				},
				Template: podTemplate,
			},
		})
	}

	objects = app.AddServices(objects, true)

	// Set registry service's sessionAffinity to ClientIP to prevent push
	// failures due to a use of poorly consistent storage shared by
	// multiple replicas. Also reuse the cluster IP if provided to avoid
	// changing the internal value.
	for _, obj := range objects {
		switch t := obj.(type) {
		case *kapi.Service:
			t.Spec.SessionAffinity = kapi.ServiceAffinityClientIP
			t.Spec.ClusterIP = clusterIP
		}
	}

	// TODO: label all created objects with the same label
	list := &kapi.List{Items: objects}

	if opts.Config.Action.ShouldPrint() {
		mapper, _ := opts.factory.Object()
		opts.cmd.Flag("output-version").Value.Set("extensions/v1beta1,v1")
		fn := cmdutil.VersionedPrintObject(opts.factory.PrintObject, opts.cmd, mapper, opts.out)
		if err := fn(list); err != nil {
			return fmt.Errorf("unable to print object: %v", err)
		}
		return nil
	}

	if errs := opts.Config.Action.WithMessage(fmt.Sprintf("Creating registry %s", opts.Config.Name), "created").Run(list, opts.namespace); len(errs) > 0 {
		return cmdutil.ErrExit
	}
	return nil
}

func generateLivenessProbeConfig(port int, https bool) *kapi.Probe {
	probeConfig := generateProbeConfig(port, https)
	probeConfig.InitialDelaySeconds = 10

	return probeConfig
}

func generateReadinessProbeConfig(port int, https bool) *kapi.Probe {
	return generateProbeConfig(port, https)
}

func generateProbeConfig(port int, https bool) *kapi.Probe {
	var scheme kapi.URIScheme
	if https {
		scheme = kapi.URISchemeHTTPS
	}
	return &kapi.Probe{
		TimeoutSeconds: healthzRouteTimeoutSeconds,
		Handler: kapi.Handler{
			HTTPGet: &kapi.HTTPGetAction{
				Scheme: scheme,
				Path:   healthzRoute,
				Port:   intstr.FromInt(port),
			},
		},
	}
}

// generateSecretsConfig generates any Secret and Volume objects, such
// as the TLS serving cert that are necessary for the registry container.
// Runs true if the registry should be served over TLS.
func generateSecretsConfig(
	cfg *RegistryConfig, defaultCrt, defaultKey []byte,
) ([]*kapi.Secret, []kapi.Volume, []kapi.VolumeMount, app.Environment, bool, error) {
	var secrets []*kapi.Secret
	var volumes []kapi.Volume
	var mounts []kapi.VolumeMount
	extraEnv := app.Environment{}

	if len(defaultCrt) > 0 && len(defaultKey) == 0 {
		keys, err := cmdutil.PrivateKeysFromPEM(defaultCrt)
		if err != nil {
			return nil, nil, nil, nil, false, err
		}
		if len(keys) == 0 {
			return nil, nil, nil, nil, false, fmt.Errorf("the default cert must contain a private key")
		}
		defaultKey = keys
	}

	if len(defaultCrt) > 0 {
		secret := &kapi.Secret{
			ObjectMeta: metav1.ObjectMeta{
				Name: fmt.Sprintf("%s-certs", cfg.Name),
			},
			Type: kapi.SecretTypeTLS,
			Data: map[string][]byte{
				kapi.TLSCertKey:       defaultCrt,
				kapi.TLSPrivateKeyKey: defaultKey,
			},
		}
		secrets = append(secrets, secret)
		volume := kapi.Volume{
			Name: "server-certificate",
			VolumeSource: kapi.VolumeSource{
				Secret: &kapi.SecretVolumeSource{
					SecretName: secret.Name,
				},
			},
		}
		volumes = append(volumes, volume)

		mount := kapi.VolumeMount{
			Name:      volume.Name,
			ReadOnly:  true,
			MountPath: defaultCertificateDir,
		}
		mounts = append(mounts, mount)

		extraEnv.Add(app.Environment{
			"REGISTRY_HTTP_TLS_CERTIFICATE": path.Join(defaultCertificateDir, kapi.TLSCertKey),
			"REGISTRY_HTTP_TLS_KEY":         path.Join(defaultCertificateDir, kapi.TLSPrivateKeyKey),
		})
	}

	secretBytes := make([]byte, randomSecretSize)
	if _, err := cryptorand.Read(secretBytes); err != nil {
		return nil, nil, nil, nil, false, fmt.Errorf("registry does not exist; could not generate random bytes for HTTP secret: %v", err)
	}
	httpSecretString := base64.StdEncoding.EncodeToString(secretBytes)
	extraEnv["REGISTRY_HTTP_SECRET"] = httpSecretString

	return secrets, volumes, mounts, extraEnv, len(defaultCrt) > 0, nil
}

func generateSecurityContext(conf *RegistryConfig) *kapi.PodSecurityContext {
	result := &kapi.PodSecurityContext{}
	if len(conf.SupplementalGroups) > 0 {
		result.SupplementalGroups = []int64{}
		for _, val := range conf.SupplementalGroups {
			// The errors are handled by Complete()
			if groupID, err := strconv.ParseInt(val, 10, 64); err == nil {
				result.SupplementalGroups = append(result.SupplementalGroups, groupID)
			}
		}
	}
	if len(conf.FSGroup) > 0 {
		if groupID, err := strconv.ParseInt(conf.FSGroup, 10, 64); err == nil {
			result.FSGroup = &groupID
		}
	}
	return result
}