pkg/destroy/libvirt: Add behind a libvirt_destroy build tag

cmd/openshift-install/main.go

@@ -9,6 +9,7 @@ import (
 	"github.com/openshift/installer/pkg/asset"
 	"github.com/openshift/installer/pkg/asset/stock"
 	"github.com/openshift/installer/pkg/destroy"
+	_ "github.com/openshift/installer/pkg/destroy/libvirt"
 )
 
 var (
@@ -77,7 +78,7 @@ func main() {
 			}
 		}
 	case destroyCommand.FullCommand():
-		destroyer, err := destroy.NewDestroyer(l, *dirFlag)
+		destroyer, err := destroy.New(l, *dirFlag)
 		if err != nil {
 			log.Fatalf("failed to create destroyer: %v", err)
 			os.Exit(1)

docs/dev/dependencies.md

@@ -10,12 +10,16 @@ The following dependencies must be installed on your system before you can build
 sudo dnf install golang-bin gcc-c++
 ```
 
+If you need support for [libvirt destroy](libvirt-howto#cleanup), you should also install `libvirt-devel`.
+
 ### CentOS, RHEL
 
 ```sh
 sudo yum install golang-bin gcc-c++
 ```
 
+If you need support for [libvirt destroy](libvirt-howto#cleanup), you should also install `libvirt-devel`.
+
 ## Go
 
 We follow a hard flattening approach; i.e. direct and inherited dependencies are installed in the base `vendor/`.

docs/dev/libvirt-howto.md

@@ -184,6 +184,12 @@ EOF
 ## Build and run the installer
 
 With [libvirt configured](#install-and-enable-libvirt), you can proceed with [the usual quick-start](../../README.md#quick-start).
+Set `TAGS` when building if you need `destroy-cluster` support for libvirt; this is not enabled by default because it requires [cgo][]:
+
+```sh
+TAGS=libvirt_destroy hack/build.sh
+```
+
 To avoid being prompted repeatedly, you can set [environment variables](../user/environment-variables.md) to reflect your libvirt choices.  For example, selecting libvirt, setting [our earlier name choices](#pick-names), [our pull secret](#get-a-pull-secret), and telling both the installer and the machine-API operator to contact `libvirtd` at [the usual libvirt IP](#firewall), you can use:
 
 ```sh
@@ -196,9 +202,13 @@ export OPENSHIFT_INSTALL_LIBVIRT_URI=qemu+tcp://192.168.122.1/system
 
 ## Cleanup
 
-Be sure to destroy your cluster when you're done with it, or else you will need to manually use `virsh` to clean up the leaked resources.
-The [`virsh-cleanup`](../../scripts/maintenance/virsh-cleanup.sh) script may help with this, but note it will currently destroy *all* libvirt resources.
-We plan on adding `openshift-install destroy-cluster` support for libvirt in the near future.
+If you compiled with `libvirt_destroy`, you can use:
+
+```sh
+openshift-install destroy-cluster
+```
+
+If you did not compile with `libvirt_destroy`, you can use [`virsh-cleanup.sh`](../../scripts/maintenance/virsh-cleanup.sh), but note it will currently destroy *all* libvirt resources.
 
 ### Firewall
 
@@ -328,6 +338,7 @@ If your issue is not reported, please do.
 [arch_firewall_superuser]: https://superuser.com/questions/1063240/libvirt-failed-to-initialize-a-valid-firewall-backend
 [brokenmacosissue201]: https://github.com/openshift/installer/issues/201
 [bugzilla_libvirt_race]: https://bugzilla.redhat.com/show_bug.cgi?id=1576464
+[cgo]: https://golang.org/cmd/cgo/
 [issues_libvirt]: https://github.com/openshift/installer/issues?utf8=%E2%9C%93&q=is%3Aissue+is%3Aopen+libvirt
 [libvirt_selinux_issues]: https://github.com/dmacvicar/terraform-provider-libvirt/issues/142#issuecomment-409040151
 [tfprovider_libvirt_race]: https://github.com/dmacvicar/terraform-provider-libvirt/issues/402#issuecomment-419500064

hack/build.sh

@@ -5,11 +5,12 @@ set -ex
 cd "$(dirname "$0")/.."
 
 MODE="${MODE:-release}"
-TAGS=
+TAGS="${TAGS:-}"
+export CGO_ENABLED=0
 
 case "${MODE}" in
 release)
-	TAGS=release
+	TAGS="${TAGS} release"
 	GOPATH="${PWD}/vendor:${GOPATH}" go generate ./data
 	;;
 dev)
@@ -19,4 +20,9 @@ dev)
 	exit 1
 esac
 
-CGO_ENABLED=0 go build -tags "${TAGS}" -o ./bin/openshift-install ./cmd/openshift-install
+if (echo "${TAGS}" | grep -q 'libvirt_destroy')
+then
+	export CGO_ENABLED=1
+fi
+
+go build -tags "${TAGS}" -o ./bin/openshift-install ./cmd/openshift-install

pkg/destroy/aws.go

@@ -0,0 +1,30 @@
+package destroy
+
+import (
+	"os"
+
+	atd "github.com/openshift/hive/contrib/pkg/awstagdeprovision"
+	"github.com/openshift/installer/pkg/types"
+	log "github.com/sirupsen/logrus"
+)
+
+// NewAWS returns an AWS destroyer from ClusterMetadata.
+func NewAWS(level log.Level, metadata *types.ClusterMetadata) (Destroyer, error) {
+	return &atd.ClusterUninstaller{
+		Filters:     metadata.ClusterPlatformMetadata.AWS.Identifier,
+		Region:      metadata.ClusterPlatformMetadata.AWS.Region,
+		ClusterName: metadata.ClusterName,
+		Logger: log.NewEntry(&log.Logger{
+			Out: os.Stdout,
+			Formatter: &log.TextFormatter{
+				FullTimestamp: true,
+			},
+			Hooks: make(log.LevelHooks),
+			Level: level,
+		}),
+	}, nil
+}
+
+func init() {
+	Registry["aws"] = NewAWS
+}

pkg/destroy/destroyer.go

@@ -4,10 +4,8 @@ import (
 	"encoding/json"
 	"fmt"
 	"io/ioutil"
-	"os"
 	"path/filepath"
 
-	atd "github.com/openshift/hive/contrib/pkg/awstagdeprovision"
 	log "github.com/sirupsen/logrus"
 
 	"github.com/openshift/installer/pkg/asset/metadata"
@@ -20,60 +18,33 @@ type Destroyer interface {
 	Run() error
 }
 
-// NewDestroyer returns Destroyer based on `metadata.json` in `rootDir`.
-func NewDestroyer(level log.Level, rootDir string) (Destroyer, error) {
+// NewFunc is an interface for creating platform-specific destroyers.
+type NewFunc func(level log.Level, metadata *types.ClusterMetadata) (Destroyer, error)
+
+// Registry maps ClusterMetadata.Platform() to per-platform Destroyer creators.
+var Registry = make(map[string]NewFunc)
+
+// New returns a Destroyer based on `metadata.json` in `rootDir`.
+func New(level log.Level, rootDir string) (Destroyer, error) {
+	path := filepath.Join(rootDir, metadata.MetadataFilename)
 	raw, err := ioutil.ReadFile(filepath.Join(rootDir, metadata.MetadataFilename))
 	if err != nil {
 		return nil, err
 	}
 
-	var cmetadata types.ClusterMetadata
+	var cmetadata *types.ClusterMetadata
 	if err := json.Unmarshal(raw, &cmetadata); err != nil {
 		return nil, err
 	}
 
-	var ret Destroyer
-	switch {
-	case cmetadata.ClusterPlatformMetadata.AWS != nil:
-		ret = NewAWSDestroyer(level, &cmetadata)
-	case cmetadata.ClusterPlatformMetadata.Libvirt != nil:
-		// ret = NewLibvirtDestroyer(level, &cmetadata)
-		return nil, fmt.Errorf("libvirt destroyer is not yet supported")
-	default:
-		return nil, fmt.Errorf("couldn't find Destroyer for %q", metadata.MetadataFilename)
+	platform := cmetadata.Platform()
+	if platform == "" {
+		return nil, fmt.Errorf("no platform configured in %q", path)
 	}
-	return ret, nil
-}
-
-// // NewLibvirtDestroyer returns libvirt Uninstaller from ClusterMetadata.
-// func NewLibvirtDestroyer(level log.Level, metadata *types.ClusterMetadata) *lpd.ClusterUninstaller {
-// 	return &lpd.ClusterUninstaller{
-// 		LibvirtURI: metadata.ClusterPlatformMetadata.Libvirt.URI,
-// 		Filter:     lpd.AlwaysTrueFilter(), //TODO: change to ClusterNamePrefixFilter when all resources are prefixed.
-// 		Logger: log.NewEntry(&log.Logger{
-// 			Out: os.Stdout,
-// 			Formatter: &log.TextFormatter{
-// 				FullTimestamp: true,
-// 			},
-// 			Hooks: make(log.LevelHooks),
-// 			Level: level,
-// 		}),
-// 	}
-// }
 
-// NewAWSDestroyer returns aws Uninstaller from ClusterMetadata.
-func NewAWSDestroyer(level log.Level, metadata *types.ClusterMetadata) *atd.ClusterUninstaller {
-	return &atd.ClusterUninstaller{
-		Filters:     metadata.ClusterPlatformMetadata.AWS.Identifier,
-		Region:      metadata.ClusterPlatformMetadata.AWS.Region,
-		ClusterName: metadata.ClusterName,
-		Logger: log.NewEntry(&log.Logger{
-			Out: os.Stdout,
-			Formatter: &log.TextFormatter{
-				FullTimestamp: true,
-			},
-			Hooks: make(log.LevelHooks),
-			Level: level,
-		}),
+	creator, ok := Registry[platform]
+	if !ok {
+		return nil, fmt.Errorf("no destroyers registered for %q", platform)
 	}
+	return creator(level, cmetadata)
 }

pkg/destroy/libvirt/doc.go

@@ -0,0 +1,2 @@
+// Package libvirt provides a cluster-destroyer for libvirt clusters.
+package libvirt

pkg/destroy/libvirt/libvirt_prefix_deprovision.go

@@ -1,3 +1,5 @@
+// +build libvirt_destroy
+
 package libvirt
 
 import (
@@ -6,6 +8,8 @@ import (
 	"time"
 
 	libvirt "github.com/libvirt/libvirt-go"
+	"github.com/openshift/installer/pkg/destroy"
+	"github.com/openshift/installer/pkg/types"
 	log "github.com/sirupsen/logrus"
 	"k8s.io/apimachinery/pkg/util/wait"
 )
@@ -239,3 +243,19 @@ func deleteNetwork(conn *libvirt.Connect, filter filterFunc, logger log.FieldLog
 	}
 	return true, nil
 }
+
+// New returns libvirt Uninstaller from ClusterMetadata.
+func New(level log.Level, metadata *types.ClusterMetadata) (destroy.Destroyer, error) {
+	return &ClusterUninstaller{
+		LibvirtURI: metadata.ClusterPlatformMetadata.Libvirt.URI,
+		Filter:     AlwaysTrueFilter(), //TODO: change to ClusterNamePrefixFilter when all resources are prefixed.
+		Logger: log.NewEntry(&log.Logger{
+			Out: os.Stdout,
+			Formatter: &log.TextFormatter{
+				FullTimestamp: true,
+			},
+			Hooks: make(log.LevelHooks),
+			Level: level,
+		}),
+	}, nil
+}

pkg/destroy/libvirt/register.go

@@ -0,0 +1,11 @@
+// +build libvirt_destroy
+
+package libvirt
+
+import (
+	"github.com/openshift/installer/pkg/destroy"
+)
+
+func init() {
+	destroy.Registry["libvirt"] = New
+}

pkg/types/clustermetadata.go

@@ -13,6 +13,22 @@ type ClusterPlatformMetadata struct {
 	Libvirt *ClusterLibvirtPlatformMetadata `json:"libvirt,omitempty"`
 }
 
+// Platform returns a string representation of the platform
+// (e.g. "aws" if AWS is non-nil).  It returns an empty string if no
+// platform is configured.
+func (cpm *ClusterPlatformMetadata) Platform() string {
+	if cpm == nil {
+		return ""
+	}
+	if cpm.AWS != nil {
+		return "aws"
+	}
+	if cpm.Libvirt != nil {
+		return "libvirt"
+	}
+	return ""
+}
+
 // ClusterAWSPlatformMetadata contains AWS metadata.
 type ClusterAWSPlatformMetadata struct {
 	Region string `json:"region"`