MINOR: cluster: removing storage upon cluster removal

Author: prometherion

configuration/cluster_sync.go

@@ -36,9 +36,10 @@ import (
 	"github.com/google/renameio"
 	client_native "github.com/haproxytech/client-native/v4"
 	"github.com/haproxytech/config-parser/v4/types"
-	"github.com/haproxytech/dataplaneapi/log"
 	jsoniter "github.com/json-iterator/go"
 
+	"github.com/haproxytech/dataplaneapi/log"
+
 	"github.com/haproxytech/dataplaneapi/haproxy"
 	"github.com/haproxytech/dataplaneapi/misc"
 )
@@ -226,6 +227,10 @@ func (c *ClusterSync) monitorBootstrapKey() {
 				log.Error(errStorageDir)
 				continue
 			}
+			// Init NOTICE file to inform user that the cluster storage folder is programmatically managed by Fusion API
+			if errStorageInit := InitStorageNoticeFile(data["storage-dir"]); errStorageInit != nil {
+				log.Warningf("unable to create notice file, %s: skipping it", errStorageInit.Error())
+			}
 			url := fmt.Sprintf("%s://%s", data["schema"], data["address"])
 			c.cfg.Cluster.URL.Store(url)
 			c.cfg.Cluster.Port.Store(func() int {

configuration/misc.go

@@ -23,10 +23,12 @@ import (
 	"os"
 	"path"
 	"strconv"
+	"strings"
 	"syscall"
 	"time"
 
 	"github.com/go-openapi/strfmt"
+	"github.com/google/renameio"
 	"github.com/haproxytech/client-native/v4/misc"
 	"github.com/haproxytech/client-native/v4/storage"
 	jsoniter "github.com/json-iterator/go"
@@ -82,6 +84,20 @@ func fileExists(filename string) bool {
 	return !info.IsDir()
 }
 
+func RemoveStorageFolder(storageDir string) error {
+	return os.RemoveAll(storageDir)
+}
+
+func InitStorageNoticeFile(storageDir string) error {
+	content := strings.Builder{}
+
+	_, _ = fmt.Fprintf(&content, "# *********************************************************************************\n")
+	_, _ = fmt.Fprintf(&content, "# NOTE: This storage folder contains files managed by HAProxy Fusion Control Plane:\n")
+	_, _ = fmt.Fprintf(&content, "#       manual edits may cause issues and misconfigurations.\n")
+
+	return renameio.WriteFile(path.Join(storageDir, "NOTICE"), []byte(content.String()), os.ModePerm)
+}
+
 func CheckIfStorageDirIsOK(storageDir string, config *Configuration) error {
 	if storageDir == "" {
 		return errors.New("storage-dir in bootstrap key is empty")

handlers/cluster.go

@@ -130,7 +130,10 @@ func (h *CreateClusterHandlerImpl) Handle(params cluster.PostClusterParams, prin
 			log.Warningf("configured storage dir incompatible with cluster configuration: %s", errStorageDir)
 			return h.err409(errStorageDir, nil)
 		}
-
+		// Init NOTICE file to inform user that the cluster storage folder is programmatically managed by Fusion API
+		if errStorageInit := configuration.InitStorageNoticeFile(key["storage-dir"]); errStorageInit != nil {
+			log.Warningf("unable to create notice file, %s: skipping it", errStorageInit.Error())
+		}
 		// enforcing API advertising options
 		if a := params.AdvertisedAddress; a != nil {
 			h.Config.APIOptions.APIAddress = *a
@@ -176,18 +179,18 @@ func (h *DeleteClusterHandlerImpl) Handle(params cluster.DeleteClusterParams, pr
 		if params.Configuration == nil || *params.Configuration != "keep" {
 			log.Warning("clearing configuration as requested")
 
-			configuration, err := h.Client.Configuration()
+			conf, err := h.Client.Configuration()
 			if err != nil {
 				return h.err500(err, nil)
 			}
-			version, errVersion := configuration.GetVersion("")
+			version, errVersion := conf.GetVersion("")
 			if errVersion != nil || version < 1 {
 				// silently fallback to 1
 				version = 1
 			}
 
 			config := fmt.Sprintf(DummyConfig, time.Now().Format("01-02-2006 15:04:05 MST"), h.Config.Name.Load())
-			if err = configuration.PostRawConfiguration(&config, version, true); err != nil {
+			if err = conf.PostRawConfiguration(&config, version, true); err != nil {
 				return h.err500(err, nil)
 			}
 
@@ -196,6 +199,13 @@ func (h *DeleteClusterHandlerImpl) Handle(params cluster.DeleteClusterParams, pr
 			if err != nil {
 				return h.err500(err, nil)
 			}
+			// Deleting the storage directory used by Fusion:
+			// avoiding at all entering any nil pointer dereference.
+			if storageData := h.Config.GetStorageData(); storageData != nil && storageData.Cluster != nil && storageData.Cluster.StorageDir != nil {
+				if storageErr := configuration.RemoveStorageFolder(*storageData.Cluster.StorageDir); storageErr != nil {
+					log.Warningf("failed to clean-up the cluster storage directory: %s", storageErr.Error())
+				}
+			}
 		}
 		h.Config.Cluster.BootstrapKey.Store("")
 		h.Config.Mode.Store(configuration.ModeSingle)