Add --no-default-storage-location flag to velero install to enable velero deployment without default BSL (#1931)

This closes #1853.

Signed-off-by: Yunqian <specyq@gmail.com>

pkg/cmd/cli/install/install.go

@@ -65,6 +65,7 @@ type InstallOptions struct {
 	UseVolumeSnapshots                bool
 	DefaultResticMaintenanceFrequency time.Duration
 	Plugins                           flag.StringArray
+	NoDefaultBackupLocation           bool
 }
 
 // BindFlags adds command line values to the options struct.
@@ -73,6 +74,7 @@ func (o *InstallOptions) BindFlags(flags *pflag.FlagSet) {
 	flags.StringVar(&o.BucketName, "bucket", o.BucketName, "name of the object storage bucket where backups should be stored")
 	flags.StringVar(&o.SecretFile, "secret-file", o.SecretFile, "file containing credentials for backup and volume provider. If not specified, --no-secret must be used for confirmation. Optional.")
 	flags.BoolVar(&o.NoSecret, "no-secret", o.NoSecret, "flag indicating if a secret should be created. Must be used as confirmation if --secret-file is not provided. Optional.")
+	flags.BoolVar(&o.NoDefaultBackupLocation, "no-default-backup-location", o.NoDefaultBackupLocation, "flag indicating if a default backup location should be created. Must be used as confirmation if --bucket or --provider are not provided. Optional.")
 	flags.StringVar(&o.Image, "image", o.Image, "image to use for the Velero and restic server pods. Optional.")
 	flags.StringVar(&o.Prefix, "prefix", o.Prefix, "prefix under which all Velero data should be stored within the bucket. Optional.")
 	flags.Var(&o.PodAnnotations, "pod-annotations", "annotations to add to the Velero and restic pods. Optional. Format is key1=value1,key2=value2")
@@ -114,7 +116,8 @@ func NewInstallOptions() *InstallOptions {
 		ResticPodCPULimit:         install.DefaultResticPodCPULimit,
 		ResticPodMemLimit:         install.DefaultResticPodMemLimit,
 		// Default to creating a VSL unless we're told otherwise
-		UseVolumeSnapshots: true,
+		UseVolumeSnapshots:      true,
+		NoDefaultBackupLocation: false,
 	}
 }
 
@@ -158,6 +161,7 @@ func (o *InstallOptions) AsVeleroOptions() (*install.VeleroOptions, error) {
 		VSLConfig:                         o.VolumeSnapshotConfig.Data(),
 		DefaultResticMaintenanceFrequency: o.DefaultResticMaintenanceFrequency,
 		Plugins:                           o.Plugins,
+		NoDefaultBackupLocation:           o.NoDefaultBackupLocation,
 	}, nil
 }
 
@@ -264,6 +268,11 @@ func (o *InstallOptions) Run(c *cobra.Command, f client.Factory) error {
 	if o.SecretFile == "" {
 		fmt.Printf("\nNo secret file was specified, no Secret created.\n\n")
 	}
+
+	if o.NoDefaultBackupLocation {
+		fmt.Printf("\nNo bucket and provider were specified, no default backup storage location created.\n\n")
+	}
+
 	fmt.Printf("Velero is installed! ⛵ Use 'kubectl logs deployment/velero -n %s' to view the status.\n", o.Namespace)
 	return nil
 }
@@ -280,10 +289,6 @@ func (o *InstallOptions) Validate(c *cobra.Command, args []string, f client.Fact
 		return err
 	}
 
-	if o.BucketName == "" {
-		return errors.New("--bucket is required")
-	}
-
 	// Our main 3 providers don't support bucket names starting with a dash, and a bucket name starting with one
 	// can indicate that an environment variable was left blank.
 	// This case will help catch that error
@@ -291,8 +296,44 @@ func (o *InstallOptions) Validate(c *cobra.Command, args []string, f client.Fact
 		return errors.Errorf("Bucket names cannot begin with a dash. Bucket name was: %s", o.BucketName)
 	}
 
-	if o.ProviderName == "" {
-		return errors.New("--provider is required")
+	if o.NoDefaultBackupLocation {
+
+		if o.BucketName != "" {
+			return errors.New("Cannot use both --bucket and --no-default-backup-location at the same time")
+		}
+
+		if o.Prefix != "" {
+			return errors.New("Cannot use both --prefix and --no-default-backup-location at the same time")
+		}
+
+		if o.BackupStorageConfig.String() != "" {
+			return errors.New("Cannot use both --backup-location-config and --no-default-backup-location at the same time")
+		}
+	} else {
+		if o.ProviderName == "" {
+			return errors.New("--provider is required")
+		}
+
+		if o.BucketName == "" {
+			return errors.New("--bucket is required")
+		}
+
+	}
+
+	if o.UseVolumeSnapshots {
+		if o.ProviderName == "" {
+			return errors.New("--provider is required when --use-volume-snapshots is set to true")
+		}
+	} else {
+		if o.VolumeSnapshotConfig.String() != "" {
+			return errors.New("--snapshot-location-config must be empty when --use-volume-snapshots=false")
+		}
+	}
+
+	if o.NoDefaultBackupLocation && !o.UseVolumeSnapshots {
+		if o.ProviderName != "" {
+			return errors.New("--provider must be empty when using --no-default-backup-location and --use-volume-snapshots=false")
+		}
 	}
 
 	switch {