shell: return flag parse errors from every command (#12618)

* shell: return flag parse errors from every command

48 commands returned nil when their flags failed to parse, so a mistyped
flag printed the flag error but the command still counted as a success:
a piped weed shell run exited 0, the master maintenance loop logged no
error, and admin script jobs reported the line as done.

Return the parse error as s3.bucket.create (#12544) and the other shell
commands already do. TestCommandsReturnFlagParseErrors runs every
registered command with an unknown flag and fails for the 48 on master.

Signed-off-by: anant <170962632+antcybersec@users.noreply.github.com>

* shell: don't report -h as a failure

With the parse errors returned, -h on those commands now returns
flag.ErrHelp, so the shell printed "error: flag: help requested" and a
piped run exited 1. The flag package has already printed the usage, so
processEachCmd now treats flag.ErrHelp as success for every command.

Signed-off-by: anant <170962632+antcybersec@users.noreply.github.com>

* shell: keep the -h test beside the flag parse test

TestProcessEachCmdTreatsHelpAsSuccess covers the same change as
TestCommandsReturnFlagParseErrors, so it lives in the same new file and
shell_liner_test.go stays as it was.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

---------

Signed-off-by: anant <170962632+antcybersec@users.noreply.github.com>
Co-authored-by: anant <170962632+antcybersec@users.noreply.github.com>
Co-authored-by: Chris Lu <chrislusf@users.noreply.github.com>
Co-authored-by: Claude Opus 5.5 <noreply@anthropic.com>

weed/shell/command.go

@@ -1,6 +1,10 @@
 package shell
 
-import "io"
+import (
+	"errors"
+	"flag"
+	"io"
+)
 
 type command interface {
 	Name() string
@@ -19,3 +23,10 @@ const (
 	ResourceHeavy CommandTag = "resourceHeavy"
 	Hidden        CommandTag = "hidden"
 )
+
+// isHelpError reports whether a command only stopped because it was run
+// with -h: the flag package has already printed its usage, so this is not a
+// failure.
+func isHelpError(err error) bool {
+	return errors.Is(err, flag.ErrHelp)
+}

weed/shell/command_cluster_check.go

@@ -41,7 +41,7 @@ func (c *commandClusterCheck) Do(args []string, commandEnv *CommandEnv, writer i
 
 	clusterPsCommand := flag.NewFlagSet(c.Name(), flag.ContinueOnError)
 	if err = clusterPsCommand.Parse(args); err != nil {
-		return nil
+		return err
 	}
 
 	// collect topology information

weed/shell/command_cluster_ps.go

@@ -44,7 +44,7 @@ func (c *commandClusterPs) Do(args []string, commandEnv *CommandEnv, writer io.W
 
 	clusterPsCommand := flag.NewFlagSet(c.Name(), flag.ContinueOnError)
 	if err = clusterPsCommand.Parse(args); err != nil {
-		return nil
+		return err
 	}
 
 	listClusterNodes := func(clientType string) ([]*master_pb.ListClusterNodesResponse_ClusterNode, error) {

weed/shell/command_cluster_raft_add.go

@@ -39,7 +39,7 @@ func (c *commandRaftServerAdd) Do(args []string, commandEnv *CommandEnv, writer
 	serverAddress := raftServerAddCommand.String("address", "", "server grpc address")
 	serverVoter := raftServerAddCommand.Bool("voter", true, "assign it a vote")
 	if err = raftServerAddCommand.Parse(args); err != nil {
-		return nil
+		return err
 	}
 
 	if *serverId == "" || *serverAddress == "" {

weed/shell/command_cluster_raft_ps.go

@@ -35,7 +35,7 @@ func (c *commandRaftClusterPs) Do(args []string, commandEnv *CommandEnv, writer
 
 	raftClusterPsCommand := flag.NewFlagSet(c.Name(), flag.ContinueOnError)
 	if err = raftClusterPsCommand.Parse(args); err != nil {
-		return nil
+		return err
 	}
 
 	err = commandEnv.MasterClient.WithClient(context.Background(), false, func(client master_pb.SeaweedClient) error {

weed/shell/command_cluster_raft_remove.go

@@ -37,7 +37,7 @@ func (c *commandRaftServerRemove) Do(args []string, commandEnv *CommandEnv, writ
 	raftServerAddCommand := flag.NewFlagSet(c.Name(), flag.ContinueOnError)
 	serverId := raftServerAddCommand.String("id", "", "server id")
 	if err = raftServerAddCommand.Parse(args); err != nil {
-		return nil
+		return err
 	}
 
 	if *serverId == "" {

weed/shell/command_collection_delete.go

@@ -41,7 +41,7 @@ func (c *commandCollectionDelete) Do(args []string, commandEnv *CommandEnv, writ
 	applyBalancingAlias := colDeleteCommand.Bool("force", false, "apply the collection (alias for -apply)")
 
 	if err = colDeleteCommand.Parse(args); err != nil {
-		return nil
+		return err
 	}
 
 	handleDeprecatedForceFlag(writer, colDeleteCommand, applyBalancingAlias, applyBalancing)

weed/shell/command_ec_balance.go

@@ -55,7 +55,7 @@ func (c *commandEcBalance) Do(args []string, commandEnv *CommandEnv, writer io.W
 	applyBalancingAlias := balanceCommand.Bool("force", false, "apply the balancing plan (alias for -apply)")
 
 	if err = balanceCommand.Parse(args); err != nil {
-		return nil
+		return err
 	}
 
 	handleDeprecatedForceFlag(writer, balanceCommand, applyBalancingAlias, applyBalancing)

weed/shell/command_ec_decode.go

@@ -60,7 +60,7 @@ func (c *commandEcDecode) Do(args []string, commandEnv *CommandEnv, writer io.Wr
 	checkMinFreeSpace := decodeCommand.Bool("checkMinFreeSpace", true, "check min free space when selecting the decode target")
 	batchSize := decodeCommand.Int("batchSize", DefaultEcBatchSize, "decode up to this many volumes per topology refresh (0 = one snapshot for all volumes)")
 	if err = decodeCommand.Parse(args); err != nil {
-		return nil
+		return err
 	}
 	if *batchSize < 0 {
 		return fmt.Errorf("-batchSize must be >= 0")

weed/shell/command_ec_encode.go

@@ -114,7 +114,7 @@ func (c *commandEcEncode) Do(args []string, commandEnv *CommandEnv, writer io.Wr
 	verbose := encodeCommand.Bool("verbose", false, "show detailed reasons why volumes are not selected for encoding")
 
 	if err = encodeCommand.Parse(args); err != nil {
-		return nil
+		return err
 	}
 	if err = commandEnv.confirmIsLocked(args); err != nil {
 		return

weed/shell/command_ec_rebuild.go

@@ -88,7 +88,7 @@ func (c *commandEcRebuild) Do(args []string, commandEnv *CommandEnv, writer io.W
 	// TODO: remove this alias
 	applyChangesAlias := fixCommand.Bool("force", false, "apply the changes (alias for -apply)")
 	if err = fixCommand.Parse(args); err != nil {
-		return nil
+		return err
 	}
 	handleDeprecatedForceFlag(writer, fixCommand, applyChangesAlias, applyChanges)
 	infoAboutSimulationMode(writer, *applyChanges, "-apply")

weed/shell/command_flag_parse_test.go

@@ -0,0 +1,51 @@
+package shell
+
+import (
+	"bytes"
+	"flag"
+	"strings"
+	"testing"
+)
+
+// A command that parses flags must report a bad flag as an error. Returning
+// nil makes a typo in a weed shell script or a master maintenance script look
+// like a successful run that did nothing.
+func TestCommandsReturnFlagParseErrors(t *testing.T) {
+	for _, c := range Commands {
+		t.Run(c.Name(), func(t *testing.T) {
+			// fs.meta.load parses every argument but the last as flags.
+			err, needsEnv := doWithoutCommandEnv(c, []string{"-notAFlagOfAnyCommand", "arg"})
+			if needsEnv {
+				t.Skip("uses the command environment before parsing any flags")
+			}
+			if err == nil {
+				t.Fatal("an unknown flag was reported as success")
+			}
+			if !strings.Contains(err.Error(), "flag provided but not defined") {
+				t.Skipf("rejects its arguments without parsing flags: %v", err)
+			}
+		})
+	}
+}
+
+// doWithoutCommandEnv runs c with a nil CommandEnv. A command that panics here
+// used the environment before parsing flags, or takes no flags at all.
+func doWithoutCommandEnv(c command, args []string) (err error, needsEnv bool) {
+	defer func() {
+		if recover() != nil {
+			needsEnv = true
+		}
+	}()
+	var out bytes.Buffer
+	return c.Do(args, nil, &out), false
+}
+
+func TestProcessEachCmdTreatsHelpAsSuccess(t *testing.T) {
+	Commands = append(Commands, &fakeCommand{name: "test.help.command", err: flag.ErrHelp})
+	t.Cleanup(func() { Commands = Commands[:len(Commands)-1] })
+
+	exit, err := processEachCmd("test.help.command -h", nil)
+	if exit || err != nil {
+		t.Errorf("-h must not count as a failure, got exit=%v err=%v", exit, err)
+	}
+}

weed/shell/command_fs_configure.go

@@ -80,7 +80,7 @@ func (c *commandFsConfigure) Do(args []string, commandEnv *CommandEnv, writer io
 	isDelete := fsConfigureCommand.Bool("delete", false, "delete the configuration by locationPrefix")
 	apply := fsConfigureCommand.Bool("apply", false, "update and apply filer configuration")
 	if err = fsConfigureCommand.Parse(args); err != nil {
-		return nil
+		return err
 	}
 
 	fc, err := filer.ReadFilerConf(commandEnv.FilerAddress(), commandEnv.option.GrpcDialOption, commandEnv.MasterClient)

weed/shell/command_fs_meta_load.go

@@ -57,7 +57,7 @@ func (c *commandFsMetaLoad) Do(args []string, commandEnv *CommandEnv, writer io.
 	concurrency := metaLoadCommand.Int("concurrency", 1, "number of parallel meta load to filer")
 	verbose := metaLoadCommand.Bool("v", true, "verbose mode")
 	if err = metaLoadCommand.Parse(args[0 : len(args)-1]); err != nil {
-		return nil
+		return err
 	}
 
 	var dst io.Reader

weed/shell/command_mount_configure.go

@@ -45,7 +45,7 @@ func (c *commandMountConfigure) Do(args []string, commandEnv *CommandEnv, writer
 	mountDir := mountConfigureCommand.String("dir", "", "the mount directory same as how \"weed mount -dir=<mount_directory>\" was started")
 	mountQuota := mountConfigureCommand.Int("quotaMB", 0, "the quota in MB")
 	if err = mountConfigureCommand.Parse(args); err != nil {
-		return nil
+		return err
 	}
 
 	mountDirHash := util.HashToInt32([]byte(*mountDir))

weed/shell/command_remote_cache.go

@@ -74,7 +74,7 @@ func (c *commandRemoteCache) Do(args []string, commandEnv *CommandEnv, writer io
 	fileFiler := newFileFilter(remoteCacheCommand)
 
 	if err = remoteCacheCommand.Parse(args); err != nil {
-		return nil
+		return err
 	}
 
 	if *dir == "" {

weed/shell/command_remote_configure.go

@@ -69,7 +69,7 @@ func (c *commandRemoteConfigure) Do(args []string, commandEnv *CommandEnv, write
 
 	fs, isDelete, uploadConcurrency, downloadConcurrency := c.configureFlagSet(conf, false)
 	if err = fs.Parse(args); err != nil {
-		return nil
+		return err
 	}
 
 	if conf.Name == "" {
@@ -110,7 +110,7 @@ func (c *commandRemoteConfigure) Do(args []string, commandEnv *CommandEnv, write
 		}
 		fs, isDelete, uploadConcurrency, downloadConcurrency = c.configureFlagSet(conf, true)
 		if err = fs.Parse(args); err != nil {
-			return nil
+			return err
 		}
 	}
 

weed/shell/command_remote_meta_sync.go

@@ -67,7 +67,7 @@ func (c *commandRemoteMetaSync) Do(args []string, commandEnv *CommandEnv, writer
 	statFiles := remoteMetaSyncCommand.Bool("statFiles", false, "stat each new or changed file when the listing does not report all metadata (S3 listings lack Content-Encoding); costs one extra remote request per file")
 
 	if err = remoteMetaSyncCommand.Parse(args); err != nil {
-		return nil
+		return err
 	}
 
 	mappings, localMountedDir, remoteStorageMountedLocation, remoteStorageConf, detectErr := detectMountInfo(commandEnv, writer, *dir)

weed/shell/command_remote_mount.go

@@ -76,7 +76,7 @@ func (c *commandRemoteMount) Do(args []string, commandEnv *CommandEnv, writer io
 	cacheWait := remoteMountCommand.Duration("cacheWait", -1, "how long a read of an uncached object waits for the local cache, ex. 0 or 500ms (default: by object size)")
 
 	if err = remoteMountCommand.Parse(args); err != nil {
-		return nil
+		return err
 	}
 
 	if *dir == "" {

weed/shell/command_remote_mount_buckets.go

@@ -52,7 +52,7 @@ func (c *commandRemoteMountBuckets) Do(args []string, commandEnv *CommandEnv, wr
 	trimBucketSuffix := remoteMountBucketsCommand.Bool("trimBucketSuffix", true, "remote suffix auto generated by 'weed filer.remote.sync'")
 	apply := remoteMountBucketsCommand.Bool("apply", false, "apply the mount for listed buckets")
 	if err = remoteMountBucketsCommand.Parse(args); err != nil {
-		return nil
+		return err
 	}
 	infoAboutSimulationMode(writer, *apply, "-apply")
 

weed/shell/command_remote_uncache.go

@@ -55,7 +55,7 @@ func (c *commandRemoteUncache) Do(args []string, commandEnv *CommandEnv, writer
 	fileFiler := newFileFilter(remoteUncacheCommand)
 
 	if err = remoteUncacheCommand.Parse(args); err != nil {
-		return nil
+		return err
 	}
 
 	mappings, listErr := filer.ReadMountMappings(commandEnv.option.GrpcDialOption, commandEnv.FilerAddress())

weed/shell/command_remote_unmount.go

@@ -49,7 +49,7 @@ func (c *commandRemoteUnmount) Do(args []string, commandEnv *CommandEnv, writer
 	dir := remoteMountCommand.String("dir", "", "a directory in filer")
 
 	if err = remoteMountCommand.Parse(args); err != nil {
-		return nil
+		return err
 	}
 
 	mappings, listErr := filer.ReadMountMappings(commandEnv.option.GrpcDialOption, commandEnv.FilerAddress())

weed/shell/command_s3_bucket_delete.go

@@ -37,7 +37,7 @@ func (c *commandS3BucketDelete) Do(args []string, commandEnv *CommandEnv, writer
 	bucketCommand := flag.NewFlagSet(c.Name(), flag.ContinueOnError)
 	bucketName := bucketCommand.String("name", "", "bucket name")
 	if err = bucketCommand.Parse(args); err != nil {
-		return nil
+		return err
 	}
 
 	if *bucketName == "" {

weed/shell/command_s3_bucket_list.go

@@ -37,7 +37,7 @@ func (c *commandS3BucketList) Do(args []string, commandEnv *CommandEnv, writer i
 
 	bucketCommand := flag.NewFlagSet(c.Name(), flag.ContinueOnError)
 	if err = bucketCommand.Parse(args); err != nil {
-		return nil
+		return err
 	}
 
 	// collect collection information

weed/shell/command_s3_bucket_owner.go

@@ -56,7 +56,7 @@ func (c *commandS3BucketOwner) Do(args []string, commandEnv *CommandEnv, writer
 	bucketOwner := bucketCommand.String("owner", "", "new bucket owner identity name")
 	deleteOwner := bucketCommand.Bool("delete", false, "remove the bucket owner (make admin-only)")
 	if err = bucketCommand.Parse(args); err != nil {
-		return nil
+		return err
 	}
 
 	if *bucketName == "" {

weed/shell/command_s3_bucket_quota.go

@@ -43,7 +43,7 @@ func (c *commandS3BucketQuota) Do(args []string, commandEnv *CommandEnv, writer
 	operationName := bucketCommand.String("op", "set", "operation name [set|get|remove|enable|disable]")
 	sizeMB := bucketCommand.Int64("sizeMB", 0, "bucket quota size in MiB")
 	if err = bucketCommand.Parse(args); err != nil {
-		return nil
+		return err
 	}
 
 	if *bucketName == "" {

weed/shell/command_s3_bucket_quota_check.go

@@ -40,7 +40,7 @@ func (c *commandS3BucketQuotaEnforce) Do(args []string, commandEnv *CommandEnv,
 	bucketCommand := flag.NewFlagSet(c.Name(), flag.ContinueOnError)
 	applyQuotaLimit := bucketCommand.Bool("apply", false, "actually change the buckets readonly attribute")
 	if err = bucketCommand.Parse(args); err != nil {
-		return nil
+		return err
 	}
 	infoAboutSimulationMode(writer, *applyQuotaLimit, "-apply")
 

weed/shell/command_s3_circuitbreaker.go

@@ -75,7 +75,7 @@ func (c *commandS3CircuitBreaker) Do(args []string, commandEnv *CommandEnv, writ
 	apply := s3CircuitBreakerCommand.Bool("apply", false, "update and apply current configuration")
 
 	if err = s3CircuitBreakerCommand.Parse(args); err != nil {
-		return nil
+		return err
 
 	}
 

weed/shell/command_s3_clean_uploads.go

@@ -48,7 +48,7 @@ func (c *commandS3CleanUploads) Do(args []string, commandEnv *CommandEnv, writer
 	bucketCommand := flag.NewFlagSet(c.Name(), flag.ContinueOnError)
 	uploadedTimeAgo := bucketCommand.Duration("timeAgo", 24*time.Hour, "created time before now. \"1.5h\" or \"2h45m\". Valid time units are \"m\", \"h\"")
 	if err = bucketCommand.Parse(args); err != nil {
-		return nil
+		return err
 	}
 
 	var filerBucketsPath string

weed/shell/command_s3_configure.go

@@ -63,7 +63,7 @@ func (c *commandS3Configure) Do(args []string, commandEnv *CommandEnv, writer io
 	isDelete := s3ConfigureCommand.Bool("delete", false, "delete users, actions, access keys or policies")
 	apply := s3ConfigureCommand.Bool("apply", false, "update and apply s3 configuration")
 	if err = s3ConfigureCommand.Parse(args); err != nil {
-		return nil
+		return err
 	}
 
 	// Case 1: List configuration (no user specified)

weed/shell/command_volume_balance.go

@@ -158,7 +158,7 @@ func (c *commandVolumeBalance) Do(args []string, commandEnv *CommandEnv, writer
 		return fmt.Errorf("use \"ALL\", \"ACTIVE\" or \"FULL\"")
 	})
 	if err = balanceCommand.Parse(args); err != nil {
-		return nil
+		return err
 	}
 	handleDeprecatedForceFlag(writer, balanceCommand, applyBalancingAlias, applyBalancing)
 	c.applyBalancing = *applyBalancing

weed/shell/command_volume_check_disk.go

@@ -112,7 +112,7 @@ func (c *commandVolumeCheckDisk) Do(args []string, commandEnv *CommandEnv, write
 	nonRepairThreshold := fsckCommand.Float64("nonRepairThreshold", 0.3, "repair when missing keys is not more than this limit")
 	resurrectMissingNeedles := fsckCommand.Bool("resurrectMissingNeedles", false, "copy needles absent on one replica back from the other, only into never-vacuumed replicas (compaction revision 0)")
 	if err = fsckCommand.Parse(args); err != nil {
-		return nil
+		return err
 	}
 
 	handleDeprecatedForceFlag(writer, fsckCommand, applyChangesAlias, applyChanges)

weed/shell/command_volume_configure_replication.go

@@ -52,7 +52,7 @@ func (c *commandVolumeConfigureReplication) Do(args []string, commandEnv *Comman
 	collectionPattern := configureReplicationCommand.String("collectionPattern", "", "comma-separated collection names, with '*' and '?' wildcards; empty matches all")
 	maxParallelization := configureReplicationCommand.Int("maxParallelization", DefaultMaxParallelization, "run up to X tasks in parallel, whenever possible")
 	if err = configureReplicationCommand.Parse(args); err != nil {
-		return nil
+		return err
 	}
 
 	if err = commandEnv.confirmIsLocked(args); err != nil {

weed/shell/command_volume_copy.go

@@ -44,7 +44,7 @@ func (c *commandVolumeCopy) Do(args []string, commandEnv *CommandEnv, writer io.
 	targetNodeStr := volCopyCommand.String("target", "", "the target volume server <host>:<port>")
 	noLock := volCopyCommand.Bool("noLock", false, "do not lock the admin shell at one's own risk")
 	if err = volCopyCommand.Parse(args); err != nil {
-		return nil
+		return err
 	}
 
 	if *noLock {

weed/shell/command_volume_delete.go

@@ -43,7 +43,7 @@ func (c *commandVolumeDelete) Do(args []string, commandEnv *CommandEnv, writer i
 	nodeStr := volDeleteCommand.String("node", "", "the volume server <host>:<port>")
 	timeout := volDeleteCommand.Duration("timeout", 0, "wall-clock cap on the deletion; 0 = no timeout")
 	if err = volDeleteCommand.Parse(args); err != nil {
-		return nil
+		return err
 	}
 
 	if err = commandEnv.confirmIsLocked(args); err != nil {

weed/shell/command_volume_delete_empty.go

@@ -52,7 +52,7 @@ func (c *commandVolumeDeleteEmpty) Do(args []string, commandEnv *CommandEnv, wri
 	// TODO: remove this alias
 	applyBalancingAlias := volDeleteCommand.Bool("force", false, "apply to delete empty volumes (alias for -apply)")
 	if err = volDeleteCommand.Parse(args); err != nil {
-		return nil
+		return err
 	}
 
 	handleDeprecatedForceFlag(writer, volDeleteCommand, applyBalancingAlias, applyBalancing)

weed/shell/command_volume_fix_replication.go

@@ -84,7 +84,7 @@ func (c *commandVolumeFixReplication) Do(args []string, commandEnv *CommandEnv,
 	volumesPerStep := volFixReplicationCommand.Int("volumesPerStep", 0, "how many volumes to fix in one cycle")
 
 	if err = volFixReplicationCommand.Parse(args); err != nil {
-		return nil
+		return err
 	}
 
 	if c.collectionMatcher, err = wildcard.CompileCollectionMatcher(*collectionPattern); err != nil {

weed/shell/command_volume_fsck.go

@@ -141,7 +141,7 @@ func (c *commandVolumeFsck) Do(args []string, commandEnv *CommandEnv, writer io.
 	c.verifyNeedle = fsckCommand.Bool("verifyNeedles", false, "check needles status from volume server")
 
 	if err = fsckCommand.Parse(args); err != nil {
-		return nil
+		return err
 	}
 
 	// The command struct is a singleton registered in init(), so any state

weed/shell/command_volume_grow.go

@@ -46,7 +46,7 @@ func (c *commandGrow) Do(args []string, commandEnv *CommandEnv, writer io.Writer
 	diskType := volumeVacuumCommand.String("diskType", "", "grow volumes only from the specified disk type")
 
 	if err = volumeVacuumCommand.Parse(args); err != nil {
-		return nil
+		return err
 	}
 	if *collection == "" {
 		return fmt.Errorf("collection option is required")

weed/shell/command_volume_list.go

@@ -63,7 +63,7 @@ func (c *commandVolumeList) Do(args []string, commandEnv *CommandEnv, writer io.
 	c.dataNode = volumeListCommand.String("dataNode", "", "show volumes only from the specified data node")
 
 	if err = volumeListCommand.Parse(args); err != nil {
-		return nil
+		return err
 	}
 
 	if c.collectionMatcher, err = wildcard.CompileCollectionMatcher(*collectionPattern); err != nil {

weed/shell/command_volume_mark.go

@@ -53,7 +53,7 @@ func (c *commandVolumeMark) Do(args []string, commandEnv *CommandEnv, writer io.
 	readonly := volMarkCommand.Bool("readonly", false, "volume mark readonly")
 	readonlyCanDelete := volMarkCommand.Bool("readonlyCanDelete", false, "volume mark readonly but still accepting deletes")
 	if err = volMarkCommand.Parse(args); err != nil {
-		return nil
+		return err
 	}
 	collectionSet, nodeSet, volumeIdSet := false, false, false
 	volMarkCommand.Visit(func(f *flag.Flag) {

weed/shell/command_volume_mount.go

@@ -43,7 +43,7 @@ func (c *commandVolumeMount) Do(args []string, commandEnv *CommandEnv, writer io
 	volumeIdInt := volMountCommand.Int("volumeId", 0, "the volume id")
 	nodeStr := volMountCommand.String("node", "", "the volume server <host>:<port>")
 	if err = volMountCommand.Parse(args); err != nil {
-		return nil
+		return err
 	}
 
 	if err = commandEnv.confirmIsLocked(args); err != nil {

weed/shell/command_volume_move.go

@@ -64,7 +64,7 @@ func (c *commandVolumeMove) Do(args []string, commandEnv *CommandEnv, writer io.
 	noLock := volMoveCommand.Bool("noLock", false, "do not lock the admin shell at one's own risk")
 
 	if err = volMoveCommand.Parse(args); err != nil {
-		return nil
+		return err
 	}
 
 	if *noLock {

weed/shell/command_volume_server_leave.go

@@ -48,7 +48,7 @@ func (c *commandVolumeServerLeave) Do(args []string, commandEnv *CommandEnv, wri
 	// TODO: remove this alias
 	applyChangesAlias := vsLeaveCommand.Bool("force", false, "apply the changes (alias for -apply)")
 	if err = vsLeaveCommand.Parse(args); err != nil {
-		return nil
+		return err
 	}
 
 	handleDeprecatedForceFlag(writer, vsLeaveCommand, applyChangesAlias, applyChanges)

weed/shell/command_volume_tier_compact.go

@@ -68,7 +68,7 @@ func (c *commandVolumeTierCompact) Do(args []string, commandEnv *CommandEnv, wri
 	garbageThreshold := tierCommand.Float64("garbageThreshold", 0.3, "compact when garbage ratio exceeds this value")
 	concurrency := tierCommand.Int("concurrency", 0, "multipart transfer concurrency (0 = backend default)")
 	if err = tierCommand.Parse(args); err != nil {
-		return nil
+		return err
 	}
 
 	if err = validateTierConcurrency(*concurrency); err != nil {

weed/shell/command_volume_tier_download.go

@@ -66,7 +66,7 @@ func (c *commandVolumeTierDownload) Do(args []string, commandEnv *CommandEnv, wr
 	collection := tierCommand.String("collection", "", "comma-separated collection names, wildcards, or regex patterns; empty matches the collection with no name")
 	concurrency := tierCommand.Int("concurrency", 0, "multipart download concurrency (0 = backend default)")
 	if err = tierCommand.Parse(args); err != nil {
-		return nil
+		return err
 	}
 
 	if err = validateTierConcurrency(*concurrency); err != nil {

weed/shell/command_volume_tier_move.go

@@ -95,7 +95,7 @@ func (c *commandVolumeTierMove) Do(args []string, commandEnv *CommandEnv, writer
 	replicationString := tierCommand.String("toReplication", "", "the new target replication setting")
 
 	if err = tierCommand.Parse(args); err != nil {
-		return nil
+		return err
 	}
 
 	handleDeprecatedForceFlag(writer, tierCommand, applyChangeAlias, applyChange)

weed/shell/command_volume_tier_upload.go

@@ -97,7 +97,7 @@ func (c *commandVolumeTierUpload) Do(args []string, commandEnv *CommandEnv, writ
 	disk := tierCommand.String("disk", "", "[hdd|ssd|<tag>] hard drive or solid state drive or any tag")
 	concurrency := tierCommand.Int("concurrency", 0, "multipart upload concurrency (0 = backend default)")
 	if err = tierCommand.Parse(args); err != nil {
-		return nil
+		return err
 	}
 
 	if err = validateTierConcurrency(*concurrency); err != nil {

weed/shell/command_volume_unmount.go

@@ -44,7 +44,7 @@ func (c *commandVolumeUnmount) Do(args []string, commandEnv *CommandEnv, writer
 	volumeIdInt := volUnmountCommand.Int("volumeId", 0, "the volume id")
 	nodeStr := volUnmountCommand.String("node", "", "the volume server <host>:<port>")
 	if err = volUnmountCommand.Parse(args); err != nil {
-		return nil
+		return err
 	}
 	if *nodeStr == "" {
 		return fmt.Errorf("-node option is required")

weed/shell/command_volume_vacuum.go

@@ -52,7 +52,7 @@ func (c *commandVacuum) Do(args []string, commandEnv *CommandEnv, writer io.Writ
 	collection := volumeVacuumCommand.String("collection", "", "comma-separated collection names, wildcards, or regex patterns; empty or \"*\" matches all, \""+CollectionDefault+"\" the collection with no name")
 	volumeIds := volumeVacuumCommand.String("volumeId", "", "comma-separated list of volume IDs")
 	if err = volumeVacuumCommand.Parse(args); err != nil {
-		return nil
+		return err
 	}
 
 	collectionMatcher, err := wildcard.CompileCollectionMatcher(*collection)

weed/shell/shell_liner.go

@@ -137,7 +137,7 @@ func processEachCmd(cmd string, commandEnv *CommandEnv) (exit bool, cmdErr error
 					// every later command in the session unlocked, so a real
 					// mutation right after a simulation would skip its lock.
 					commandEnv.SetNoLock(false)
-					if err := c.Do(args, commandEnv, os.Stdout); err != nil {
+					if err := c.Do(args, commandEnv, os.Stdout); err != nil && !isHelpError(err) {
 						fmt.Fprintf(os.Stderr, "error: %v\n", err)
 						cmdErr = err
 					}