cli: added standard --json flags to several commands (#910)

* cli: added standard --json flags to several commands

Fixes #272

* Update flag description

Co-authored-by: Julio López <julio+gh@kasten.io>

cli/command_acl_list.go

@@ -7,23 +7,39 @@
 
 	"github.com/kopia/kopia/internal/acl"
 	"github.com/kopia/kopia/repo"
+	"github.com/kopia/kopia/repo/manifest"
 )
 
 var aclListCommand = aclCommands.Command("list", "List ACL entries").Alias("ls")
 
 func runACLList(ctx context.Context, rep repo.Repository) error {
+	var jl jsonList
+
+	jl.begin()
+	defer jl.end()
+
 	entries, err := acl.LoadEntries(ctx, rep, nil)
 	if err != nil {
 		return errors.Wrap(err, "error loading ACL entries")
 	}
 
 	for _, e := range entries {
-		printStdout("id:%v user:%v access:%v target:%v\n", e.ManifestID, e.User, e.Access, e.Target)
+		if jsonOutput {
+			jl.emit(aclListItem{e.ManifestID, e})
+		} else {
+			printStdout("id:%v user:%v access:%v target:%v\n", e.ManifestID, e.User, e.Access, e.Target)
+		}
 	}
 
 	return nil
 }
 
+type aclListItem struct {
+	ID manifest.ID `json:"id"`
+	*acl.Entry
+}
+
 func init() {
+	registerJSONOutputFlags(aclListCommand)
 	aclListCommand.Action(repositoryReaderAction(runACLList))
 }

cli/command_blob_list.go

@@ -16,6 +16,11 @@
 )
 
 func runBlobList(ctx context.Context, rep repo.DirectRepository) error {
+	var jl jsonList
+
+	jl.begin()
+	defer jl.end()
+
 	return rep.BlobReader().ListBlobs(ctx, blob.ID(*blobListPrefix), func(b blob.Metadata) error {
 		if *blobListMaxSize != 0 && b.Length > *blobListMaxSize {
 			return nil
@@ -25,11 +30,16 @@ func runBlobList(ctx context.Context, rep repo.DirectRepository) error {
 			return nil
 		}
 
-		fmt.Printf("%-70v %10v %v\n", b.BlobID, b.Length, formatTimestamp(b.Timestamp))
+		if jsonOutput {
+			jl.emit(b)
+		} else {
+			fmt.Printf("%-70v %10v %v\n", b.BlobID, b.Length, formatTimestamp(b.Timestamp))
+		}
 		return nil
 	})
 }
 
 func init() {
+	registerJSONOutputFlags(blobListCommand)
 	blobListCommand.Action(directRepositoryReadAction(runBlobList))
 }

cli/command_content_list.go

@@ -21,6 +21,11 @@
 )
 
 func runContentListCommand(ctx context.Context, rep repo.DirectRepository) error {
+	var jl jsonList
+
+	jl.begin()
+	defer jl.end()
+
 	var totalSize stats.CountSum
 
 	err := rep.ContentReader().IterateContents(
@@ -36,6 +41,11 @@ func(b content.Info) error {
 
 			totalSize.Add(int64(b.Length))
 
+			if jsonOutput {
+				jl.emit(b)
+				return nil
+			}
+
 			if *contentListLong {
 				optionalDeleted := ""
 				if b.Deleted {
@@ -69,6 +79,7 @@ func(b content.Info) error {
 }
 
 func init() {
+	registerJSONOutputFlags(contentListCommand)
 	contentListCommand.Action(directRepositoryReadAction(runContentListCommand))
 	setupContentIDRangeFlags(contentListCommand)
 }

cli/command_index_list.go

@@ -18,6 +18,11 @@
 )
 
 func runListBlockIndexesAction(ctx context.Context, rep repo.DirectRepository) error {
+	var jl jsonList
+
+	jl.begin()
+	defer jl.end()
+
 	blks, err := rep.IndexBlobReader().IndexBlobs(ctx, *blockIndexListIncludeSuperseded)
 	if err != nil {
 		return errors.Wrap(err, "error listing index blobs")
@@ -39,10 +44,14 @@ func runListBlockIndexesAction(ctx context.Context, rep repo.DirectRepository) e
 	}
 
 	for _, b := range blks {
-		fmt.Printf("%-40v %10v %v %v\n", b.BlobID, b.Length, formatTimestampPrecise(b.Timestamp), b.Superseded)
+		if jsonOutput {
+			jl.emit(b)
+		} else {
+			fmt.Printf("%-40v %10v %v %v\n", b.BlobID, b.Length, formatTimestampPrecise(b.Timestamp), b.Superseded)
+		}
 	}
 
-	if *blockIndexListSummary {
+	if *blockIndexListSummary && !jsonOutput {
 		fmt.Printf("total %v indexes\n", len(blks))
 	}
 
@@ -50,5 +59,6 @@ func runListBlockIndexesAction(ctx context.Context, rep repo.DirectRepository) e
 }
 
 func init() {
+	registerJSONOutputFlags(blockIndexListCommand)
 	blockIndexListCommand.Action(directRepositoryReadAction(runListBlockIndexesAction))
 }

cli/command_maintenance_info.go

@@ -2,8 +2,6 @@
 
 import (
 	"context"
-	"encoding/json"
-	"os"
 	"time"
 
 	"github.com/pkg/errors"
@@ -13,10 +11,7 @@
 	"github.com/kopia/kopia/repo/maintenance"
 )
 
-var (
-	maintenanceInfoCommand = maintenanceCommands.Command("info", "Display maintenance information").Alias("status")
-	maintenanceInfoJSON    = maintenanceInfoCommand.Flag("json", "Show raw JSON data").Short('j').Bool()
-)
+var maintenanceInfoCommand = maintenanceCommands.Command("info", "Display maintenance information").Alias("status")
 
 func runMaintenanceInfoCommand(ctx context.Context, rep repo.DirectRepository) error {
 	p, err := maintenance.GetParams(ctx, rep)
@@ -29,11 +24,8 @@ func runMaintenanceInfoCommand(ctx context.Context, rep repo.DirectRepository) e
 		return errors.Wrap(err, "unable to get maintenance schedule")
 	}
 
-	if *maintenanceInfoJSON {
-		e := json.NewEncoder(os.Stdout)
-		e.SetIndent("", "  ")
-		e.Encode(s) //nolint:errcheck
-
+	if jsonOutput {
+		printStdout("%s\n", jsonBytes(s))
 		return nil
 	}
 
@@ -83,5 +75,6 @@ func displayCycleInfo(c *maintenance.CycleParams, t time.Time, rep repo.DirectRe
 }
 
 func init() {
+	registerJSONOutputFlags(maintenanceInfoCommand)
 	maintenanceInfoCommand.Action(directRepositoryReadAction(runMaintenanceInfoCommand))
 }

cli/command_manifest_ls.go

@@ -18,10 +18,16 @@
 )
 
 func init() {
+	registerJSONOutputFlags(manifestListCommand)
 	manifestListCommand.Action(repositoryReaderAction(listManifestItems))
 }
 
 func listManifestItems(ctx context.Context, rep repo.Repository) error {
+	var jl jsonList
+
+	jl.begin()
+	defer jl.end()
+
 	filter := map[string]string{}
 
 	for _, kv := range *manifestListFilter {
@@ -49,8 +55,12 @@ func listManifestItems(ctx context.Context, rep repo.Repository) error {
 	})
 
 	for _, it := range items {
-		t := it.Labels["type"]
-		fmt.Printf("%v %10v %v type:%v %v\n", it.ID, it.Length, formatTimestamp(it.ModTime.Local()), t, sortedMapValues(it.Labels))
+		if jsonOutput {
+			jl.emit(it)
+		} else {
+			t := it.Labels["type"]
+			fmt.Printf("%v %10v %v type:%v %v\n", it.ID, it.Length, formatTimestamp(it.ModTime.Local()), t, sortedMapValues(it.Labels))
+		}
 	}
 
 	return nil

cli/command_policy_ls.go

@@ -14,10 +14,16 @@
 var policyListCommand = policyCommands.Command("list", "List policies.").Alias("ls")
 
 func init() {
+	registerJSONOutputFlags(policyListCommand)
 	policyListCommand.Action(repositoryReaderAction(listPolicies))
 }
 
 func listPolicies(ctx context.Context, rep repo.Repository) error {
+	var jl jsonList
+
+	jl.begin()
+	defer jl.end()
+
 	policies, err := policy.ListPolicies(ctx, rep)
 	if err != nil {
 		return errors.Wrap(err, "error listing policies")
@@ -28,7 +34,11 @@ func listPolicies(ctx context.Context, rep repo.Repository) error {
 	})
 
 	for _, pol := range policies {
-		fmt.Println(pol.ID(), pol.Target())
+		if jsonOutput {
+			jl.emit(policy.TargetWithPolicy{ID: pol.ID(), Target: pol.Target(), Policy: pol})
+		} else {
+			fmt.Println(pol.ID(), pol.Target())
+		}
 	}
 
 	return nil

cli/command_policy_show.go

@@ -17,10 +17,10 @@
 	policyShowCommand = policyCommands.Command("show", "Show snapshot policy.").Alias("get")
 	policyShowGlobal  = policyShowCommand.Flag("global", "Get global policy").Bool()
 	policyShowTargets = policyShowCommand.Arg("target", "Target to show the policy for").Strings()
-	policyShowJSON    = policyShowCommand.Flag("json", "Show JSON").Short('j').Bool()
 )
 
 func init() {
+	registerJSONOutputFlags(policyShowCommand)
 	policyShowCommand.Action(repositoryReaderAction(showPolicy))
 }
 
@@ -36,8 +36,8 @@ func showPolicy(ctx context.Context, rep repo.Repository) error {
 			return errors.Wrapf(err, "can't get effective policy for %q", target)
 		}
 
-		if *policyShowJSON {
-			fmt.Println(effective)
+		if jsonOutput {
+			printStdout("%s\n", jsonBytes(effective))
 		} else {
 			printPolicy(effective, policies)
 		}

cli/command_snapshot_create.go

@@ -262,6 +262,11 @@ func reportSnapshotStatus(ctx context.Context, manifest *snapshot.Manifest) erro
 
 	snapID := manifest.ID
 
+	if jsonOutput {
+		printStdout("%s\n", jsonIndentedBytes(manifest, "  "))
+		return nil
+	}
+
 	log(ctx).Infof("Created%v snapshot with root %v and ID %v in %v", maybePartial, manifest.RootObjectID(), snapID, manifest.EndTime.Sub(manifest.StartTime).Truncate(time.Second))
 
 	if ds := manifest.RootEntry.DirSummary; ds != nil {
@@ -359,5 +364,6 @@ func shouldSnapshotSource(ctx context.Context, src snapshot.SourceInfo, rep repo
 }
 
 func init() {
+	registerJSONOutputFlags(snapshotCreateCommand)
 	snapshotCreateCommand.Action(repositoryWriterAction(runSnapshotCommand))
 }

cli/command_snapshot_list.go

@@ -85,6 +85,11 @@ func findManifestIDs(ctx context.Context, rep repo.Repository, source string) ([
 }
 
 func runSnapshotsCommand(ctx context.Context, rep repo.Repository) error {
+	var jl jsonList
+
+	jl.begin()
+	defer jl.end()
+
 	manifestIDs, relPath, err := findManifestIDs(ctx, rep, *snapshotListPath)
 	if err != nil {
 		return err
@@ -95,6 +100,16 @@ func runSnapshotsCommand(ctx context.Context, rep repo.Repository) error {
 		return errors.Wrap(err, "unable to load snapshots")
 	}
 
+	if jsonOutput {
+		for _, snapshotGroup := range snapshot.GroupBySource(manifests) {
+			for _, m := range snapshotGroup {
+				jl.emit(m)
+			}
+		}
+
+		return nil
+	}
+
 	return outputManifestGroups(ctx, rep, manifests, strings.Split(relPath, "/"))
 }
 
@@ -282,5 +297,6 @@ func deltaBytes(b int64) string {
 }
 
 func init() {
+	registerJSONOutputFlags(snapshotListCommand)
 	snapshotListCommand.Action(repositoryReaderAction(runSnapshotsCommand))
 }

cli/command_user_list.go

@@ -12,18 +12,28 @@
 var userListCommand = userCommands.Command("list", "List users").Alias("ls")
 
 func runUserList(ctx context.Context, rep repo.Repository) error {
+	var jl jsonList
+
+	jl.begin()
+	defer jl.end()
+
 	profiles, err := user.ListUserProfiles(ctx, rep)
 	if err != nil {
 		return errors.Wrap(err, "error listing user profiles")
 	}
 
 	for _, p := range profiles {
-		printStdout("%v\n", p.Username)
+		if jsonOutput {
+			jl.emit(p)
+		} else {
+			printStdout("%v\n", p.Username)
+		}
 	}
 
 	return nil
 }
 
 func init() {
+	registerJSONOutputFlags(userListCommand)
 	userListCommand.Action(repositoryReaderAction(runUserList))
 }

cli/json_output.go

@@ -0,0 +1,117 @@
+package cli
+
+import (
+	"encoding/json"
+
+	"github.com/alecthomas/kingpin"
+
+	"github.com/kopia/kopia/snapshot"
+)
+
+var (
+	jsonOutput  = false
+	jsonIndent  = false
+	jsonVerbose = false // output addnon-essential stats as part of JSON
+)
+
+func registerJSONOutputFlags(cmd *kingpin.CmdClause) {
+	cmd.Flag("json", "Output result in JSON format to stdout").BoolVar(&jsonOutput)
+	cmd.Flag("json-indent", "Output result in indented JSON format to stdout").Hidden().BoolVar(&jsonIndent)
+	cmd.Flag("json-verbose", "Output non-essential data (e.g. statistics) in JSON format").Hidden().BoolVar(&jsonVerbose)
+}
+
+func cleanupSnapshotManifestForJSON(v *snapshot.Manifest) interface{} {
+	m := *v
+
+	if !jsonVerbose {
+		return struct {
+			*snapshot.Manifest
+
+			// trick to remove 'stats' completely.
+			Stats string `json:"stats,omitempty"`
+		}{Manifest: v}
+	}
+
+	return &m
+}
+
+func cleanupSnapshotManifestListForJSON(manifests []*snapshot.Manifest) interface{} {
+	var res []interface{}
+
+	for _, m := range manifests {
+		res = append(res, cleanupSnapshotManifestForJSON(m))
+	}
+
+	return res
+}
+
+func cleanupForJSON(v interface{}) interface{} {
+	switch v := v.(type) {
+	case *snapshot.Manifest:
+		return cleanupSnapshotManifestForJSON(v)
+	case []*snapshot.Manifest:
+		return cleanupSnapshotManifestListForJSON(v)
+	default:
+		return v
+	}
+}
+
+func jsonBytes(v interface{}) []byte {
+	return jsonIndentedBytes(v, "")
+}
+
+func jsonIndentedBytes(v interface{}, indent string) []byte {
+	v = cleanupForJSON(v)
+
+	var (
+		b   []byte
+		err error
+	)
+
+	if jsonIndent {
+		b, err = json.MarshalIndent(v, indent+"", indent+"  ")
+	} else {
+		b, err = json.Marshal(v)
+	}
+
+	if err != nil {
+		panic("error serializing JSON, that should not happen: " + err.Error())
+	}
+
+	return b
+}
+
+type jsonList struct {
+	separator string
+}
+
+func (l *jsonList) begin() {
+	if jsonOutput {
+		printStdout("[")
+
+		if !jsonIndent {
+			l.separator = "\n "
+		}
+	}
+}
+
+func (l *jsonList) end() {
+	if jsonOutput {
+		if !jsonIndent {
+			printStdout("\n")
+		}
+
+		printStdout("]")
+	}
+}
+
+func (l *jsonList) emit(v interface{}) {
+	printStdout(l.separator)
+	printStdout("%s", jsonBytes(v))
+
+	if jsonIndent {
+		l.separator = ","
+	} else {
+		l.separator = ",\n "
+	}
+}

fs/entry.go

@@ -23,14 +23,14 @@ type Entry interface {
 
 // OwnerInfo describes owner of a filesystem entry.
 type OwnerInfo struct {
-	UserID  uint32
-	GroupID uint32
+	UserID  uint32 `json:"uid"`
+	GroupID uint32 `json:"gid"`
 }
 
 // DeviceInfo describes the device this filesystem entry is on.
 type DeviceInfo struct {
-	Dev  uint64
-	Rdev uint64
+	Dev  uint64 `json:"dev"`
+	Rdev uint64 `json:"rdev"`
 }
 
 // Entries is a list of entries sorted by name.

snapshot/manifest.go

@@ -22,7 +22,7 @@ type Manifest struct {
 	StartTime   time.Time `json:"startTime"`
 	EndTime     time.Time `json:"endTime"`
 
-	Stats            Stats  `json:"stats"`
+	Stats            Stats  `json:"stats,omitempty"`
 	IncompleteReason string `json:"incomplete,omitempty"`
 
 	RootEntry *DirEntry `json:"rootEntry"`

snapshot/policy/policy.go

@@ -11,6 +11,13 @@
 // ErrPolicyNotFound is returned when the policy is not found.
 var ErrPolicyNotFound = errors.New("policy not found")
 
+// TargetWithPolicy wraps a policy with its target and ID.
+type TargetWithPolicy struct {
+	ID     string              `json:"id"`
+	Target snapshot.SourceInfo `json:"target"`
+	*Policy
+}
+
 // Policy describes snapshot policy for a single source.
 type Policy struct {
 	Labels              map[string]string   `json:"-"`

tests/end_to_end_test/api_server_repository_test.go

@@ -12,6 +12,7 @@
 	"github.com/kopia/kopia/internal/serverapi"
 	"github.com/kopia/kopia/internal/testlogging"
 	"github.com/kopia/kopia/repo"
+	"github.com/kopia/kopia/repo/blob"
 	"github.com/kopia/kopia/tests/testenv"
 )
 
@@ -65,8 +66,13 @@ func testAPIServerRepository(t *testing.T, serverStartArgs []string, useGRPC, al
 	e1.RunAndExpectSuccess(t, "repo", "connect", "filesystem", "--path", e.RepoDir, "--override-username", "not-foo", "--override-hostname", "bar")
 	e1.RunAndExpectSuccess(t, "snapshot", "create", sharedTestDataDir1)
 
-	originalPBlobCount := len(e1.RunAndExpectSuccess(t, "blob", "list", "--prefix=p"))
-	originalQBlobCount := len(e1.RunAndExpectSuccess(t, "blob", "list", "--prefix=q"))
+	var pBlobsBefore, qBlobsBefore []blob.Metadata
+
+	mustParseJSONLines(t, e1.RunAndExpectSuccess(t, "blob", "list", "--prefix=p", "--json"), &pBlobsBefore)
+	mustParseJSONLines(t, e1.RunAndExpectSuccess(t, "blob", "list", "--prefix=q", "--json"), &qBlobsBefore)
+
+	originalPBlobCount := len(pBlobsBefore)
+	originalQBlobCount := len(qBlobsBefore)
 
 	tlsCert := filepath.Join(e.ConfigDir, "tls.cert")
 	tlsKey := filepath.Join(e.ConfigDir, "tls.key")

tests/end_to_end_test/policy_test.go

@@ -3,6 +3,9 @@
 import (
 	"testing"
 
+	"github.com/kopia/kopia/repo/content"
+	"github.com/kopia/kopia/repo/manifest"
+	"github.com/kopia/kopia/snapshot/policy"
 	"github.com/kopia/kopia/tests/testenv"
 )
 
@@ -17,12 +20,33 @@ func TestDefaultGlobalPolicy(t *testing.T) {
 	e.RunAndExpectSuccess(t, "policy", "show", "--global")
 
 	// verify we created global policy entry
-	globalPolicyBlockID := e.RunAndVerifyOutputLineCount(t, 1, "content", "ls")[0]
-	e.RunAndExpectSuccess(t, "content", "show", "-jz", globalPolicyBlockID)
+
+	var contents []content.Info
+
+	mustParseJSONLines(t, e.RunAndExpectSuccess(t, "content", "ls", "--json"), &contents)
+
+	if got, want := len(contents), 1; got != want {
+		t.Fatalf("unexpected number of contents %v, want %v", got, want)
+	}
+
+	globalPolicyContentID := contents[0].ID
+	e.RunAndExpectSuccess(t, "content", "show", "-jz", string(globalPolicyContentID))
 
 	// make sure the policy is visible in the manifest list
-	e.RunAndVerifyOutputLineCount(t, 1, "manifest", "list", "--filter=type:policy", "--filter=policyType:global")
+	var manifests []manifest.EntryMetadata
+
+	mustParseJSONLines(t, e.RunAndExpectSuccess(t, "manifest", "list", "--filter=type:policy", "--filter=policyType:global", "--json"), &manifests)
+
+	if got, want := len(manifests), 1; got != want {
+		t.Fatalf("unexpected number of manifests %v, want %v", got, want)
+	}
 
 	// make sure the policy is visible in the policy list
-	e.RunAndVerifyOutputLineCount(t, 1, "policy", "list")
+	var plist []policy.TargetWithPolicy
+
+	mustParseJSONLines(t, e.RunAndExpectSuccess(t, "policy", "list", "--json"), &plist)
+
+	if got, want := len(plist), 1; got != want {
+		t.Fatalf("unexpected number of policies %v, want %v", got, want)
+	}
 }

tests/end_to_end_test/snapshot_create_test.go

@@ -1,6 +1,7 @@
 package endtoend_test
 
 import (
+	"encoding/json"
 	"os"
 	"path"
 	"path/filepath"
@@ -15,6 +16,7 @@
 
 	"github.com/kopia/kopia/internal/testutil"
 	"github.com/kopia/kopia/repo"
+	"github.com/kopia/kopia/snapshot"
 	"github.com/kopia/kopia/tests/testenv"
 )
 
@@ -39,8 +41,26 @@ func TestSnapshotCreate(t *testing.T) {
 	e.RunAndExpectSuccess(t, "snapshot", "create", sharedTestDataDir1)
 	e.RunAndExpectSuccess(t, "snapshot", "create", sharedTestDataDir1)
 
-	e.RunAndExpectSuccess(t, "snapshot", "create", sharedTestDataDir2)
-	e.RunAndExpectSuccess(t, "snapshot", "create", sharedTestDataDir2)
+	var man1, man2 snapshot.Manifest
+
+	mustParseJSONLines(t, e.RunAndExpectSuccess(t, "snapshot", "create", sharedTestDataDir2, "--json"), &man1)
+	mustParseJSONLines(t, e.RunAndExpectSuccess(t, "snapshot", "create", sharedTestDataDir2, "--json"), &man2)
+
+	if man1.RootEntry.ObjectID == "" {
+		t.Fatalf("missing root id")
+	}
+
+	if man1.RootEntry.ObjectID != man2.RootEntry.ObjectID {
+		t.Fatalf("unexpected difference in root objects %v vs %v", man1.RootEntry.ObjectID, man2.RootEntry.ObjectID)
+	}
+
+	var manifests []snapshot.Manifest
+
+	mustParseJSONLines(t, e.RunAndExpectSuccess(t, "snapshot", "list", "-a", "--json"), &manifests)
+
+	if got, want := len(manifests), 6; got != want {
+		t.Fatalf("unexpected number of snapshots %v want %v", got, want)
+	}
 
 	sources := e.ListSnapshotsAndExpectSuccess(t)
 	// will only list snapshots we created, not foo@foo
@@ -590,3 +610,15 @@ func createFileStructure(baseDir string, files []testFileEntry) error {
 
 	return nil
 }
+
+func mustParseJSONLines(t *testing.T, lines []string, v interface{}) {
+	t.Helper()
+
+	allJSON := strings.Join(lines, "\n")
+	dec := json.NewDecoder(strings.NewReader(allJSON))
+	dec.DisallowUnknownFields()
+
+	if err := dec.Decode(v); err != nil {
+		t.Fatalf("failed to parse JSON %v: %v", allJSON, err)
+	}
+}

tests/end_to_end_test/snapshot_gc_test.go

@@ -9,6 +9,7 @@
 	"time"
 
 	"github.com/kopia/kopia/internal/testutil"
+	"github.com/kopia/kopia/repo/content"
 	"github.com/kopia/kopia/tests/testenv"
 )
 
@@ -55,7 +56,13 @@ func TestSnapshotGC(t *testing.T) {
 	e.RunAndExpectSuccess(t, "snapshot", "gc")
 
 	// data block + directory block + manifest block + manifest block from manifest deletion
-	e.RunAndVerifyOutputLineCount(t, expectedContentCount, "content", "list")
+	var contentInfo []content.Info
+
+	mustParseJSONLines(t, e.RunAndExpectSuccess(t, "content", "list", "--json"), &contentInfo)
+
+	if got, want := len(contentInfo), expectedContentCount; got != want {
+		t.Fatalf("unexpected number of contents: %v, want %v", got, want)
+	}
 
 	// garbage-collect for real, but contents are too recent so won't be deleted
 	e.RunAndExpectSuccess(t, "snapshot", "gc", "--delete")