Merge 4e17d8cfb7 into 228b35f074

cmd/restic/cmd_forget.go

@@ -3,6 +3,7 @@ package main
 import (
 	"context"
 	"encoding/json"
+	"fmt"
 	"io"
 	"strconv"
 
@@ -88,6 +89,8 @@ type ForgetOptions struct {
 	WithinYearly  restic.Duration
 	KeepTags      restic.TagLists
 
+	UnsafeAllowRemoveAll bool
+
 	restic.SnapshotFilter
 	Compact bool
 
@@ -117,6 +120,7 @@ func init() {
 	f.VarP(&forgetOptions.WithinMonthly, "keep-within-monthly", "", "keep monthly snapshots that are newer than `duration` (eg. 1y5m7d2h) relative to the latest snapshot")
 	f.VarP(&forgetOptions.WithinYearly, "keep-within-yearly", "", "keep yearly snapshots that are newer than `duration` (eg. 1y5m7d2h) relative to the latest snapshot")
 	f.Var(&forgetOptions.KeepTags, "keep-tag", "keep snapshots with this `taglist` (can be specified multiple times)")
+	f.BoolVar(&forgetOptions.UnsafeAllowRemoveAll, "unsafe-allow-remove-all", false, "allow deleting all snapshots of a snapshot group")
 
 	initMultiSnapshotFilter(f, &forgetOptions.SnapshotFilter, false)
 	f.StringArrayVar(&forgetOptions.Hosts, "hostname", nil, "only consider snapshots with the given `hostname` (can be specified multiple times)")
@@ -209,13 +213,17 @@ func runForget(ctx context.Context, opts ForgetOptions, pruneOptions PruneOption
 			Tags:          opts.KeepTags,
 		}
 
-		if policy.Empty() && len(args) == 0 {
+		if policy.Empty() {
-			if !gopts.JSON {
+			if opts.UnsafeAllowRemoveAll {
-				Verbosef("no policy was specified, no snapshots will be removed\n")
+				if opts.SnapshotFilter.Empty() {
+					return errors.Fatal("--unsafe-allow-remove-all is not allowed unless a snapshot filter option is specified")
+				}
+				// UnsafeAllowRemoveAll together with snapshot filter is fine
+			} else {
+				return errors.Fatal("no policy was specified, no snapshots will be removed")
 			}
 		}
 
-		if !policy.Empty() {
 		if !gopts.JSON {
 			Verbosef("Applying Policy: %v\n", policy)
 		}
@@ -240,6 +248,10 @@ func runForget(ctx context.Context, opts ForgetOptions, pruneOptions PruneOption
 
 			keep, remove, reasons := restic.ApplyPolicy(snapshotGroup, policy)
 
+			if !policy.Empty() && len(keep) == 0 {
+				return fmt.Errorf("refusing to delete last snapshot of snapshot group %v", key)
+			}
+
 			if len(keep) != 0 && !gopts.Quiet && !gopts.JSON {
 				Printf("keep %d snapshots:\n", len(keep))
 				PrintSnapshots(globalOptions.stdout, keep, reasons, opts.Compact)
@@ -263,7 +275,6 @@ func runForget(ctx context.Context, opts ForgetOptions, pruneOptions PruneOption
 			}
 		}
 	}
-	}
 
 	if len(removeSnIDs) > 0 {
 		if !opts.DryRun {

internal/restic/snapshot_find.go

@@ -24,7 +24,7 @@ type SnapshotFilter struct {
 	TimestampLimit time.Time
 }
 
-func (f *SnapshotFilter) empty() bool {
+func (f *SnapshotFilter) Empty() bool {
 	return len(f.Hosts)+len(f.Tags)+len(f.Paths) == 0
 }
 
@@ -173,7 +173,7 @@ func (f *SnapshotFilter) FindAll(ctx context.Context, be Lister, loader LoaderUn
 		}
 
 		// Give the user some indication their filters are not used.
-		if !usedFilter && !f.empty() {
+		if !usedFilter && !f.Empty() {
 			return fn("filters", nil, errors.Errorf("explicit snapshot ids are given"))
 		}
 		return nil

internal/restic/snapshot_group.go

@@ -66,6 +66,20 @@ type SnapshotGroupKey struct {
 	Tags     []string `json:"tags"`
 }
 
+func (s *SnapshotGroupKey) String() string {
+	var parts []string
+	if s.Hostname != "" {
+		parts = append(parts, fmt.Sprintf("host %v", s.Hostname))
+	}
+	if len(s.Paths) != 0 {
+		parts = append(parts, fmt.Sprintf("path %v", s.Paths))
+	}
+	if len(s.Tags) != 0 {
+		parts = append(parts, fmt.Sprintf("tags %v", s.Tags))
+	}
+	return strings.Join(parts, ", ")
+}
+
 // GroupSnapshots takes a list of snapshots and a grouping criteria and creates
 // a grouped list of snapshots.
 func GroupSnapshots(snapshots Snapshots, groupBy SnapshotGroupByOptions) (map[string]Snapshots, bool, error) {

internal/restic/snapshot_policy.go

@@ -94,7 +94,11 @@ func (e ExpirePolicy) String() (s string) {
 		s += fmt.Sprintf("all snapshots within %s of the newest", e.Within)
 	}
 
+	if s == "" {
+		s = "remove"
+	} else {
 		s = "keep " + s
+	}
 
 	return s
 }
@@ -186,16 +190,6 @@ func ApplyPolicy(list Snapshots, p ExpirePolicy) (keep, remove Snapshots, reason
 	// sort newest snapshots first
 	sort.Stable(list)
 
-	if p.Empty() {
-		for _, sn := range list {
-			reasons = append(reasons, KeepReason{
-				Snapshot: sn,
-				Matches:  []string{"policy is empty"},
-			})
-		}
-		return list, remove, reasons
-	}
-
 	if len(list) == 0 {
 		return list, nil, nil
 	}