Make snapshots dirs in mount command customizable

changelog/unreleased/issue-2907

@@ -0,0 +1,7 @@
+Enhancement: Make snapshot directory structure of mount command custimizable
+
+We've added the possibility to customize the snapshot directory structure of the mount command.
+This includes using subdirectories which is now also possible within time template and tags.
+
+https://github.com/restic/restic/issues/2907
+https://github.com/restic/restic/pull/2913

cmd/restic/cmd_mount.go

@@ -5,6 +5,7 @@ package main
 
 import (
 	"os"
+	"strings"
 	"time"
 
 	"github.com/spf13/cobra"
@@ -30,10 +31,13 @@ read-only mount.
 Snapshot Directories
 ====================
 
-If you need a different template for all directories that contain snapshots,
-you can pass a template via --snapshot-template. Example without colons:
+If you need a different template for directories that contain snapshots,
+you can pass a time template via --time-template and path templates via
+--path-template.
 
-    --snapshot-template "2006-01-02_15-04-05"
+Example time template without colons:
+
+    --time-template "2006-01-02_15-04-05"
 
 You need to specify a sample format for exactly the following timestamp:
 
@@ -42,6 +46,20 @@ You need to specify a sample format for exactly the following timestamp:
 For details please see the documentation for time.Format() at:
   https://godoc.org/time#Time.Format
 
+For path templates, you can use the following patterns which will be replaced:
+    %i by short snapshot ID
+    %I by long snapshot ID
+    %u by username
+    %h by hostname
+    %t by tags
+    %T by timestamp as specified by --time-template
+
+The default path templates are:
+    "ids/%i"
+    "snapshots/%T"
+    "hosts/%h/%T"
+    "tags/%t/%T"
+
 EXIT STATUS
 ===========
 
@@ -61,7 +79,8 @@ type MountOptions struct {
 	Hosts                []string
 	Tags                 restic.TagLists
 	Paths                []string
-	SnapshotTemplate     string
+	TimeTemplate         string
+	PathTemplates        []string
 }
 
 var mountOptions MountOptions
@@ -78,13 +97,21 @@ func init() {
 	mountFlags.Var(&mountOptions.Tags, "tag", "only consider snapshots which include this `taglist`")
 	mountFlags.StringArrayVar(&mountOptions.Paths, "path", nil, "only consider snapshots which include this (absolute) `path`")
 
-	mountFlags.StringVar(&mountOptions.SnapshotTemplate, "snapshot-template", time.RFC3339, "set `template` to use for snapshot dirs")
+	mountFlags.StringArrayVar(&mountOptions.PathTemplates, "path-template", nil, "set `template` for path names (can be specified multiple times)")
+	mountFlags.StringVar(&mountOptions.TimeTemplate, "snapshot-template", time.RFC3339, "set `template` to use for snapshot dirs")
+	mountFlags.StringVar(&mountOptions.TimeTemplate, "time-template", time.RFC3339, "set `template` to use for times")
+	_ = mountFlags.MarkDeprecated("snapshot-template", "use --time-template")
 }
 
 func runMount(opts MountOptions, gopts GlobalOptions, args []string) error {
-	if opts.SnapshotTemplate == "" {
-		return errors.Fatal("snapshot template string cannot be empty")
+	if opts.TimeTemplate == "" {
+		return errors.Fatal("time template string cannot be empty")
 	}
+
+	if strings.HasPrefix(opts.TimeTemplate, "/") || strings.HasSuffix(opts.TimeTemplate, "/") {
+		return errors.Fatal("time template string cannot start or end with '/'")
+	}
+
 	if len(args) == 0 {
 		return errors.Fatal("wrong number of parameters")
 	}
@@ -154,7 +181,8 @@ func runMount(opts MountOptions, gopts GlobalOptions, args []string) error {
 		Hosts:         opts.Hosts,
 		Tags:          opts.Tags,
 		Paths:         opts.Paths,
-		SnapshotTemplate: opts.SnapshotTemplate,
+		TimeTemplate:  opts.TimeTemplate,
+		PathTemplates: opts.PathTemplates,
 	}
 	root := fuse.NewRoot(repo, cfg)
 

cmd/restic/integration_fuse_test.go

@@ -55,7 +55,7 @@ func waitForMount(t testing.TB, dir string) {
 
 func testRunMount(t testing.TB, gopts GlobalOptions, dir string) {
 	opts := MountOptions{
-		SnapshotTemplate: time.RFC3339,
+		TimeTemplate: time.RFC3339,
 	}
 	rtest.OK(t, runMount(opts, gopts, []string{dir}))
 }

internal/fuse/root.go

@@ -19,7 +19,8 @@ type Config struct {
 	Hosts         []string
 	Tags          []restic.TagList
 	Paths         []string
-	SnapshotTemplate string
+	TimeTemplate  string
+	PathTemplates []string
 }
 
 // Root is the root node of the fuse mount of a repository.
@@ -59,14 +60,17 @@ func NewRoot(repo restic.Repository, cfg Config) *Root {
 		root.gid = uint32(os.Getgid())
 	}
 
-	paths := []string{
+	// set defaults, if PathTemplates is not set
+	if len(cfg.PathTemplates) == 0 {
+		cfg.PathTemplates = []string{
 			"ids/%i",
 			"snapshots/%T",
 			"hosts/%h/%T",
 			"tags/%t/%T",
 		}
+	}
 
-	root.SnapshotsDir = NewSnapshotsDir(root, rootInode, NewSnapshotsDirStructure(root, paths, cfg.SnapshotTemplate), "")
+	root.SnapshotsDir = NewSnapshotsDir(root, rootInode, NewSnapshotsDirStructure(root, cfg.PathTemplates, cfg.TimeTemplate), "")
 
 	return root
 }