restic · ducalex · Apr 2, 2024 · Apr 2, 2024 · Apr 2, 2024 · Apr 6, 2024
diff --git a/changelog/unreleased/pull-4276 b/changelog/unreleased/pull-4276
@@ -0,0 +1,13 @@
+Enhancement: Implement web server to browse snapshots
+
+Currently the canonical way of browsing a repository's snapshots to view
+or restore files is `mount`. Unfortunately `mount` depends on fuse which
+is not available on all operating systems.
+
+The new `restic serve` command presents a web interface to browse a
+repository's snapshots. It allows to view and download files individually
+or as a group (as a tar archive) from snapshots.
+
+https://github.com/restic/restic/pull/4276
+https://github.com/restic/restic/issues/60
+
diff --git a/cmd/restic/cmd_serve.go b/cmd/restic/cmd_serve.go
@@ -0,0 +1,103 @@
+package main
+
+import (
+	"context"
+	"fmt"
+	"net"
+	"net/http"
+	"time"
+
+	"github.com/spf13/cobra"
+
+	"github.com/restic/restic/internal/errors"
+	"github.com/restic/restic/internal/restic"
+	"github.com/restic/restic/internal/server"
+)
+
+var cmdServe = &cobra.Command{
+	Use:   "serve",
+	Short: "runs a web server to browse a repository",
+	Long: `
+The serve command runs a web server to browse a repository.
+`,
+	DisableAutoGenTag: true,
+	RunE: func(cmd *cobra.Command, args []string) error {
+		return runWebServer(cmd.Context(), serveOptions, globalOptions, args)
+	},
+}
+
+type ServeOptions struct {
+	Listen string
+}
+
+var serveOptions ServeOptions
+
+func init() {
+	cmdRoot.AddCommand(cmdServe)
+	cmdFlags := cmdServe.Flags()
+	cmdFlags.StringVarP(&serveOptions.Listen, "listen", "l", "localhost:3080", "set the listen host name and `address`")
+}
+
+const serverShutdownTimeout = 30 * time.Second
+
+func runWebServer(ctx context.Context, opts ServeOptions, gopts GlobalOptions, args []string) error {
+	if len(args) > 0 {
+		return errors.Fatal("this command does not accept additional arguments")
+	}
+
+	ctx, repo, unlock, err := openWithExclusiveLock(ctx, gopts, gopts.NoLock)
+	if err != nil {
+		return err
+	}
+	defer unlock()
+
+	snapshotLister, err := restic.MemorizeList(ctx, repo, restic.SnapshotFile)
+	if err != nil {
+		return err
+	}
+
+	bar := newIndexProgress(gopts.Quiet, gopts.JSON)
+	err = repo.LoadIndex(ctx, bar)
+	if err != nil {
+		return err
+	}
+
+	srv := http.Server{
+		BaseContext: func(l net.Listener) context.Context {
+			// just return the global context
+			return ctx
+		},
+		Handler: server.New(repo, snapshotLister, TimeFormat),
+	}
+
+	listener, err := net.Listen("tcp", opts.Listen)
+	if err != nil {
+		return fmt.Errorf("start listener: %v", err)
+	}
+
+	// wait until context is cancelled, then close listener
+	go func() {
+		<-ctx.Done()
+		Printf("gracefully shutting down server\n")
+
+		ctxTimeout, cancel := context.WithTimeout(context.Background(), serverShutdownTimeout)
+		defer cancel()
+
+		_ = srv.Shutdown(ctxTimeout)
+	}()
+
+	Printf("Now serving the repository at http://%s\n", opts.Listen)
+	Printf("When finished, quit with Ctrl-c here.\n")
+
+	err = srv.Serve(listener)
+
+	if errors.Is(err, http.ErrServerClosed) {
+		err = nil
+	}
+
+	if err != nil {
+		return fmt.Errorf("serve: %v", err)
+	}
+
+	return nil
+}
diff --git a/internal/server/assets/fs.go b/internal/server/assets/fs.go
@@ -0,0 +1,6 @@
+package assets
+
+import "embed"
+
+//go:embed *
+var FS embed.FS
diff --git a/internal/server/assets/index.html b/internal/server/assets/index.html
@@ -0,0 +1,34 @@
+<html>
+
+<head>
+    <link rel="stylesheet" href="/style.css">
+    <title>{{.Title}} :: restic</title>
+</head>
+
+<body>
+    <h1>{{.Title}}</h1>
+    <table>
+        <thead>
+            <tr>
+                <th>ID</th>
+                <th>Time</th>
+                <th>Host</th>
+                <th>Tags</th>
+                <th>Paths</th>
+            </tr>
+        </thead>
+        <tbody>
+            {{range .Rows}}
+            <tr>
+                <td><a href="{{.Link}}">{{.ID}}</a></td>
+                <td>{{.Time | FormatTime}}</td>
+                <td>{{.Host}}</td>
+                <td>{{.Tags}}</td>
+                <td>{{.Paths}}</td>
+            </tr>
+            {{end}}
+        </tbody>
+    </table>
+</body>
+
+</html>
diff --git a/internal/server/assets/style.css b/internal/server/assets/style.css
@@ -0,0 +1,40 @@
+h1,
+h2,
+h3 {
+    text-align: center;
+    margin: 0.5em;
+}
+
+table {
+    margin: 0 auto;
+    border-collapse: collapse;
+}
+
+thead th {
+    text-align: left;
+    font-weight: bold;
+}
+
+tbody.content tr:hover {
+    background: #eee;
+}
+
+tbody.content a.file:before {
+    content: '\1F4C4'
+}
+
+tbody.content a.dir:before {
+    content: '\1F4C1'
+}
+
+tbody.actions td {
+    padding: .5em;
+}
+
+table,
+td,
+tr,
+th {
+    border: 1px solid black;
+    padding: .1em .5em;
+}
diff --git a/internal/server/assets/tree.html b/internal/server/assets/tree.html
@@ -0,0 +1,51 @@
+<html>
+
+<head>
+    <link rel="stylesheet" href="/style.css">
+    <title>{{.Title}} :: restic</title>
+</head>
+
+<body>
+    <h1>{{.Title}}</h1>
+    <form method="post">
+        <table>
+            <thead>
+                <tr>
+                    <th><input type="checkbox"
+                            onclick="document.querySelectorAll('.content input[type=checkbox]').forEach(cb => cb.checked = this.checked)">
+                    </th>
+                    <th>Name</th>
+                    <th>Type</th>
+                    <th>Size</th>
+                    <th>Date modified</th>
+                </tr>
+            </thead>
+            <tbody class="content">
+                {{if .Parent}}<tr>
+                    <td></td>
+                    <td><a href="{{.Parent}}">..</a></td>
+                    <td>parent</td>
+                    <td></td>
+                    <td>
+                </tr>{{end}}
+                {{range .Rows}}
+                <tr>
+                    <td><input type="checkbox" name="name" value="{{.Name}}"></td>
+                    <td><a class="{{.Type}}" href="{{.Link}}">{{.Name}}</a></td>
+                    <td>{{.Type}}</td>
+                    <td>{{.Size}}</td>
+                    <td>{{.Time | FormatTime}}</td>
+                    </td>
+                </tr>
+                {{end}}
+            </tbody>
+            <tbody class="actions">
+                <tr>
+                    <td colspan="100"><button name="action" value="dump" type="submit">Download selection</button></td>
+                </tr>
+            </tbody>
+        </table>
+    </form>
+</body>
+
+</html>