Pull request: 4223 home: cmd update

Merge in DNS/adguard-home from 4223-cmd-update to master

Squashed commit of the following:

commit ffda71246f37eaba0cb190840f1370ba65099d7c
Author: Dimitry Kolyshev <dkolyshev@adguard.com>
Date:   Tue Nov 15 16:32:10 2022 +0200

    home: cmd update

commit 9c4e1c33da78952a2b1477ac380a0cf042a8990f
Author: Dimitry Kolyshev <dkolyshev@adguard.com>
Date:   Tue Nov 15 13:51:33 2022 +0200

    home: cmd update

commit 6a564dc30771b3675e8861ca3befaaee15d83026
Author: Dimitry Kolyshev <dkolyshev@adguard.com>
Date:   Mon Nov 14 11:05:06 2022 +0200

    all: docs

commit a546bdbdb6f3f78c40908bc1864f2a1ae1c9071f
Author: Dimitry Kolyshev <dkolyshev@adguard.com>
Date:   Mon Nov 14 10:55:16 2022 +0200

    home: cmd update

commit cbbb594980d3d163fe0489494b0ddca5f679d6e6
Author: Dimitry Kolyshev <dkolyshev@adguard.com>
Date:   Mon Nov 14 10:16:09 2022 +0200

    home: imp code

commit 677f8a7ca0f47da0ac636e5bab9db24506cf5041
Author: Dimitry Kolyshev <dkolyshev@adguard.com>
Date:   Sun Nov 13 14:12:48 2022 +0200

    home: cmd update

CHANGELOG.md

@@ -25,6 +25,13 @@ See also the [v0.107.19 GitHub milestone][ms-v0.107.19].
 [ms-v0.107.19]: https://github.com/AdguardTeam/AdGuardHome/milestone/55?closed=1
 -->
 
+### Added
+
+- The new `--update` command-line option, which allows updating AdGuard Home
+  silently ([#4223]).
+
+[#4223]: https://github.com/AdguardTeam/AdGuardHome/issues/4223
+
 
 
 ## [v0.107.18] - 2022-11-08

internal/home/home.go

@@ -542,6 +542,11 @@ func run(opts options, clientBuildFS fs.FS) {
 		}
 	}
 
+	// TODO(a.garipov): This could be made much earlier and could be done on
+	// the first run as well, but to achieve this we need to bypass requests
+	// over dnsforward resolver.
+	cmdlineUpdate(opts)
+
 	Context.web.Start()
 
 	// wait indefinitely for other go-routines to complete their job
@@ -927,3 +932,37 @@ type jsonError struct {
 	// Message is the error message, an opaque string.
 	Message string `json:"message"`
 }
+
+// cmdlineUpdate updates current application and exits.
+func cmdlineUpdate(opts options) {
+	if !opts.performUpdate {
+		return
+	}
+
+	log.Info("starting update")
+
+	if Context.firstRun {
+		log.Info("update not allowed on first run")
+
+		os.Exit(0)
+	}
+
+	_, err := Context.updater.VersionInfo(true)
+	if err != nil {
+		vcu := Context.updater.VersionCheckURL()
+		log.Error("getting version info from %s: %s", vcu, err)
+
+		os.Exit(0)
+	}
+
+	if Context.updater.NewVersion() == "" {
+		log.Info("no updates available")
+
+		os.Exit(0)
+	}
+
+	err = Context.updater.Update()
+	fatalOnError(err)
+
+	os.Exit(0)
+}

internal/home/options.go

@@ -47,6 +47,9 @@ type options struct {
 	// disableUpdate, if set, makes AdGuard Home not check for updates.
 	disableUpdate bool
 
+	// performUpdate, if set, updates AdGuard Home without GUI and exits.
+	performUpdate bool
+
 	// verbose shows if verbose logging is enabled.
 	verbose bool
 
@@ -221,6 +224,14 @@ var cmdLineOpts = []cmdLineOpt{{
 	description:     "Don't check for updates.",
 	longName:        "no-check-update",
 	shortName:       "",
+}, {
+	updateWithValue: nil,
+	updateNoValue:   func(o options) (options, error) { o.performUpdate = true; return o, nil },
+	effect:          nil,
+	serialize:       func(o options) (val string, ok bool) { return "", o.performUpdate },
+	description:     "Update application and exit.",
+	longName:        "update",
+	shortName:       "",
 }, {
 	updateWithValue: nil,
 	updateNoValue:   nil,

internal/home/options_test.go

@@ -103,6 +103,11 @@ func TestParseDisableUpdate(t *testing.T) {
 	assert.True(t, testParseOK(t, "--no-check-update").disableUpdate, "--no-check-update is disable update")
 }
 
+func TestParsePerformUpdate(t *testing.T) {
+	assert.False(t, testParseOK(t).performUpdate, "empty is not perform update")
+	assert.True(t, testParseOK(t, "--update").performUpdate, "--update is perform update")
+}
+
 // TODO(e.burkov):  Remove after v0.108.0.
 func TestParseDisableMemoryOptimization(t *testing.T) {
 	o, eff, err := parseCmdOpts("", []string{"--no-mem-optimization"})
@@ -169,6 +174,10 @@ func TestOptsToArgs(t *testing.T) {
 		name: "disable_update",
 		args: []string{"--no-check-update"},
 		opts: options{disableUpdate: true},
+	}, {
+		name: "perform_update",
+		args: []string{"--update"},
+		opts: options{performUpdate: true},
 	}, {
 		name: "control_action",
 		args: []string{"-s", "run"},