cmd/tailscale: remove dep on clientupdate package if feature is omitted

We already had a featuretag for clientupdate, but the CLI wasn't using
it, making the "minbox" build (minimal combined tailscaled + CLI
build) larger than necessary.

Updates #12614

Change-Id: Idd7546c67dece7078f25b8f2ae9886f58d599002
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>

cmd/tailscale/cli/cli.go

@@ -219,6 +219,7 @@ var (
 	maybeFunnelCmd,
 	maybeServeCmd,
 	maybeCertCmd,
+	maybeUpdateCmd,
 	_ func() *ffcli.Command
 )
 
@@ -270,7 +271,7 @@ change in the future.
 			nilOrCall(maybeNetlockCmd),
 			licensesCmd,
 			exitNodeCmd(),
-			updateCmd,
+			nilOrCall(maybeUpdateCmd),
 			whoisCmd,
 			debugCmd(),
 			nilOrCall(maybeDriveCmd),

cmd/tailscale/cli/update.go

@@ -1,6 +1,8 @@
 // Copyright (c) Tailscale Inc & contributors
 // SPDX-License-Identifier: BSD-3-Clause
 
+//go:build !ts_omit_clientupdate
+
 package cli
 
 import (
@@ -17,6 +19,14 @@ import (
 	"tailscale.com/version/distro"
 )
 
+func init() {
+	maybeUpdateCmd = func() *ffcli.Command { return updateCmd }
+
+	clientupdateLatestTailscaleVersion.Set(func() (string, error) {
+		return clientupdate.LatestTailscaleVersion(clientupdate.CurrentTrack)
+	})
+}
+
 var updateCmd = &ffcli.Command{
 	Name:       "update",
 	ShortUsage: "tailscale update",

cmd/tailscale/cli/version.go

@@ -10,7 +10,7 @@ import (
 	"fmt"
 
 	"github.com/peterbourgon/ff/v3/ffcli"
-	"tailscale.com/clientupdate"
+	"tailscale.com/feature"
 	"tailscale.com/ipn/ipnstate"
 	"tailscale.com/version"
 )
@@ -35,6 +35,8 @@ var versionArgs struct {
 	upstream bool
 }
 
+var clientupdateLatestTailscaleVersion feature.Hook[func() (string, error)]
+
 func runVersion(ctx context.Context, args []string) error {
 	if len(args) > 0 {
 		return fmt.Errorf("too many non-flag arguments: %q", args)
@@ -51,7 +53,11 @@ func runVersion(ctx context.Context, args []string) error {
 
 	var upstreamVer string
 	if versionArgs.upstream {
-		upstreamVer, err = clientupdate.LatestTailscaleVersion(clientupdate.CurrentTrack)
+		f, ok := clientupdateLatestTailscaleVersion.GetOk()
+		if !ok {
+			return fmt.Errorf("fetching latest version not supported in this build")
+		}
+		upstreamVer, err = f()
 		if err != nil {
 			return err
 		}

cmd/tailscaled/depaware-minbox.txt

@@ -1,7 +1,5 @@
 tailscale.com/cmd/tailscaled dependencies: (generated by github.com/tailscale/depaware)
 
-        filippo.io/edwards25519                                      from github.com/hdevalence/ed25519consensus
-        filippo.io/edwards25519/field                                from filippo.io/edwards25519
         github.com/gaissmai/bart                                     from tailscale.com/net/ipset+
         github.com/gaissmai/bart/internal/bitset                     from github.com/gaissmai/bart+
         github.com/gaissmai/bart/internal/sparse                     from github.com/gaissmai/bart
@@ -12,7 +10,6 @@ tailscale.com/cmd/tailscaled dependencies: (generated by github.com/tailscale/de
         github.com/go-json-experiment/json/internal/jsonwire         from github.com/go-json-experiment/json+
         github.com/go-json-experiment/json/jsontext                  from github.com/go-json-experiment/json+
         github.com/golang/groupcache/lru                             from tailscale.com/net/dnscache
-        github.com/hdevalence/ed25519consensus                       from tailscale.com/clientupdate/distsign
      💣 github.com/jsimonetti/rtnetlink                              from tailscale.com/net/netmon
         github.com/jsimonetti/rtnetlink/internal/unix                from github.com/jsimonetti/rtnetlink
         github.com/kballard/go-shellquote                            from tailscale.com/cmd/tailscale/cli
@@ -50,8 +47,6 @@ tailscale.com/cmd/tailscaled dependencies: (generated by github.com/tailscale/de
         tailscale.com/client/local                                   from tailscale.com/client/tailscale+
         tailscale.com/client/tailscale                               from tailscale.com/internal/client/tailscale
         tailscale.com/client/tailscale/apitype                       from tailscale.com/ipn/ipnauth+
-        tailscale.com/clientupdate                                   from tailscale.com/cmd/tailscale/cli
-        tailscale.com/clientupdate/distsign                          from tailscale.com/clientupdate
         tailscale.com/cmd/tailscale/cli                              from tailscale.com/cmd/tailscaled
         tailscale.com/cmd/tailscale/cli/ffcomplete                   from tailscale.com/cmd/tailscale/cli
         tailscale.com/cmd/tailscale/cli/ffcomplete/internal          from tailscale.com/cmd/tailscale/cli/ffcomplete
@@ -175,7 +170,6 @@ tailscale.com/cmd/tailscaled dependencies: (generated by github.com/tailscale/de
         tailscale.com/util/clientmetric                              from tailscale.com/appc+
         tailscale.com/util/cloudenv                                  from tailscale.com/hostinfo+
         tailscale.com/util/cloudinfo                                 from tailscale.com/wgengine/magicsock
-        tailscale.com/util/cmpver                                    from tailscale.com/clientupdate
         tailscale.com/util/ctxkey                                    from tailscale.com/client/tailscale/apitype+
         tailscale.com/util/dnsname                                   from tailscale.com/appc+
         tailscale.com/util/eventbus                                  from tailscale.com/client/local+
@@ -268,7 +262,6 @@ tailscale.com/cmd/tailscaled dependencies: (generated by github.com/tailscale/de
         vendor/golang.org/x/text/transform                           from vendor/golang.org/x/text/secure/bidirule+
         vendor/golang.org/x/text/unicode/bidi                        from vendor/golang.org/x/net/idna+
         vendor/golang.org/x/text/unicode/norm                        from vendor/golang.org/x/net/idna
-        archive/tar                                                  from tailscale.com/clientupdate
         bufio                                                        from compress/flate+
         bytes                                                        from bufio+
         cmp                                                          from encoding/json+
@@ -428,7 +421,7 @@ tailscale.com/cmd/tailscaled dependencies: (generated by github.com/tailscale/de
         path                                                         from io/fs+
         path/filepath                                                from crypto/x509+
         reflect                                                      from crypto/x509+
-        regexp                                                       from tailscale.com/clientupdate+
+        regexp                                                       from tailscale.com/cmd/tailscale/cli
         regexp/syntax                                                from regexp
         runtime                                                      from crypto/internal/fips140+
         runtime/debug                                                from github.com/klauspost/compress/zstd+

cmd/tailscaled/deps_test.go

@@ -285,9 +285,14 @@ func TestMinTailscaledWithCLI(t *testing.T) {
 			}
 		},
 		BadDeps: map[string]string{
-			"golang.org/x/net/http2":        "unexpected x/net/http2 dep; tailscale/tailscale#17305",
-			"expvar":                        "unexpected expvar dep",
-			"github.com/mdlayher/genetlink": "unexpected genetlink dep",
+			"golang.org/x/net/http2":                 "unexpected x/net/http2 dep; tailscale/tailscale#17305",
+			"expvar":                                 "unexpected expvar dep",
+			"github.com/mdlayher/genetlink":          "unexpected genetlink dep",
+			"tailscale.com/clientupdate":             "unexpected clientupdate dep",
+			"filippo.io/edwards25519":                "unexpected edwards25519 dep",
+			"github.com/hdevalence/ed25519consensus": "unexpected ed25519consensus dep",
+			"tailscale.com/clientupdate/distsign":    "unexpected distsign dep",
+			"archive/tar":                            "unexpected archive/tar dep",
 		},
 	}.Check(t)
 }