cmd/tailscale/cli: Remove advertise command and add drain to serve

This commit removes the advertise command for advertising services on service host. The advertising
of service is merged into serve command with --service flag. Unadvertising is now a subcommand of
serve named drain. According to the DACI, we now only remove serve config when we attach "off" arg
after a specific service proxy config. Simply attaching off after a --service flag doesn't do
anything now.

Updates tailscale/corp#22954
Fixes tailscale/corp#28016

Signed-off-by: KevinLiang10 <37811973+KevinLiang10@users.noreply.github.com>

cmd/tailscale/cli/advertise.go

@@ -1,95 +0,0 @@
-// Copyright (c) Tailscale Inc & AUTHORS
-// SPDX-License-Identifier: BSD-3-Clause
-
-package cli
-
-import (
-	"context"
-	"flag"
-	"fmt"
-	"strings"
-
-	"github.com/peterbourgon/ff/v3/ffcli"
-	"tailscale.com/envknob"
-	"tailscale.com/ipn"
-	"tailscale.com/tailcfg"
-)
-
-var advertiseArgs struct {
-	services string // comma-separated list of services to advertise
-}
-
-// TODO(naman): This flag may move to set.go or serve_v2.go after the WIPCode
-// envknob is not needed.
-func advertiseCmd() *ffcli.Command {
-	if !envknob.UseWIPCode() {
-		return nil
-	}
-	return &ffcli.Command{
-		Name:       "advertise",
-		ShortUsage: "tailscale advertise --services=<services>",
-		ShortHelp:  "Advertise this node as a destination for a service",
-		Exec:       runAdvertise,
-		FlagSet: (func() *flag.FlagSet {
-			fs := newFlagSet("advertise")
-			fs.StringVar(&advertiseArgs.services, "services", "", "comma-separated services to advertise; each must start with \"svc:\" (e.g. \"svc:idp,svc:nas,svc:database\")")
-			return fs
-		})(),
-	}
-}
-
-func runAdvertise(ctx context.Context, args []string) error {
-	if len(args) > 0 {
-		return flag.ErrHelp
-	}
-
-	services, err := parseServiceNames(advertiseArgs.services)
-	if err != nil {
-		return err
-	}
-	if len(services) > 0 {
-		fmt.Println("Advertising this node as new destination for services:", services)
-		fmt.Println("This node will accept connection for services once the services are configured locally and approved on the admin console.")
-		sc, err := localClient.GetServeConfig(ctx)
-		if err != nil {
-			return fmt.Errorf("failed to get serve config: %w", err)
-		}
-		notServedServices := make([]string, 0)
-		for _, svc := range services {
-			if _, ok := sc.Services[tailcfg.ServiceName(svc)]; !ok {
-				notServedServices = append(notServedServices, svc)
-			}
-		}
-		if len(notServedServices) > 0 {
-			fmt.Println("The following services are not configured to be served yet: ", strings.Join(notServedServices, ", "))
-			fmt.Println("To configure services, run tailscale serve --service=\"<svc:dns-label>\" for each service.")
-			fmt.Printf("eg. tailscale serve --service=%q 3000\n", notServedServices[0])
-		}
-	}
-
-	_, err = localClient.EditPrefs(ctx, &ipn.MaskedPrefs{
-		AdvertiseServicesSet: true,
-		Prefs: ipn.Prefs{
-			AdvertiseServices: services,
-		},
-	})
-	return err
-}
-
-// parseServiceNames takes a comma-separated list of service names
-// (eg. "svc:hello,svc:webserver,svc:catphotos"), splits them into
-// a list and validates each service name. If valid, it returns
-// the service names in a slice of strings.
-func parseServiceNames(servicesArg string) ([]string, error) {
-	var services []string
-	if servicesArg != "" {
-		services = strings.Split(servicesArg, ",")
-		for _, svc := range services {
-			err := tailcfg.ServiceName(svc).Validate()
-			if err != nil {
-				return nil, fmt.Errorf("service %q: %s", svc, err)
-			}
-		}
-	}
-	return services, nil
-}

cmd/tailscale/cli/serve_legacy.go

@@ -142,6 +142,7 @@ type localServeClient interface {
 	WatchIPNBus(ctx context.Context, mask ipn.NotifyWatchOpt) (*tailscale.IPNBusWatcher, error)
 	IncrementCounter(ctx context.Context, name string, delta int) error
 	GetPrefs(ctx context.Context) (*ipn.Prefs, error)
+	EditPrefs(ctx context.Context, mp *ipn.MaskedPrefs) (*ipn.Prefs, error)
 }
 
 // serveEnv is the environment the serve command runs within. All I/O should be

cmd/tailscale/cli/serve_v2.go

@@ -353,12 +353,11 @@ func (e *serveEnv) runServeCombined(subcmd serveMode) execFunc {
 
 		var msg string
 		if turnOff {
-			if wasDefaultServe && forService {
-				delete(sc.Services, tailcfg.ServiceName(dnsName))
-			} else {
+			if !wasDefaultServe { // only unset serve when trying to unset with parameters.
 				err = e.unsetServe(sc, st, dnsName, srvType, srvPort, mount)
 			}
 		} else {
+			e.addServiceToPrefs(ctx, dnsName)
 			if err := e.validateConfig(parentSC, srvPort, srvType, dnsName); err != nil {
 				return err
 			}
@@ -367,7 +366,7 @@ func (e *serveEnv) runServeCombined(subcmd serveMode) execFunc {
 				target = args[0]
 			}
 			err = e.setServe(sc, st, dnsName, srvType, srvPort, mount, target, funnel)
-			msg = e.messageForPort(sc, st, prefs, dnsName, srvType, srvPort)
+			msg = e.messageForPort(sc, st, dnsName, srvType, srvPort)
 		}
 		if err != nil {
 			fmt.Fprintf(e.stderr(), "error: %v\n\n", err)
@@ -502,14 +501,13 @@ var (
 	msgDisableProxy         = "To disable the proxy, run: tailscale %s --%s=%d off"
 	msgDisableServiceProxy  = "To disable the proxy, run: tailscale serve --service=%s --%s=%d off"
 	msgDisableServiceTun    = "To disable the service in TUN mode, run: tailscale serve --service=%s --tun off"
-	msgDisableService       = "To disable the service entirely, run: tailscale serve --service=%s off"
-	msgServiceNotAdvertised = "This service is not advertised on this node yet, use `tailscale advertise --services=svc:%s` to advertise it."
+	msgDisableService       = "To remove config for the service, run: tailscale serve clear --service=%s"
 	msgToExit               = "Press Ctrl+C to exit."
 )
 
 // messageForPort returns a message for the given port based on the
 // serve config and status.
-func (e *serveEnv) messageForPort(sc *ipn.ServeConfig, st *ipnstate.Status, prefs *ipn.Prefs, dnsName string, srvType serveType, srvPort uint16) string {
+func (e *serveEnv) messageForPort(sc *ipn.ServeConfig, st *ipnstate.Status, dnsName string, srvType serveType, srvPort uint16) string {
 	var output strings.Builder
 	forService := ipn.IsServiceName(dnsName)
 	var hp ipn.HostPort
@@ -618,10 +616,6 @@ func (e *serveEnv) messageForPort(sc *ipn.ServeConfig, st *ipnstate.Status, pref
 	output.WriteString(fmt.Sprintf(msgRunningInBackground, subCmdUpper))
 	output.WriteString("\n")
 	if forService {
-		if !slices.Contains(prefs.AdvertiseServices, dnsName) {
-			output.WriteString(fmt.Sprintf(msgServiceNotAdvertised, dnsName))
-			output.WriteString("\n")
-		}
 		output.WriteString(fmt.Sprintf(msgDisableServiceProxy, dnsName, srvType.String(), srvPort))
 		output.WriteString("\n")
 		output.WriteString(fmt.Sprintf(msgDisableService, dnsName))