tsnet,client,cmd/tailscale/cli: expose service details on all clientsadrianosela/proxy-svc-experiment

4 files changed, 129 insertions, 0 deletions

diff --git a/client/local/local.go b/client/local/local.go
index e72589306..0aa0a04b0 100644
--- a/client/local/local.go
+++ b/client/local/local.go
@@ -686,6 +686,18 @@ func (lc *Client) status(ctx context.Context, queryString string) (*ipnstate.Sta
 	return decodeJSON[*ipnstate.Status](body)
 }
 
+// GetServiceDetails returns the VIP services that the control plane has
+// approved this node to serve, including their names, assigned IP addresses,
+// ports, and annotations (e.g. proxy service configuration). Returns nil if
+// no service details are present.
+func (lc *Client) GetServiceDetails(ctx context.Context) ([]*tailcfg.ServiceDetail, error) {
+	body, err := lc.get200(ctx, "/localapi/v0/service-details")
+	if err != nil {
+		return nil, err
+	}
+	return decodeJSON[[]*tailcfg.ServiceDetail](body)
+}
+
 // IDToken is a request to get an OIDC ID token for an audience.
 // The token can be presented to any resource provider which offers OIDC
 // Federation.
diff --git a/cmd/tailscale/cli/cli.go b/cmd/tailscale/cli/cli.go
index 8a2c2b9ef..2bb400ef0 100644
--- a/cmd/tailscale/cli/cli.go
+++ b/cmd/tailscale/cli/cli.go
@@ -269,6 +269,7 @@ change in the future.
 			nilOrCall(maybeNetlockCmd),
 			licensesCmd,
 			exitNodeCmd(),
+			serviceCmd(),
 			nilOrCall(maybeUpdateCmd),
 			whoisCmd,
 			debugCmd(),
diff --git a/cmd/tailscale/cli/service.go b/cmd/tailscale/cli/service.go
new file mode 100644
index 000000000..cde314707
--- /dev/null
+++ b/cmd/tailscale/cli/service.go
@@ -0,0 +1,103 @@
+// Copyright (c) Tailscale Inc & contributors
+// SPDX-License-Identifier: BSD-3-Clause
+
+package cli
+
+import (
+	"context"
+	"encoding/json"
+	"errors"
+	"flag"
+	"fmt"
+	"sort"
+	"strings"
+	"text/tabwriter"
+
+	"github.com/peterbourgon/ff/v3/ffcli"
+	"tailscale.com/tailcfg"
+)
+
+func serviceCmd() *ffcli.Command {
+	return &ffcli.Command{
+		Name:       "service",
+		ShortUsage: "tailscale service <subcommand> [flags]",
+		ShortHelp:  "Manage and inspect Tailscale VIP services",
+		Subcommands: []*ffcli.Command{
+			{
+				Name:       "list",
+				ShortUsage: "tailscale service list [--json]",
+				ShortHelp:  "List VIP services approved for this node",
+				LongHelp: strings.TrimSpace(`
+The 'tailscale service list' command shows the VIP services that the control
+plane has approved this node to serve, including their assigned IP addresses,
+accepted ports, and any application-specific annotations.
+`),
+				Exec: runServiceList,
+				FlagSet: (func() *flag.FlagSet {
+					fs := newFlagSet("list")
+					fs.BoolVar(&serviceArgs.json, "json", false, "output in JSON format")
+					return fs
+				})(),
+			},
+		},
+	}
+}
+
+var serviceArgs struct {
+	json bool
+}
+
+func runServiceList(ctx context.Context, args []string) error {
+	if len(args) > 0 {
+		return errors.New("unexpected non-flag arguments to 'tailscale service list'")
+	}
+	details, err := localClient.GetServiceDetails(ctx)
+	if err != nil {
+		return err
+	}
+	if serviceArgs.json {
+		enc := json.NewEncoder(Stdout)
+		enc.SetIndent("", "  ")
+		enc.Encode(details)
+		return nil
+	}
+	if len(details) == 0 {
+		printf("No VIP services configured for this node.\n")
+		return nil
+	}
+	printServiceDetails(details)
+	return nil
+}
+
+func printServiceDetails(details []*tailcfg.ServiceDetail) {
+	w := tabwriter.NewWriter(Stdout, 0, 0, 3, ' ', 0)
+	fmt.Fprintln(w, "NAME\tADDRS\tPORTS\t")
+	fmt.Fprintln(w, "----\t-----\t-----\t")
+	for _, svc := range details {
+		addrs := make([]string, len(svc.Addrs))
+		for i, a := range svc.Addrs {
+			addrs[i] = a.String()
+		}
+		ports := make([]string, len(svc.Ports))
+		for i, p := range svc.Ports {
+			ports[i] = p.String()
+		}
+		fmt.Fprintf(w, "%s\t%s\t%s\t\n",
+			svc.Name,
+			strings.Join(addrs, ", "),
+			strings.Join(ports, ", "),
+		)
+		if len(svc.Annotations) > 0 {
+			// Print annotations sorted by key, indented under the service row.
+			keys := make([]string, 0, len(svc.Annotations))
+			for k := range svc.Annotations {
+				keys = append(keys, k)
+			}
+			sort.Strings(keys)
+			for _, k := range keys {
+				fmt.Fprintf(w, "  %s: %s\t\t\t\n", k, svc.Annotations[k])
+			}
+		}
+	}
+	w.Flush()
+}
diff --git a/tsnet/tsnet.go b/tsnet/tsnet.go
index f28179773..3360a14f7 100644
--- a/tsnet/tsnet.go
+++ b/tsnet/tsnet.go
@@ -564,6 +564,19 @@ func (s *Server) TailscaleIPs() (ip4, ip6 netip.Addr) {
 	return ip4, ip6
 }
 
+// GetServiceDetails returns the VIP services that the control plane has
+// approved this node to serve, including their names, assigned IP addresses,
+// ports, and application-specific annotations (e.g. proxy service
+// configuration). Returns nil if the server is not running or no service
+// details have been received yet.
+func (s *Server) GetServiceDetails() []*tailcfg.ServiceDetail {
+	nm := s.lb.NetMap()
+	if nm == nil {
+		return nil
+	}
+	return nm.GetVIPServiceDetails()
+}
+
 // LogtailWriter returns an [io.Writer] that writes to Tailscale's logging service and will be only visible to Tailscale's
 // support team. Logs written there cannot be retrieved by the user. This method always returns a non-nil value.
 func (s *Server) LogtailWriter() io.Writer {