feat: create initial agent for localapi

agent/tsnet/peers.go

@@ -0,0 +1,42 @@
+package tsnet
+
+import (
+	"context"
+	"fmt"
+	"log"
+	"strings"
+	"tailscale.com/tailcfg"
+	"tailscale.com/types/key"
+
+	"go4.org/mem"
+)
+
+// Returns the raw hostinfo for a peer based on node ID.
+func (s *TSAgent) GetStatusForPeer(id string) (*tailcfg.HostinfoView, error) {
+	if !strings.HasPrefix(id, "nodekey:") {
+		return nil, fmt.Errorf("invalid node ID")
+	}
+
+	if s.Debug {
+		log.Printf("querying peer state for %s", id)
+	}
+
+	status, err := s.Lc.Status(context.Background())
+	if err != nil {
+		return nil, fmt.Errorf("failed to get status: %w", err)
+	}
+
+	nodeKey, err := key.ParseNodePublicUntyped(mem.S(id[8:]))
+	peer := status.Peer[nodeKey]
+	if peer == nil {
+		return nil, nil
+	}
+
+	ip := peer.TailscaleIPs[0].String()
+	whois, err := s.Lc.WhoIs(context.Background(), ip)
+	if err != nil {
+		return nil, fmt.Errorf("failed to get whois: %w", err)
+	}
+
+	return &whois.Node.Hostinfo, nil
+}

agent/tsnet/server.go

@@ -0,0 +1,61 @@
+package tsnet
+
+import (
+	"context"
+	"fmt"
+	"log"
+	"os"
+
+	"tailscale.com/client/tailscale"
+	"tailscale.com/tsnet"
+)
+
+// Wrapper type so we can add methods to the server.
+type TSAgent struct {
+	*tsnet.Server
+	Lc *tailscale.LocalClient
+	ID string
+	Debug bool
+}
+
+// Creates a new tsnet agent and returns an instance of the server.
+func NewAgent(hostname, controlURL, authKey string, debug bool) *TSAgent {
+	s := &tsnet.Server{
+		Hostname:   hostname,
+		ControlURL: controlURL,
+		AuthKey:    authKey,
+		Logf:       func(string, ...interface{}) {}, // Disabled by default
+	}
+
+	if debug {
+		s.Logf = log.New(
+			os.Stderr,
+			fmt.Sprintf("[DBG:%s] ", hostname),
+			log.LstdFlags,
+		).Printf
+	}
+
+	return &TSAgent{s, nil, "", debug}
+}
+
+// Starts the tsnet agent and sets the node ID.
+func (s *TSAgent) StartAndFetchID() {
+	// Waits until the agent is up and running.
+	status, err := s.Up(context.Background())
+	if err != nil {
+		log.Fatalf("Failed to start agent: %v", err)
+	}
+
+	s.Lc, err = s.LocalClient()
+	if err != nil {
+		log.Fatalf("Failed to create local client: %v", err)
+	}
+
+	log.Printf("Agent running with ID: %s", status.Self.PublicKey)
+	s.ID = string(status.Self.ID)
+}
+
+// Shuts down the tsnet agent.
+func (s *TSAgent) Shutdown() {
+	s.Close()
+}