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
+}