From 0a15617c521ea0f574cd035dc9edd4d170f518b2 Mon Sep 17 00:00:00 2001
From: Mikhail <misha_mst@mail.ru>
Date: Sat, 16 May 2026 00:49:18 +0300
Subject: [PATCH] Cover VPN packets in fabric session smoke

---
 .../cmd/mesh-live-smoke/main.go               | 50 +++++++++++++++++++
 .../DISTRIBUTED_FABRIC_NODE_PROTOCOL_PLAN.md  |  3 ++
 2 files changed, 53 insertions(+)

diff --git a/agents/rap-node-agent/cmd/mesh-live-smoke/main.go b/agents/rap-node-agent/cmd/mesh-live-smoke/main.go
index 2b8ca32..1bec065 100644
--- a/agents/rap-node-agent/cmd/mesh-live-smoke/main.go
+++ b/agents/rap-node-agent/cmd/mesh-live-smoke/main.go
@@ -12,6 +12,7 @@ import (
 
 	"github.com/example/remote-access-platform/agents/rap-node-agent/internal/fabricproto"
 	"github.com/example/remote-access-platform/agents/rap-node-agent/internal/mesh"
+	"github.com/example/remote-access-platform/agents/rap-node-agent/internal/vpnruntime"
 )
 
 type smokeNode struct {
@@ -33,6 +34,7 @@ type smokeReport struct {
 	TestServiceEchoPayload  string         `json:"test_service_echo_payload"`
 	FabricSessionAccepted   bool           `json:"fabric_session_accepted"`
 	FabricSessionRoundTrips int            `json:"fabric_session_round_trips"`
+	FabricVPNPacketAccepted bool           `json:"fabric_vpn_packet_accepted"`
 	FabricSessionLatencyMS  int64          `json:"fabric_session_latency_ms"`
 	FabricSessionEndpoint   string         `json:"fabric_session_endpoint"`
 	PeerEndpoints           map[string]any `json:"peer_endpoints"`
@@ -129,6 +131,10 @@ func run(ctx context.Context) (smokeReport, error) {
 		string(firstFabricSessionResponse.Payload) == "mesh-live-smoke-fabric-session" &&
 		secondFabricSessionResponse.Type == fabricproto.FramePong &&
 		string(secondFabricSessionResponse.Payload) == "mesh-live-smoke-fabric-session-2"
+	fabricVPNPacketAccepted, err := smokeFabricVPNPacketOverSession(ctx, fabricSession)
+	if err != nil {
+		return smokeReport{}, fmt.Errorf("fabric vpn packet session smoke: %w", err)
+	}
 
 	return smokeReport{
 		Stage:                   "C17F scoped synthetic config plus live HTTP transport",
@@ -142,6 +148,7 @@ func run(ctx context.Context) (smokeReport, error) {
 		TestServiceEchoPayload:  testService.Response.EchoPayload,
 		FabricSessionAccepted:   fabricSessionAccepted,
 		FabricSessionRoundTrips: 2,
+		FabricVPNPacketAccepted: fabricVPNPacketAccepted,
 		FabricSessionLatencyMS:  fabricSessionLatency.Milliseconds(),
 		FabricSessionEndpoint:   nodeB.URL + "/mesh/v1/fabric/session/ws",
 		PeerEndpoints: map[string]any{
@@ -152,6 +159,49 @@ func run(ctx context.Context) (smokeReport, error) {
 	}, nil
 }
 
+func smokeFabricVPNPacketOverSession(ctx context.Context, fabricSession *mesh.FabricSessionClient) (bool, error) {
+	const streamID uint64 = 4400
+	pump := fabricSession.StartPump(ctx, mesh.FabricSessionPumpOptions{
+		OutboundBuffer: 4,
+		InboundBuffer:  4,
+		ErrorBuffer:    4,
+	})
+	defer pump.Close()
+	if err := pump.Send(ctx, fabricproto.Frame{
+		Type:         fabricproto.FrameOpenStream,
+		StreamID:     streamID,
+		TrafficClass: fabricproto.TrafficClassInteractive,
+	}); err != nil {
+		return false, err
+	}
+	transport := &vpnruntime.FabricSessionPacketTransport{
+		Sender:          pump,
+		StreamID:        streamID,
+		VPNConnectionID: "vpn-smoke",
+		SendDirection:   vpnruntime.FabricDirectionGatewayToClient,
+		TrafficClass:    vpnruntime.FabricTrafficClassInteractive,
+	}
+	if err := transport.SendGatewayPacketBatch(ctx, [][]byte{[]byte("fabric-vpn-packet-smoke")}); err != nil {
+		return false, err
+	}
+	timer := time.NewTimer(3 * time.Second)
+	defer timer.Stop()
+	for {
+		select {
+		case frame := <-pump.Frames():
+			if frame.Type == fabricproto.FrameAck && frame.StreamID == streamID && frame.Sequence == 1 {
+				return true, nil
+			}
+		case err := <-pump.Errors():
+			return false, err
+		case <-timer.C:
+			return false, fmt.Errorf("timed out waiting for fabric vpn packet ack")
+		case <-ctx.Done():
+			return false, ctx.Err()
+		}
+	}
+}
+
 func writeSmokeScopedConfig(local mesh.PeerIdentity, peers map[string]string, routes []mesh.SyntheticRoute) (string, error) {
 	path := filepath.Join(os.TempDir(), "rap-c17e-node-a-scoped-mesh.json")
 	payload, err := json.Marshal(mesh.ScopedSyntheticConfig{
diff --git a/docs/architecture/DISTRIBUTED_FABRIC_NODE_PROTOCOL_PLAN.md b/docs/architecture/DISTRIBUTED_FABRIC_NODE_PROTOCOL_PLAN.md
index 351922f..31e1a4e 100644
--- a/docs/architecture/DISTRIBUTED_FABRIC_NODE_PROTOCOL_PLAN.md
+++ b/docs/architecture/DISTRIBUTED_FABRIC_NODE_PROTOCOL_PLAN.md
@@ -275,6 +275,9 @@ packet delivery can move away from JSON production envelopes in a gated mode.
 `FabricSessionPacketTransport` now adapts that mapper to the existing
 `PacketTransport` interface and can demultiplex inbound DATA frames into the
 VPN packet inbox by stream id.
+`mesh-live-smoke` now sends a real VPN packet batch through
+`FabricSessionPacketTransport` over the WebSocket fabric session and requires a
+stream ACK from the remote node.
 
 Deliverables: