From 8feb6d58fe57220c69c1925899c3d1f175fa243b Mon Sep 17 00:00:00 2001
From: Mikhail <misha_mst@mail.ru>
Date: Sat, 16 May 2026 12:50:51 +0300
Subject: [PATCH] Report QUIC capacity in smoke

---
 .../cmd/mesh-live-smoke/main.go               | 26 ++++++++++++-------
 .../DISTRIBUTED_FABRIC_NODE_PROTOCOL_PLAN.md  |  2 ++
 2 files changed, 18 insertions(+), 10 deletions(-)

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 5bb811a..6ed3319 100644
--- a/agents/rap-node-agent/cmd/mesh-live-smoke/main.go
+++ b/agents/rap-node-agent/cmd/mesh-live-smoke/main.go
@@ -45,6 +45,7 @@ type smokeReport struct {
 	FabricVPNPacketFanout   int            `json:"fabric_vpn_packet_fanout"`
 	FabricQUICAccepted      bool           `json:"fabric_quic_accepted"`
 	FabricQUICEndpoint      string         `json:"fabric_quic_endpoint"`
+	FabricQUICPressure      int            `json:"fabric_quic_capacity_pressure_percent"`
 	FabricSessionLatencyMS  int64          `json:"fabric_session_latency_ms"`
 	FabricSessionEndpoint   string         `json:"fabric_session_endpoint"`
 	PeerEndpoints           map[string]any `json:"peer_endpoints"`
@@ -145,7 +146,7 @@ func run(ctx context.Context) (smokeReport, error) {
 	if err != nil {
 		return smokeReport{}, fmt.Errorf("fabric vpn packet session smoke: %w", err)
 	}
-	fabricQUICAccepted, fabricQUICEndpoint, err := smokeQUICFabricSession(ctx)
+	fabricQUICAccepted, fabricQUICEndpoint, fabricQUICPressure, err := smokeQUICFabricSession(ctx)
 	if err != nil {
 		return smokeReport{}, fmt.Errorf("fabric quic smoke: %w", err)
 	}
@@ -167,6 +168,7 @@ func run(ctx context.Context) (smokeReport, error) {
 		FabricVPNPacketFanout:   fabricVPNPacketFanout,
 		FabricQUICAccepted:      fabricQUICAccepted,
 		FabricQUICEndpoint:      fabricQUICEndpoint,
+		FabricQUICPressure:      fabricQUICPressure,
 		FabricSessionLatencyMS:  fabricSessionLatency.Milliseconds(),
 		FabricSessionEndpoint:   nodeB.URL + "/mesh/v1/fabric/session/ws",
 		PeerEndpoints: map[string]any{
@@ -177,17 +179,20 @@ func run(ctx context.Context) (smokeReport, error) {
 	}, nil
 }
 
-func smokeQUICFabricSession(ctx context.Context) (bool, string, error) {
+func smokeQUICFabricSession(ctx context.Context) (bool, string, int, error) {
 	server, err := mesh.StartQUICFabricServer(ctx, mesh.QUICFabricServerConfig{
 		ListenAddr: "127.0.0.1:0",
 		TLSConfig:  smokeQUICTLSConfig(),
 	})
 	if err != nil {
-		return false, "", err
+		return false, "", 0, err
 	}
 	defer server.Close()
 	endpoint := server.Addr().String()
-	session, err := mesh.NewQUICFabricTransport(nil).Connect(ctx, mesh.FabricTransportTarget{
+	transport := mesh.NewQUICFabricTransport(nil)
+	defer transport.Close()
+	session, err := transport.Connect(ctx, mesh.FabricTransportTarget{
+		PeerID:   "node-b",
 		Endpoint: endpoint,
 		TLSConfig: &tls.Config{
 			InsecureSkipVerify: true,
@@ -198,7 +203,7 @@ func smokeQUICFabricSession(ctx context.Context) (bool, string, error) {
 		ErrorBuffer:   4,
 	})
 	if err != nil {
-		return false, endpoint, err
+		return false, endpoint, 0, err
 	}
 	defer session.Close()
 	if err := session.Send(ctx, fabricproto.Frame{
@@ -206,20 +211,21 @@ func smokeQUICFabricSession(ctx context.Context) (bool, string, error) {
 		Sequence: uint64(time.Now().UnixNano()),
 		Payload:  []byte("mesh-live-smoke-quic"),
 	}); err != nil {
-		return false, endpoint, err
+		return false, endpoint, 0, err
 	}
 	timer := time.NewTimer(3 * time.Second)
 	defer timer.Stop()
 	for {
 		select {
 		case frame := <-session.Frames():
-			return frame.Type == fabricproto.FramePong && string(frame.Payload) == "mesh-live-smoke-quic", endpoint, nil
+			snapshot := transport.Snapshot()
+			return frame.Type == fabricproto.FramePong && string(frame.Payload) == "mesh-live-smoke-quic", endpoint, snapshot.CapacityPressurePercent, nil
 		case err := <-session.Errors():
-			return false, endpoint, err
+			return false, endpoint, 0, err
 		case <-timer.C:
-			return false, endpoint, fmt.Errorf("timed out waiting for quic pong")
+			return false, endpoint, 0, fmt.Errorf("timed out waiting for quic pong")
 		case <-ctx.Done():
-			return false, endpoint, ctx.Err()
+			return false, endpoint, 0, ctx.Err()
 		}
 	}
 }
diff --git a/docs/architecture/DISTRIBUTED_FABRIC_NODE_PROTOCOL_PLAN.md b/docs/architecture/DISTRIBUTED_FABRIC_NODE_PROTOCOL_PLAN.md
index defa487..18d0253 100644
--- a/docs/architecture/DISTRIBUTED_FABRIC_NODE_PROTOCOL_PLAN.md
+++ b/docs/architecture/DISTRIBUTED_FABRIC_NODE_PROTOCOL_PLAN.md
@@ -421,6 +421,8 @@ connection count, and capacity pressure percentage next to stream limit rejects.
 Closed cached QUIC connections discovered during snapshot generation now update
 the transport's cumulative eviction counters, keeping successive heartbeats
 consistent.
+`mesh-live-smoke` reports QUIC fabric capacity-pressure percentage from the
+transport snapshot, verifying that the capacity fields are populated.
 Endpoint ranking treats `capacity_limited` observations as a soft pressure
 penalty instead of a hard recent failure, enabling load spreading without
 marking the carrier unhealthy.