The controller raises what the watchman says stopped moving, and takes a machine's silence from its presence (issue 1156)

cmd/mesh-controller/watchdogs.go

@@ -155,6 +155,8 @@ type machineFacts struct {
 	tools      bool
 	toolsHeard time.Time
 	toolsEvery time.Duration
+	// presence is the watchman's word on whether it is online (novox/hq ADR 0433 §3); unsaid, the heartbeat rule judges.
+	presence presenceVerdict
 }
 
 // asleep says the machine said it would be away and has not said it is back (ADR 0211).
@@ -470,7 +472,7 @@ func (w *watchdogs) gatherMachines(ctx context.Context, inv *inventory.Inventory
 			}
 			m.reportedCurrent = r.Current
 		}
-		if !m.lastHeard.IsZero() && now.Sub(m.lastHeard) > heartbeatBound(m.every) {
+		if m.silent(now) {
 			anyPast = true
 		}
 		if m.tools && now.Sub(later(m.toolsHeard, link.ToolsBeats.Started())) > heartbeatBound(m.toolsEvery) {
@@ -478,6 +480,19 @@ func (w *watchdogs) gatherMachines(ctx context.Context, inv *inventory.Inventory
 		}
 		out = append(out, m)
 	}
+	// What the watchman says of each machine: its stuck presence key is the silent verdict, and presence.<node>'s time when
+	// it was last heard (ADR 0433 §3). Unreadable is said, and the heartbeat rule judges as before.
+	if w.js != nil {
+		if err := withPresence(ctx, w.js.Conn(), out); err != nil {
+			fmt.Printf("what the watchman says of the machines' presence cannot be read: %v\n", err)
+		} else {
+			for _, m := range out {
+				if m.silent(now) {
+					anyPast = true
+				}
+			}
+		}
+	}
 	// What a machine past its bound last said of its power, read only then: a machine that said it
 	// is asleep is not lost (ADR 0211). Unreadable is said: a sleeping laptop is then called silent,
 	// which is the louder mistake and the right one to make.