feat(node): add halt_height config field for coordinated chain upgrades

tm2/pkg/bft/config/config.go

@@ -324,6 +324,10 @@ type BaseConfig struct {
 
 	// TCP or UNIX socket address for the profiling server to listen on
 	ProfListenAddress string `toml:"prof_laddr" comment:"TCP or UNIX socket address for the profiling server to listen on"`
+
+	// If non-zero, the node will halt after committing this block height.
+	// Useful for coordinated chain upgrades.
+	HaltHeight int64 `toml:"halt_height" comment:"If non-zero, the node will halt after committing this block height.\n Useful for coordinated chain upgrades."`
 }
 
 // DefaultBaseConfig returns a default base configuration for a Tendermint node

tm2/pkg/bft/consensus/state.go

@@ -138,6 +138,9 @@ type ConsensusState struct {
 	doPrevote      func(height int64, round int)
 	setProposal    func(proposal *types.Proposal) error
 
+	// if non-zero, the node will stop after committing this height
+	haltHeight int64
+
 	// closed when we finish shutting down
 	done chan struct{}
 }
@@ -195,6 +198,12 @@ func (cs *ConsensusState) SetLogger(l *slog.Logger) {
 	cs.timeoutTicker.SetLogger(l)
 }
 
+// SetHaltHeight sets the height at which the node will stop after committing.
+// If set to 0, the node runs indefinitely.
+func (cs *ConsensusState) SetHaltHeight(height int64) {
+	cs.haltHeight = height
+}
+
 // SetEventSwitch sets event bus.
 func (cs *ConsensusState) SetEventSwitch(evsw events.EventSwitch) {
 	cs.evsw = evsw
@@ -1402,6 +1411,14 @@ func (cs *ConsensusState) finalizeCommit(height int64) {
 
 	// Log the telemetry
 	cs.logTelemetry(block)
+
+	// Check if we should halt at this height
+	if cs.haltHeight > 0 && height >= cs.haltHeight {
+		cs.Logger.Info("Halt height reached, shutting down", "height", height, "halt_height", cs.haltHeight)
+		if err := osm.Kill(); err != nil {
+			cs.Logger.Error("Failed to halt node", "err", err)
+		}
+	}
 }
 
 // -----------------------------------------------------------------------------

tm2/pkg/bft/consensus/state_test.go

@@ -1807,3 +1807,26 @@ func TestStateOutputVoteStats(t *testing.T) {
 func subscribe(evsw events.EventSwitch, protoevent events.Event) <-chan events.Event {
 	return events.SubscribeToEvent(evsw, testSubscriber, protoevent)
 }
+
+func TestSetHaltHeight(t *testing.T) {
+	t.Helper()
+
+	cs := &ConsensusState{}
+
+	// Default should be 0 (no halt)
+	if cs.haltHeight != 0 {
+		t.Fatalf("expected default haltHeight to be 0, got %d", cs.haltHeight)
+	}
+
+	// Set halt height
+	cs.SetHaltHeight(100)
+	if cs.haltHeight != 100 {
+		t.Fatalf("expected haltHeight to be 100, got %d", cs.haltHeight)
+	}
+
+	// Set to 0 to disable
+	cs.SetHaltHeight(0)
+	if cs.haltHeight != 0 {
+		t.Fatalf("expected haltHeight to be 0, got %d", cs.haltHeight)
+	}
+}

tm2/pkg/bft/node/node.go

@@ -577,6 +577,12 @@ func NewNode(config *cfg.Config,
 		option(node)
 	}
 
+	// Apply halt height from config
+	if config.BaseConfig.HaltHeight > 0 {
+		node.consensusState.SetHaltHeight(config.BaseConfig.HaltHeight)
+		logger.Info("Halt height configured", "height", config.BaseConfig.HaltHeight)
+	}
+
 	return node, nil
 }