go/control: Show local checkpoint heights

.changelog/5265.feature.md

@@ -0,0 +1,6 @@
+go/oasis-node: Display consensus checkpoint heights
+
+A new field `heights` has been added to the `oasis-node control status` output
+under the `consensus.checkpoint` status section. If checkpointer is not
+disabled and there is at least one checkpoint, this field displays a list
+of local checkpoint heights.

go/consensus/api/api.go

@@ -375,6 +375,9 @@ type Status struct {
 
 	// P2P is the P2P status of the node.
 	P2P *P2PStatus `json:"p2p,omitempty"`
+
+	// Checkpoint is the checkpoints status of the node.
+	Checkpoint *CheckpointStatus `json:"checkpoint,omitempty"`
 }
 
 // P2PStatus is the P2P status of a node.
@@ -392,6 +395,14 @@ type P2PStatus struct {
 	Peers []string `json:"peers"`
 }
 
+// CheckpointStatus is the checkpoints status of the node.
+type CheckpointStatus struct {
+	// Heights is a list of consensus heights for which the node has checkpoints locally.
+	//
+	// Heights are sorted in descending order.
+	Heights []uint64 `json:"heights"`
+}
+
 // Service is an interface that a consensus backend service must provide.
 type Service interface {
 	service.BackgroundService

go/consensus/cometbft/full/common.go

@@ -3,6 +3,7 @@ package full
 import (
 	"context"
 	"fmt"
+	"slices"
 	"sync"
 	"sync/atomic"
 
@@ -831,19 +832,47 @@ func (n *commonNode) GetStatus(ctx context.Context) (*consensusAPI.Status, error
 			valSetHeight = status.GenesisHeight
 		}
 		vals, err := n.stateStore.LoadValidators(valSetHeight)
-		if err != nil {
-			// Failed to load validator set.
-			status.IsValidator = false
-		} else {
+		switch err {
+		case nil:
 			consensusPk := n.identity.ConsensusSigner.Public()
 			consensusAddr := []byte(crypto.PublicKeyToCometBFT(&consensusPk).Address())
 			status.IsValidator = vals.HasAddress(consensusAddr)
+		default:
+			// Failed to load validator set.
+			status.IsValidator = false
+		}
+
+		if n.Checkpointer() != nil {
+			status.Checkpoint = n.fetchCheckpointStatus(ctx)
 		}
 	}
 
 	return status, nil
 }
 
+// fetchCheckpointStatus fetches checkpoint status.
+//
+// In case of zero checkpoints or error a nil status is returned.
+func (n *commonNode) fetchCheckpointStatus(ctx context.Context) *consensusAPI.CheckpointStatus {
+	cps, err := n.mux.State().Storage().GetCheckpoints(ctx, &checkpoint.GetCheckpointsRequest{
+		Version: 1,
+	})
+	if err != nil {
+		n.Logger.Error("failed to fetch checkpoints status", "err", err)
+		return nil
+	}
+	var heights []uint64
+	for _, cp := range cps {
+		heights = append(heights, cp.Root.Version)
+	}
+	if len(heights) <= 0 {
+		return nil
+	}
+	slices.Sort(heights)
+	slices.Reverse(heights)
+	return &consensusAPI.CheckpointStatus{Heights: heights}
+}
+
 // Unimplemented methods.
 
 // Implements consensusAPI.Backend.