Add new GetRollupData API to enclave client

go/common/enclave.go

@@ -109,9 +109,12 @@ type Enclave interface {
 	// GetBatch - retrieve a batch if existing within the enclave db.
 	GetBatch(hash L2BatchHash) (*ExtBatch, SystemError)
 
-	// GetBatchBySeqNo - retrieve batch by sequencer number if it's in the db
+	// GetBatchBySeqNo - retrieve batch by sequencer number if it's in the db.
 	GetBatchBySeqNo(seqNo uint64) (*ExtBatch, SystemError)
 
+	// GetRollupData - retrieve the first batch sequence and start time for a given rollup.
+	GetRollupData(hash L2RollupHash) (*PublicRollupMetadata, SystemError)
+
 	// CreateBatch - creates a new head batch extending the previous one for the latest known L1 head if the node is
 	// a sequencer. Will panic otherwise.
 	CreateBatch(skipIfEmpty bool) SystemError

go/common/headers.go

@@ -162,6 +162,12 @@ type CalldataRollupHeader struct {
 	ReOrgs [][]byte `rlp:"optional"` // sparse list of reorged headers - non null only for reorgs.
 }
 
+// PublicRollupMetadata contains internal rollup data that can be requested from the enclave.
+type PublicRollupMetadata struct {
+	FirstBatchSequence *big.Int
+	StartTime          uint64
+}
+
 // MarshalJSON custom marshals the RollupHeader into a json
 func (r *RollupHeader) MarshalJSON() ([]byte, error) {
 	type Alias RollupHeader

go/common/rpc/converters.go

@@ -261,3 +261,29 @@ func FromRollupHeaderMsg(header *generated.RollupHeaderMsg) *common.RollupHeader
 		LastBatchSeqNo:     header.LastBatchSeqNo,
 	}
 }
+
+func ToRollupDataMsg(rollupData *common.PublicRollupMetadata) generated.PublicRollupDataMsg {
+	if rollupData == nil {
+		return generated.PublicRollupDataMsg{}
+	}
+
+	return generated.PublicRollupDataMsg{StartSeq: rollupData.FirstBatchSequence.Uint64(), Timestamp: rollupData.StartTime}
+}
+
+func FromRollupDataMsg(msg *generated.PublicRollupDataMsg) (*common.PublicRollupMetadata, error) {
+	if msg.Timestamp == 0 {
+		return nil, fmt.Errorf("timestamp on the rollup can not be zero")
+	}
+
+	if msg.StartSeq == 0 {
+		return &common.PublicRollupMetadata{
+			FirstBatchSequence: nil,
+			StartTime:          msg.Timestamp,
+		}, nil
+	}
+
+	return &common.PublicRollupMetadata{
+		FirstBatchSequence: big.NewInt(int64(msg.StartSeq)),
+		StartTime:          msg.Timestamp,
+	}, nil
+}