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 +162,24 @@ 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
+}
+
+func (r *PublicRollupMetadata) Encoded() ([]byte, error) {
+	return rlp.EncodeToBytes(r)
+}
+
+func DecodePublicRollupMetadata(encoded []byte) (*PublicRollupMetadata, error) {
+	var rollupMetadata PublicRollupMetadata
+	if err := rlp.DecodeBytes(encoded, &rollupMetadata); err != nil {
+		return nil, err
+	}
+	return &rollupMetadata, nil
+}
+
 // MarshalJSON custom marshals the RollupHeader into a json
 func (r *RollupHeader) MarshalJSON() ([]byte, error) {
 	type Alias RollupHeader