Merge pull request #42 from EspressoSystems/jh/fix

Fix light client reader and add CODEOWNERS

CODEOWNERS

@@ -0,0 +1,5 @@
+# These owners will be the default owners for everything in the repo. Unless a
+# later match takes precedence, they will be requested for review when someone
+# opens a pull request.
+
+*       @nomaxg @ImJeremyHe @sveitser

client/client.go

@@ -27,6 +27,14 @@ func NewClient(url string) *Client {
 	}
 }
 
+func (c *Client) FetchVidCommonByHeight(ctx context.Context, blockHeight uint64) (types.VidCommon, error) {
+	var res types.VidCommonQueryData
+	if err := c.get(ctx, &res, "availability/vid/common/%d", blockHeight); err != nil {
+		return types.VidCommon{}, err
+	}
+	return res.Common, nil
+}
+
 func (c *Client) FetchLatestBlockHeight(ctx context.Context) (uint64, error) {
 	var res uint64
 	if err := c.get(ctx, &res, "status/block-height"); err != nil {
@@ -65,9 +73,7 @@ func (c *Client) FetchTransactionsInBlock(ctx context.Context, blockHeight uint6
 	if err := c.get(ctx, &res, "availability/block/%d/namespace/%d", blockHeight, namespace); err != nil {
 		return TransactionsInBlock{}, err
 	}
-	if res.Proof == nil {
-		return TransactionsInBlock{}, fmt.Errorf("field proof of type NamespaceResponse is required")
-	}
+
 	if res.Transactions == nil {
 		return TransactionsInBlock{}, fmt.Errorf("field transactions of type NamespaceResponse is required")
 	}
@@ -81,9 +87,23 @@ func (c *Client) FetchTransactionsInBlock(ctx context.Context, blockHeight uint6
 		txs = append(txs, tx.Payload)
 	}
 
+	if len(txs) > 0 && res.Proof == nil {
+		return TransactionsInBlock{}, fmt.Errorf("field proof of type NamespaceResponse is required")
+	}
+
+	if res.Proof == nil {
+		return TransactionsInBlock{}, nil
+	}
+
+	vidCommon, err := c.FetchVidCommonByHeight(ctx, blockHeight)
+	if err != nil {
+		return TransactionsInBlock{}, err
+	}
+
 	return TransactionsInBlock{
 		Transactions: txs,
 		Proof:        *res.Proof,
+		VidCommon:    vidCommon,
 	}, nil
 
 }

client/query.go

@@ -26,7 +26,8 @@ type TransactionsInBlock struct {
 	// The transactions.
 	Transactions []types.Bytes `json:"transactions"`
 	// A proof that these are all the transactions in the block with the requested namespace.
-	Proof types.NamespaceProof `json:"proof"`
+	Proof     types.NamespaceProof `json:"proof"`
+	VidCommon types.VidCommon      `json:"vidCommon"`
 }
 
 func (t *TransactionsInBlock) UnmarshalJSON(b []byte) error {

light-client/light_client_reader.go

@@ -3,19 +3,19 @@ package lightclient
 import (
 	"context"
 	"math/big"
-	"time"
 
 	"github.com/EspressoSystems/espresso-sequencer-go/types"
 	"github.com/ethereum/go-ethereum/accounts/abi/bind"
 	"github.com/ethereum/go-ethereum/common"
 )
 
+var _ LightClientReaderInterface = (*LightClientReader)(nil)
+
 type LightClientReaderInterface interface {
 	ValidatedHeight() (validatedHeight uint64, l1Height uint64, err error)
-	FetchMerkleRoot(hotShotHeight uint64, opts bind.CallOpts) (types.BlockMerkleSnapshot, error)
+	FetchMerkleRoot(hotShotHeight uint64, opts *bind.CallOpts) (types.BlockMerkleSnapshot, error)
 
-	// A mock function for now
-	IsHotShotAvailable(maxDriftTime time.Duration) bool
+	IsHotShotLive(delayThreshold uint64) (bool, error)
 }
 
 type LightClientReader struct {
@@ -67,6 +67,11 @@ func (l *LightClientReader) FetchMerkleRoot(hotShotHeight uint64, opts *bind.Cal
 	}, nil
 }
 
-func (l *LightClientReader) IsHotShotAvailable(t time.Duration) bool {
-	return true
+func (l *LightClientReader) IsHotShotLive(delayThreshold uint64) (bool, error) {
+	header, err := l.L1Client.HeaderByNumber(context.Background(), nil)
+	if err != nil {
+		return false, err
+	}
+	threshold := new(big.Int).SetUint64(delayThreshold)
+	return l.LightClient.LagOverEscapeHatchThreshold(&bind.CallOpts{}, header.Number, threshold)
 }

types/types.go

@@ -13,6 +13,15 @@ import (
 
 type TaggedBase64 = tagged_base64.TaggedBase64
 
+type VidCommon = json.RawMessage
+
+type VidCommonQueryData struct {
+	Height      uint64        `json:"height"`
+	BlockHash   *TaggedBase64 `json:"block_hash"`
+	PayloadHash *TaggedBase64 `json:"payload_hash"`
+	Common      VidCommon     `json:"common"`
+}
+
 type Header struct {
 	ChainConfig         *ResolvableChainConfig `json:"chain_config"`
 	Height              uint64                 `json:"height"`