feat(prover): change block signing to use timestamp as key (#466)

.github/workflows/test.yml

@@ -45,7 +45,7 @@ jobs:
         with:
           repository: taikoxyz/taiko-mono
           path: ${{ env.TAIKO_MONO_DIR }}
-          ref: based_contestable_zkrollup_improved
+          ref: based_contestable_zkrollup
 
       - name: Install Foundry
         uses: foundry-rs/foundry-toolchain@v1

prover/db/db.go

@@ -1,11 +1,48 @@
 package db
 
-import "fmt"
+import (
+	"bytes"
+	"math/big"
+	"strconv"
+
+	"github.com/ethereum/go-ethereum/common"
+)
 
 var (
-	BlockKeyPrefix = "blockid-"
+	BlockKeyPrefix = "block-"
 )
 
-func BuildBlockKey(blockID string) []byte {
-	return []byte(fmt.Sprintf("%v%v", BlockKeyPrefix, blockID))
+type SignedBlockData struct {
+	BlockID   *big.Int
+	BlockHash common.Hash
+	Signature string
+}
+
+// BuildBlockKey will build a block key for a signed block
+func BuildBlockKey(blockTimestamp uint64) []byte {
+	return bytes.Join(
+		[][]byte{
+			[]byte(BlockKeyPrefix),
+			[]byte(strconv.Itoa(int(blockTimestamp))),
+		}, []byte{})
+}
+
+// BuildBlockValue will build a block value for a signed block
+func BuildBlockValue(hash []byte, signature []byte, blockID *big.Int) []byte {
+	return bytes.Join(
+		[][]byte{
+			hash,
+			signature,
+			blockID.Bytes(),
+		}, []byte("-"))
+}
+
+func SignedBlockDataFromValue(val []byte) SignedBlockData {
+	v := bytes.Split(val, []byte("-"))
+
+	return SignedBlockData{
+		BlockID:   new(big.Int).SetBytes(v[2]),
+		BlockHash: common.BytesToHash(v[0]),
+		Signature: common.Bytes2Hex(v[1]),
+	}
 }

prover/db/db_test.go

@@ -1,11 +1,35 @@
 package db
 
 import (
+	"bytes"
+	"math/big"
 	"testing"
 
+	"github.com/ethereum/go-ethereum/common"
 	"github.com/stretchr/testify/assert"
 )
 
 func Test_BuildBlockKey(t *testing.T) {
-	assert.Equal(t, BuildBlockKey("1"), []byte("blockid-1"))
+	assert.Equal(t, []byte("block-1"), BuildBlockKey(1))
+}
+
+func Test_BuildBlockValue(t *testing.T) {
+	v := BuildBlockValue([]byte("hash"), []byte("sig"), big.NewInt(1))
+	spl := bytes.Split(v, []byte("-"))
+	assert.Equal(t, "hash", string(spl[0]))
+	assert.Equal(t, "sig", string(spl[1]))
+	assert.Equal(t, uint64(1), new(big.Int).SetBytes(spl[2]).Uint64())
+}
+
+func Test_SignedBlockDataFromValue(t *testing.T) {
+	hash := common.HexToHash("1ada5c5ba58cfca1fbcd4531f4132f8cfef736c2cf40209a1315c489717dfc49")
+	// nolint: lll
+	sig := common.Hex2Bytes("789a80053e4927d0a898db8e065e948f5cf086e32f9ccaa54c1908e22ac430c62621578113ddbb62d509bf6049b8fb544ab06d36f916685a2eb8e57ffadde02301")
+
+	v := BuildBlockValue(hash.Bytes(), sig, big.NewInt(1))
+	data := SignedBlockDataFromValue(v)
+
+	assert.Equal(t, common.Bytes2Hex(sig), data.Signature)
+	assert.Equal(t, hash, data.BlockHash)
+	assert.Equal(t, data.BlockID, big.NewInt(1))
 }

prover/prover.go

@@ -1263,16 +1263,6 @@ func (p *Prover) signBlock(ctx context.Context, blockID *big.Int) error {
 
 	log.Info("guardian prover signing block", "blockID", blockID.Uint64())
 
-	exists, err := p.db.Has(db.BuildBlockKey(blockID.String()))
-	if err != nil {
-		return err
-	}
-
-	if exists {
-		log.Info("guardian prover already signed block", "blockID", blockID.Uint64())
-		return nil
-	}
-
 	latest, err := p.rpc.L2.BlockByNumber(ctx, nil)
 	if err != nil {
 		return err
@@ -1291,22 +1281,34 @@ func (p *Prover) signBlock(ctx context.Context, blockID *big.Int) error {
 		}
 	}
 
-	log.Info("guardian prover block signing caught up",
-		"latestBlock", latest.Number().Uint64(),
-		"eventBlockID", blockID.Uint64(),
-	)
-
 	block, err := p.rpc.L2.BlockByNumber(ctx, blockID)
 	if err != nil {
 		return err
 	}
 
+	exists, err := p.db.Has(db.BuildBlockKey(block.Time()))
+	if err != nil {
+		return err
+	}
+
+	if exists {
+		log.Info("guardian prover already signed block", "blockID", blockID.Uint64())
+		return nil
+	}
+
+	log.Info("guardian prover block signing caught up",
+		"latestBlock", latest.Number().Uint64(),
+		"eventBlockID", blockID.Uint64(),
+	)
+
 	signed, err := crypto.Sign(block.Hash().Bytes(), p.proverPrivateKey)
 	if err != nil {
 		return err
 	}
 
-	if err := p.db.Put(db.BuildBlockKey(blockID.String()), signed); err != nil {
+	val := db.BuildBlockValue(block.Hash().Bytes(), signed, blockID)
+
+	if err := p.db.Put(db.BuildBlockKey(block.Time()), val); err != nil {
 		return err
 	}
 

prover/server/api.go

@@ -1,10 +1,10 @@
 package server
 
 import (
+	"fmt"
 	"math/big"
 	"net/http"
 	"strconv"
-	"strings"
 	"time"
 
 	"github.com/ethereum/go-ethereum/common"
@@ -235,45 +235,61 @@ type SignedBlock struct {
 //	@Success		200	{object} []SignedBlock
 //	@Router			/signedBlocks [get]
 func (srv *ProverServer) GetSignedBlocks(c echo.Context) error {
-	latestBlock, err := srv.rpc.L2.BlockByNumber(c.Request().Context(), nil)
-	if err != nil {
-		if err != nil {
-			log.Error("Failed to get latest L2 block", "error", err)
-			return echo.NewHTTPError(http.StatusInternalServerError, err)
-		}
+	var signedBlocks []SignedBlock = []SignedBlock{}
+
+	// start iterator at at provided timestamp or 0 if not defined
+	start := "0"
+	if c.QueryParam("start") != "" {
+		start = c.QueryParam("start")
 	}
 
-	var signedBlocks []SignedBlock
+	// if no start timestamp was provided, we can get the latest block, and return
+	// defaultNumBlocksToReturn blocks signed before latest, if our guardian prover has signed them.
+	if start == "0" {
+		latestBlock, err := srv.rpc.L2.BlockByNumber(c.Request().Context(), nil)
+		if err != nil {
+			if err != nil {
+				log.Error("Failed to get latest L2 block", "error", err)
+				return echo.NewHTTPError(http.StatusInternalServerError, err)
+			}
+		}
 
-	// start iterator at 0
-	start := big.NewInt(0)
+		// if latestBlock is greater than the number of blocks to return, we only want to return
+		// the most recent N blocks signed by this guardian prover.
+		if latestBlock.NumberU64() > defaultNumBlocksToReturn.Uint64() {
+			blockNum := new(big.Int).Sub(latestBlock.Number(), defaultNumBlocksToReturn)
+			block, err := srv.rpc.L2.BlockByNumber(
+				c.Request().Context(),
+				blockNum,
+			)
+			if err != nil {
+				log.Error("Failed to get L2 block", "error", err, "blockNum", blockNum)
+				return echo.NewHTTPError(http.StatusInternalServerError, err)
+			}
 
-	// if latestBlock is greater than the number of blocks to return, we only want to return
-	// the most recent N blocks signed by this guardian prover.
-	if latestBlock.NumberU64() > numBlocksToReturn.Uint64() {
-		start = new(big.Int).Sub(latestBlock.Number(), numBlocksToReturn)
+			start = strconv.Itoa(int(block.Time()))
+		}
 	}
 
-	iter := srv.db.NewIterator([]byte(db.BlockKeyPrefix), start.Bytes())
+	// start should be set to a block timestamp latestBlock-numBlocksToReturn blocks ago if
+	// a start timestamp was not provided.
+
+	iter := srv.db.NewIterator([]byte(db.BlockKeyPrefix), []byte(start))
 
 	defer iter.Release()
 
 	for iter.Next() {
-		k := strings.Split(string(iter.Key()), "-")
-
-		blockID, err := strconv.Atoi(k[1])
-
-		if err != nil {
-			return echo.NewHTTPError(http.StatusInternalServerError, err)
-		}
+		signedblockData := db.SignedBlockDataFromValue(iter.Value())
 
 		signedBlocks = append(signedBlocks, SignedBlock{
-			BlockID:   uint64(blockID),
-			BlockHash: latestBlock.Hash().Hex(),
-			Signature: common.Bytes2Hex(iter.Value()),
+			BlockID:   signedblockData.BlockID.Uint64(),
+			BlockHash: signedblockData.BlockHash.Hex(),
+			Signature: signedblockData.Signature,
 			Prover:    srv.proverAddress,
 		})
 	}
 
+	fmt.Println("done")
+
 	return c.JSON(http.StatusOK, signedBlocks)
 }

prover/server/api_test.go

@@ -1,9 +1,10 @@
 package server
 
 import (
-	"context"
 	"encoding/json"
+	"fmt"
 	"io"
+	"math/big"
 	"net/http"
 	"strings"
 	"time"
@@ -59,14 +60,26 @@ func (s *ProverServerTestSuite) TestProposeBlockSuccess() {
 }
 
 func (s *ProverServerTestSuite) TestGetSignedBlocks() {
-	latest, err := s.s.rpc.L2.BlockByNumber(context.Background(), nil)
-	s.Nil(err)
+	var start uint64
+	// create 200, we only expect to get 100 back.
+	for i := 0; i < 200; i++ {
+		bigInt := big.NewInt(time.Now().UnixNano())
+		if i == 100 {
+			start = bigInt.Uint64()
+		}
+		signed, err := crypto.Sign(common.BigToHash(bigInt).Bytes(), s.s.proverPrivateKey)
+		s.Nil(err)
+		key := db.BuildBlockKey(bigInt.Uint64())
 
-	signed, err := crypto.Sign(latest.Hash().Bytes(), s.s.proverPrivateKey)
-	s.Nil(err)
+		val := db.BuildBlockValue(common.BigToHash(bigInt).Bytes(), signed, big.NewInt(1))
+
+		s.Nil(s.s.db.Put(key, val))
+		has, err := s.s.db.Has(key)
+		s.Nil(err)
+		s.True(has)
+	}
 
-	s.Nil(s.s.db.Put(db.BuildBlockKey(latest.Number().String()), signed))
-	res := s.sendReq("/signedBlocks")
+	res := s.sendReq(fmt.Sprintf("/signedBlocks?start=%v", start))
 	s.Equal(http.StatusOK, res.StatusCode)
 
 	signedBlocks := make([]SignedBlock, 0)
@@ -76,8 +89,5 @@ func (s *ProverServerTestSuite) TestGetSignedBlocks() {
 	s.Nil(err)
 	s.Nil(json.Unmarshal(b, &signedBlocks))
 
-	s.Equal(1, len(signedBlocks))
-	s.Equal(latest.Hash().Hex(), signedBlocks[0].BlockHash)
-	s.Equal(latest.Number().Uint64(), signedBlocks[0].BlockID)
-	s.Equal(common.Bytes2Hex(signed), signedBlocks[0].Signature)
+	s.Equal(100, len(signedBlocks))
 }

prover/server/server.go

@@ -18,7 +18,7 @@ import (
 )
 
 var (
-	numBlocksToReturn = new(big.Int).SetUint64(200)
+	defaultNumBlocksToReturn = new(big.Int).SetUint64(100)
 )
 
 // @title Taiko Prover API