op-program: Implement caching for the L1 oracle.

op-program/client/l1/cache.go

+package l1
+
+import (
+	"github.com/ethereum-optimism/optimism/op-node/eth"
+	"github.com/ethereum/go-ethereum/common"
+	"github.com/ethereum/go-ethereum/core/types"
+)
+
+// CachingOracle is an implementation of Oracle that delegates to another implementation, adding caching of all results
+type CachingOracle struct {
+	oracle Oracle
+	blocks map[common.Hash]eth.BlockInfo
+	txs    map[common.Hash]types.Transactions
+	rcpts  map[common.Hash]types.Receipts
+}
+
+func NewCachingOracle(oracle Oracle) *CachingOracle {
+	return &CachingOracle{
+		oracle: oracle,
+		blocks: make(map[common.Hash]eth.BlockInfo),
+		txs:    make(map[common.Hash]types.Transactions),
+		rcpts:  make(map[common.Hash]types.Receipts),
+	}
+}
+
+func (o CachingOracle) HeaderByBlockHash(blockHash common.Hash) eth.BlockInfo {
+	block, ok := o.blocks[blockHash]
+	if ok {
+		return block
+	}
+	block = o.oracle.HeaderByBlockHash(blockHash)
+	o.blocks[blockHash] = block
+	return block
+}
+
+func (o CachingOracle) TransactionsByBlockHash(blockHash common.Hash) (eth.BlockInfo, types.Transactions) {
+	txs, ok := o.txs[blockHash]
+	if ok {
+		return o.HeaderByBlockHash(blockHash), txs
+	}
+	block, txs := o.oracle.TransactionsByBlockHash(blockHash)
+	o.blocks[blockHash] = block
+	o.txs[blockHash] = txs
+	return block, txs
+}
+
+func (o CachingOracle) ReceiptsByBlockHash(blockHash common.Hash) (eth.BlockInfo, types.Receipts) {
+	rcpts, ok := o.rcpts[blockHash]
+	if ok {
+		return o.HeaderByBlockHash(blockHash), rcpts
+	}
+	block, rcpts := o.oracle.ReceiptsByBlockHash(blockHash)
+	o.blocks[blockHash] = block
+	o.rcpts[blockHash] = rcpts
+	return block, rcpts
+}

op-program/client/l1/cache_test.go

+package l1
+
+import (
+	"math/rand"
+	"testing"
+
+	"github.com/ethereum-optimism/optimism/op-node/testutils"
+	"github.com/stretchr/testify/require"
+)
+
+// Should implement Oracle
+var _ Oracle = (*CachingOracle)(nil)
+
+func TestCachingOracle_HeaderByBlockHash(t *testing.T) {
+	rng := rand.New(rand.NewSource(1))
+	stub := newStubOracle(t)
+	oracle := NewCachingOracle(stub)
+	block := testutils.RandomBlockInfo(rng)
+
+	// Initial call retrieves from the stub
+	stub.blocks[block.Hash()] = block
+	result := oracle.HeaderByBlockHash(block.Hash())
+	require.Equal(t, block, result)
+
+	// Later calls should retrieve from cache
+	delete(stub.blocks, block.Hash())
+	result = oracle.HeaderByBlockHash(block.Hash())
+	require.Equal(t, block, result)
+}
+
+func TestCachingOracle_TransactionsByBlockHash(t *testing.T) {
+	rng := rand.New(rand.NewSource(1))
+	stub := newStubOracle(t)
+	oracle := NewCachingOracle(stub)
+	block, _ := testutils.RandomBlock(rng, 3)
+
+	// Initial call retrieves from the stub
+	stub.blocks[block.Hash()] = block
+	stub.txs[block.Hash()] = block.Transactions()
+	actualBlock, actualTxs := oracle.TransactionsByBlockHash(block.Hash())
+	require.Equal(t, block, actualBlock)
+	require.Equal(t, block.Transactions(), actualTxs)
+
+	// Later calls should retrieve from cache
+	delete(stub.blocks, block.Hash())
+	delete(stub.txs, block.Hash())
+	actualBlock, actualTxs = oracle.TransactionsByBlockHash(block.Hash())
+	require.Equal(t, block, actualBlock)
+	require.Equal(t, block.Transactions(), actualTxs)
+}
+
+func TestCachingOracle_ReceiptsByBlockHash(t *testing.T) {
+	rng := rand.New(rand.NewSource(1))
+	stub := newStubOracle(t)
+	oracle := NewCachingOracle(stub)
+	block, rcpts := testutils.RandomBlock(rng, 3)
+
+	// Initial call retrieves from the stub
+	stub.blocks[block.Hash()] = block
+	stub.rcpts[block.Hash()] = rcpts
+	actualBlock, actualRcpts := oracle.ReceiptsByBlockHash(block.Hash())
+	require.Equal(t, block, actualBlock)
+	require.EqualValues(t, rcpts, actualRcpts)
+
+	// Later calls should retrieve from cache
+	delete(stub.blocks, block.Hash())
+	delete(stub.rcpts, block.Hash())
+	actualBlock, actualRcpts = oracle.ReceiptsByBlockHash(block.Hash())
+	require.Equal(t, block, actualBlock)
+	require.EqualValues(t, rcpts, actualRcpts)
+}

op-program/client/l1/client_test.go

@@ -145,54 +145,12 @@ func TestL1BlockRefByNumber(t *testing.T) {
 }
 
 func newClient(t *testing.T) (*OracleL1Client, *stubOracle) {
-	stub := &stubOracle{
-		t:      t,
-		blocks: make(map[common.Hash]eth.BlockInfo),
-		txs:    make(map[common.Hash]types.Transactions),
-		rcpts:  make(map[common.Hash]types.Receipts),
-	}
+	stub := newStubOracle(t)
 	stub.blocks[head.Hash()] = head
 	client := NewOracleL1Client(testlog.Logger(t, log.LvlDebug), stub, head.Hash())
 	return client, stub
 }
 
-type stubOracle struct {
-	t *testing.T
-
-	// blocks maps block hash to eth.BlockInfo
-	blocks map[common.Hash]eth.BlockInfo
-
-	// txs maps block hash to transactions
-	txs map[common.Hash]types.Transactions
-
-	// rcpts maps Block hash to receipts
-	rcpts map[common.Hash]types.Receipts
-}
-
-func (o stubOracle) HeaderByBlockHash(blockHash common.Hash) eth.BlockInfo {
-	info, ok := o.blocks[blockHash]
-	if !ok {
-		o.t.Fatalf("unknown block %s", blockHash)
-	}
-	return info
-}
-
-func (o stubOracle) TransactionsByBlockHash(blockHash common.Hash) (eth.BlockInfo, types.Transactions) {
-	txs, ok := o.txs[blockHash]
-	if !ok {
-		o.t.Fatalf("unknown txs %s", blockHash)
-	}
-	return o.HeaderByBlockHash(blockHash), txs
-}
-
-func (o stubOracle) ReceiptsByBlockHash(blockHash common.Hash) (eth.BlockInfo, types.Receipts) {
-	rcpts, ok := o.rcpts[blockHash]
-	if !ok {
-		o.t.Fatalf("unknown rcpts %s", blockHash)
-	}
-	return o.HeaderByBlockHash(blockHash), rcpts
-}
-
 func blockNum(num uint64) eth.BlockInfo {
 	parentNum := num - 1
 	return &testutils.MockBlockInfo{

op-program/client/l1/stub_oracle_test.go

+package l1
+
+import (
+	"testing"
+
+	"github.com/ethereum-optimism/optimism/op-node/eth"
+	"github.com/ethereum/go-ethereum/common"
+	"github.com/ethereum/go-ethereum/core/types"
+)
+
+type stubOracle struct {
+	t *testing.T
+
+	// blocks maps block hash to eth.BlockInfo
+	blocks map[common.Hash]eth.BlockInfo
+
+	// txs maps block hash to transactions
+	txs map[common.Hash]types.Transactions
+
+	// rcpts maps Block hash to receipts
+	rcpts map[common.Hash]types.Receipts
+}
+
+func newStubOracle(t *testing.T) *stubOracle {
+	return &stubOracle{
+		t:      t,
+		blocks: make(map[common.Hash]eth.BlockInfo),
+		txs:    make(map[common.Hash]types.Transactions),
+		rcpts:  make(map[common.Hash]types.Receipts),
+	}
+}
+func (o stubOracle) HeaderByBlockHash(blockHash common.Hash) eth.BlockInfo {
+	info, ok := o.blocks[blockHash]
+	if !ok {
+		o.t.Fatalf("unknown block %s", blockHash)
+	}
+	return info
+}
+
+func (o stubOracle) TransactionsByBlockHash(blockHash common.Hash) (eth.BlockInfo, types.Transactions) {
+	txs, ok := o.txs[blockHash]
+	if !ok {
+		o.t.Fatalf("unknown txs %s", blockHash)
+	}
+	return o.HeaderByBlockHash(blockHash), txs
+}
+
+func (o stubOracle) ReceiptsByBlockHash(blockHash common.Hash) (eth.BlockInfo, types.Receipts) {
+	rcpts, ok := o.rcpts[blockHash]
+	if !ok {
+		o.t.Fatalf("unknown rcpts %s", blockHash)
+	}
+	return o.HeaderByBlockHash(blockHash), rcpts
+}

op-program/host/l1/l1.go

@@ -21,6 +21,6 @@ func NewFetchingL1(ctx context.Context, logger log.Logger, cfg *config.Config) (
 	if err != nil {
 		return nil, err
 	}
-	oracle := NewFetchingL1Oracle(ctx, logger, source)
+	oracle := cll1.NewCachingOracle(NewFetchingL1Oracle(ctx, logger, source))
 	return cll1.NewOracleL1Client(logger, oracle, cfg.L1Head), err
 }