all: derive log fields only after filtering

accounts/abi/bind/backends/simulated.go

@@ -850,6 +850,10 @@ func (fb *filterBackend) GetLogs(ctx context.Context, hash common.Hash) ([][]*ty
 	return logs, nil
 }
 
+func (fb *filterBackend) GetLogsFiltered(ctx context.Context, hash common.Hash, _ func([]*types.Log) []*types.Log) ([]*types.Log, error) {
+	panic("unimplemented")
+}
+
 func (fb *filterBackend) SubscribeNewTxsEvent(ch chan<- core.NewTxsEvent) event.Subscription {
 	return nullSubscription()
 }

core/rawdb/accessors_chain.go

@@ -716,7 +716,7 @@ func deriveLogFields(receipts []*receiptLogs, hash common.Hash, number uint64, t
 // ReadLogs retrieves the logs for all transactions in a block. The log fields
 // are populated with metadata. In case the receipts or the block body
 // are not found, a nil is returned.
-func ReadLogs(db ethdb.Reader, hash common.Hash, number uint64) [][]*types.Log {
+func ReadLogs(db ethdb.Reader, hash common.Hash, number uint64, fn func([]*types.Log) []*types.Log) []*types.Log {
 	// Retrieve the flattened receipt slice
 	data := ReadReceiptsRLP(db, hash, number)
 	if len(data) == 0 {
@@ -727,21 +727,36 @@ func ReadLogs(db ethdb.Reader, hash common.Hash, number uint64) [][]*types.Log {
 		log.Error("Invalid receipt array RLP", "hash", hash, "err", err)
 		return nil
 	}
-
-	body := ReadBody(db, hash, number)
-	if body == nil {
-		log.Error("Missing body but have receipt", "hash", hash, "number", number)
-		return nil
-	}
-	if err := deriveLogFields(receipts, hash, number, body.Transactions); err != nil {
-		log.Error("Failed to derive block receipts fields", "hash", hash, "number", number, "err", err)
-		return nil
-	}
 	logs := make([][]*types.Log, len(receipts))
+	id := uint(0)
 	for i, receipt := range receipts {
 		logs[i] = receipt.Logs
+		for _, log := range logs[i] {
+			log.TxIndex = uint(i)
+			log.Index = id
+			id++
+		}
+	}
+	var flatLogs []*types.Log
+	for _, l := range logs {
+		flatLogs = append(flatLogs, l...)
+	}
+	filtered := fn(flatLogs)
+	if len(filtered) > 0 {
+		body := ReadBody(db, hash, number)
+		if body == nil {
+			log.Error("Missing body but have receipt", "hash", hash, "number", number)
+			return nil
+		}
+		for _, log := range filtered {
+			log.BlockNumber = number
+			log.BlockHash = hash
+			log.TxHash = body.Transactions[log.TxIndex].Hash()
+		}
+		return filtered
+	} else {
+		return []*types.Log{}
 	}
-	return logs
 }
 
 // ReadBlock retrieves an entire block corresponding to the hash, assembling it

core/rawdb/accessors_chain_test.go

@@ -744,30 +744,26 @@ func TestReadLogs(t *testing.T) {
 	// Insert the receipt slice into the database and check presence
 	WriteReceipts(db, hash, 0, receipts)
 
-	logs := ReadLogs(db, hash, 0)
+	logs := ReadLogs(db, hash, 0, func(logs []*types.Log) []*types.Log { return logs })
 	if len(logs) == 0 {
 		t.Fatalf("no logs returned")
 	}
-	if have, want := len(logs), 2; have != want {
+	if have, want := len(logs), 4; have != want {
 		t.Fatalf("unexpected number of logs returned, have %d want %d", have, want)
 	}
-	if have, want := len(logs[0]), 2; have != want {
-		t.Fatalf("unexpected number of logs[0] returned, have %d want %d", have, want)
-	}
-	if have, want := len(logs[1]), 2; have != want {
-		t.Fatalf("unexpected number of logs[1] returned, have %d want %d", have, want)
-	}
 
 	// Fill in log fields so we can compare their rlp encoding
 	if err := types.Receipts(receipts).DeriveFields(params.TestChainConfig, hash, 0, body.Transactions); err != nil {
 		t.Fatal(err)
 	}
+	idx := 0
 	for i, pr := range receipts {
-		for j, pl := range pr.Logs {
-			rlpHave, err := rlp.EncodeToBytes(newFullLogRLP(logs[i][j]))
+		for _, pl := range pr.Logs {
+			rlpHave, err := rlp.EncodeToBytes(newFullLogRLP(logs[idx]))
 			if err != nil {
 				t.Fatal(err)
 			}
+			idx++
 			rlpWant, err := rlp.EncodeToBytes(newFullLogRLP(pl))
 			if err != nil {
 				t.Fatal(err)

eth/api_backend.go

@@ -181,12 +181,24 @@ func (b *EthAPIBackend) GetReceipts(ctx context.Context, hash common.Hash) (type
 }
 
 func (b *EthAPIBackend) GetLogs(ctx context.Context, hash common.Hash) ([][]*types.Log, error) {
+	receipts := b.eth.blockchain.GetReceiptsByHash(hash)
+	if receipts == nil {
+		return nil, nil
+	}
+	logs := make([][]*types.Log, len(receipts))
+	for i, receipt := range receipts {
+		logs[i] = receipt.Logs
+	}
+	return logs, nil
+}
+
+func (b *EthAPIBackend) GetLogsFiltered(ctx context.Context, hash common.Hash, filterFn func([]*types.Log) []*types.Log) ([]*types.Log, error) {
 	db := b.eth.ChainDb()
 	number := rawdb.ReadHeaderNumber(db, hash)
 	if number == nil {
 		return nil, errors.New("failed to get block number from hash")
 	}
-	logs := rawdb.ReadLogs(db, hash, *number)
+	logs := rawdb.ReadLogs(db, hash, *number, filterFn)
 	if logs == nil {
 		return nil, errors.New("failed to get logs for block")
 	}

eth/filters/filter.go

@@ -36,6 +36,7 @@ type Backend interface {
 	HeaderByHash(ctx context.Context, blockHash common.Hash) (*types.Header, error)
 	GetReceipts(ctx context.Context, blockHash common.Hash) (types.Receipts, error)
 	GetLogs(ctx context.Context, blockHash common.Hash) ([][]*types.Log, error)
+	GetLogsFiltered(ctx context.Context, blockHash common.Hash, fn func([]*types.Log) []*types.Log) ([]*types.Log, error)
 
 	SubscribeNewTxsEvent(chan<- core.NewTxsEvent) event.Subscription
 	SubscribeChainEvent(ch chan<- core.ChainEvent) event.Subscription
@@ -244,24 +245,22 @@ func (f *Filter) blockLogs(ctx context.Context, header *types.Header) (logs []*t
 // checkMatches checks if the receipts belonging to the given header contain any log events that
 // match the filter criteria. This function is called when the bloom filter signals a potential match.
 func (f *Filter) checkMatches(ctx context.Context, header *types.Header) (logs []*types.Log, err error) {
+	filterFn := func(unfiltered []*types.Log) []*types.Log {
+		return filterLogs(unfiltered, nil, nil, f.addresses, f.topics)
+	}
 	// Get the logs of the block
-	logsList, err := f.backend.GetLogs(ctx, header.Hash())
+	logs, err = f.backend.GetLogsFiltered(ctx, header.Hash(), filterFn)
 	if err != nil {
 		return nil, err
 	}
-	var unfiltered []*types.Log
-	for _, logs := range logsList {
-		unfiltered = append(unfiltered, logs...)
-	}
-	logs = filterLogs(unfiltered, nil, nil, f.addresses, f.topics)
 	if len(logs) > 0 {
 		// We have matching logs, check if we need to resolve full logs via the light client
 		if logs[0].TxHash == (common.Hash{}) {
 			receipts, err := f.backend.GetReceipts(ctx, header.Hash())
 			if err != nil {
 				return nil, err
 			}
-			unfiltered = unfiltered[:0]
+			var unfiltered []*types.Log
 			for _, receipt := range receipts {
 				unfiltered = append(unfiltered, receipt.Logs...)
 			}

internal/ethapi/backend.go

@@ -84,6 +84,7 @@ type Backend interface {
 	// Filter API
 	BloomStatus() (uint64, uint64)
 	GetLogs(ctx context.Context, blockHash common.Hash) ([][]*types.Log, error)
+	GetLogsFiltered(ctx context.Context, blockHash common.Hash, _ func([]*types.Log) []*types.Log) ([]*types.Log, error)
 	ServiceFilter(ctx context.Context, session *bloombits.MatcherSession)
 	SubscribeLogsEvent(ch chan<- []*types.Log) event.Subscription
 	SubscribePendingLogsEvent(ch chan<- []*types.Log) event.Subscription

les/api_backend.go

@@ -174,6 +174,10 @@ func (b *LesApiBackend) GetLogs(ctx context.Context, hash common.Hash) ([][]*typ
 	return nil, nil
 }
 
+func (b *LesApiBackend) GetLogsFiltered(ctx context.Context, hash common.Hash, _ func([]*types.Log) []*types.Log) ([]*types.Log, error) {
+	panic("unimplemented")
+}
+
 func (b *LesApiBackend) GetTd(ctx context.Context, hash common.Hash) *big.Int {
 	if number := rawdb.ReadHeaderNumber(b.eth.chainDb, hash); number != nil {
 		return b.eth.blockchain.GetTdOdr(ctx, hash, *number)