eth, les, light: filter on logs only, derive receipts on demand

eth/filters/filter.go

@@ -34,6 +34,7 @@ type Backend interface {
 	EventMux() *event.TypeMux
 	HeaderByNumber(ctx context.Context, blockNr rpc.BlockNumber) (*types.Header, error)
 	GetReceipts(ctx context.Context, blockHash common.Hash) (types.Receipts, error)
+	GetLogs(ctx context.Context, blockHash common.Hash) ([][]*types.Log, error)
 
 	SubscribeTxPreEvent(chan<- core.TxPreEvent) event.Subscription
 	SubscribeChainEvent(ch chan<- core.ChainEvent) event.Subscription
@@ -201,16 +202,28 @@ func (f *Filter) unindexedLogs(ctx context.Context, end uint64) ([]*types.Log, e
 // 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) {
 	// Get the logs of the block
-	receipts, err := f.backend.GetReceipts(ctx, header.Hash())
+	logsList, err := f.backend.GetLogs(ctx, header.Hash())
 	if err != nil {
 		return nil, err
 	}
 	var unfiltered []*types.Log
-	for _, receipt := range receipts {
-		unfiltered = append(unfiltered, receipt.Logs...)
+	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]
+			for _, receipt := range receipts {
+				unfiltered = append(unfiltered, receipt.Logs...)
+			}
+			logs = filterLogs(unfiltered, nil, nil, f.addresses, f.topics)
+		}
 		return logs, nil
 	}
 	return nil, nil

eth/filters/filter_system.go

@@ -375,19 +375,35 @@ func (es *EventSystem) lightFilterLogs(header *types.Header, addresses []common.
 		// Get the logs of the block
 		ctx, cancel := context.WithTimeout(context.Background(), time.Second*5)
 		defer cancel()
-		receipts, err := es.backend.GetReceipts(ctx, header.Hash())
+		logsList, err := es.backend.GetLogs(ctx, header.Hash())
 		if err != nil {
 			return nil
 		}
 		var unfiltered []*types.Log
-		for _, receipt := range receipts {
-			for _, log := range receipt.Logs {
+		for _, logs := range logsList {
+			for _, log := range logs {
 				logcopy := *log
 				logcopy.Removed = remove
 				unfiltered = append(unfiltered, &logcopy)
 			}
 		}
 		logs := filterLogs(unfiltered, nil, nil, addresses, topics)
+		if len(logs) > 0 && logs[0].TxHash == (common.Hash{}) {
+			// We have matching but non-derived logs
+			receipts, err := es.backend.GetReceipts(ctx, header.Hash())
+			if err != nil {
+				return nil
+			}
+			unfiltered = unfiltered[:0]
+			for _, receipt := range receipts {
+				for _, log := range receipt.Logs {
+					logcopy := *log
+					logcopy.Removed = remove
+					unfiltered = append(unfiltered, &logcopy)
+				}
+			}
+			logs = filterLogs(unfiltered, nil, nil, addresses, topics)
+		}
 		return logs
 	}
 	return nil

eth/filters/filter_system_test.go

@@ -69,8 +69,19 @@ func (b *testBackend) HeaderByNumber(ctx context.Context, blockNr rpc.BlockNumbe
 }
 
 func (b *testBackend) GetReceipts(ctx context.Context, blockHash common.Hash) (types.Receipts, error) {
-	num := core.GetBlockNumber(b.db, blockHash)
-	return core.GetBlockReceipts(b.db, blockHash, num), nil
+	number := core.GetBlockNumber(b.db, blockHash)
+	return core.GetBlockReceipts(b.db, blockHash, number), nil
+}
+
+func (b *testBackend) GetLogs(ctx context.Context, blockHash common.Hash) ([][]*types.Log, error) {
+	number := core.GetBlockNumber(b.db, blockHash)
+	receipts := core.GetBlockReceipts(b.db, blockHash, number)
+
+	logs := make([][]*types.Log, len(receipts))
+	for i, receipt := range receipts {
+		logs[i] = receipt.Logs
+	}
+	return logs, nil
 }
 
 func (b *testBackend) SubscribeTxPreEvent(ch chan<- core.TxPreEvent) event.Subscription {