github.com/pokt-network/tendermint@v0.32.11-0.20230426215212-59310158d3e9/state/txindex/indexer_service.go (about)

     1  package txindex
     2  
     3  import (
     4  	"context"
     5  	"github.com/tendermint/tendermint/libs/log"
     6  
     7  	"github.com/tendermint/tendermint/libs/service"
     8  
     9  	"github.com/tendermint/tendermint/types"
    10  )
    11  
    12  const (
    13  	subscriber = "IndexerService"
    14  )
    15  
    16  // IndexerService connects event bus and transaction indexer together in order
    17  // to index transactions coming from event bus.
    18  type IndexerService struct {
    19  	service.BaseService
    20  
    21  	idr      TxIndexer
    22  	eventBus *types.EventBus
    23  }
    24  
    25  // NewIndexerService returns a new service instance.
    26  func NewIndexerService(idr TxIndexer, eventBus *types.EventBus) *IndexerService {
    27  	is := &IndexerService{idr: idr, eventBus: eventBus}
    28  	is.BaseService = *service.NewBaseService(nil, "IndexerService", is)
    29  	return is
    30  }
    31  
    32  // OnStart implements service.Service by subscribing for all transactions
    33  // and indexing them by events.
    34  func (is *IndexerService) OnStart() error {
    35  	// Use SubscribeUnbuffered here to ensure both subscriptions does not get
    36  	// cancelled due to not pulling messages fast enough. Cause this might
    37  	// sometimes happen when there are no other subscribers.
    38  
    39  	blockHeadersSub, err := is.eventBus.SubscribeUnbuffered(
    40  		context.Background(),
    41  		subscriber,
    42  		types.EventQueryNewBlockHeader)
    43  	if err != nil {
    44  		return err
    45  	}
    46  
    47  	txsSub, err := is.eventBus.SubscribeUnbuffered(context.Background(), subscriber, types.EventQueryTx)
    48  	if err != nil {
    49  		return err
    50  	}
    51  
    52  	go func() {
    53  		for {
    54  			msg := <-blockHeadersSub.Out()
    55  			eventDataHeader := msg.Data().(types.EventDataNewBlockHeader).Header
    56  			height := eventDataHeader.Height
    57  			batch := NewBatch(eventDataHeader.NumTxs)
    58  			for i := int64(0); i < eventDataHeader.NumTxs; i++ {
    59  				msg2 := <-txsSub.Out()
    60  				txResult := msg2.Data().(types.EventDataTx).TxResult
    61  				if err = batch.Add(&txResult); err != nil {
    62  					is.Logger.Error("Can't add tx to batch",
    63  						"height", height,
    64  						"index", txResult.Index,
    65  						"err", err)
    66  				}
    67  			}
    68  			if err = is.idr.AddBatch(batch); err != nil {
    69  				is.Logger.Error("Failed to index block", "height", height, "err", err)
    70  			} else {
    71  				is.Logger.Info("Indexed block", "height", height)
    72  			}
    73  		}
    74  	}()
    75  	return nil
    76  }
    77  
    78  // OnStop implements service.Service by unsubscribing from all transactions.
    79  func (is *IndexerService) OnStop() {
    80  	if is.eventBus.IsRunning() {
    81  		_ = is.eventBus.UnsubscribeAll(context.Background(), subscriber)
    82  	}
    83  }
    84  
    85  func SyncTxIndexer(logger log.Logger, idr TxIndexer, b *Batch, height int64) {
    86  	if idr != nil {
    87  		if err := idr.AddBatch(b); err != nil {
    88  			logger.Error("Failed to index block", "height", height, "err", err)
    89  		} else {
    90  			logger.Info("Indexed block", "height", height)
    91  		}
    92  	}
    93  }