Merge pull request #737 from onflow/petera/making-poc-configurable

Make PoC configurable

bootstrap/bootstrap.go

@@ -142,13 +142,24 @@ func (b *Bootstrap) StartEventIngestion(ctx context.Context) error {
 	chainID := b.config.FlowNetworkID
 
 	// create event subscriber
-	subscriber := ingestion.NewRPCBlockTrackingSubscriber(
-		b.logger,
-		b.client,
-		chainID,
-		b.keystore,
-		latestCadenceHeight,
-	)
+	var subscriber ingestion.EventSubscriber
+	if b.config.ExperimentalSoftFinalityEnabled {
+		subscriber = ingestion.NewRPCBlockTrackingSubscriber(
+			b.logger,
+			b.client,
+			chainID,
+			b.keystore,
+			latestCadenceHeight,
+		)
+	} else {
+		subscriber = ingestion.NewRPCEventSubscriber(
+			b.logger,
+			b.client,
+			chainID,
+			b.keystore,
+			latestCadenceHeight,
+		)
+	}
 
 	callTracerCollector, err := replayer.NewCallTracerCollector(b.logger)
 	if err != nil {

cmd/run/cmd.go

@@ -222,6 +222,8 @@ func parseConfigFromFlags() error {
 		return fmt.Errorf("unknown tx state validation: %s", txStateValidation)
 	}
 
+	cfg.ExperimentalSoftFinalityEnabled = experimentalSoftFinalityEnabled
+
 	return nil
 }
 
@@ -246,6 +248,8 @@ var (
 
 	initHeight,
 	forceStartHeight uint64
+
+	experimentalSoftFinalityEnabled bool
 )
 
 func init() {
@@ -280,4 +284,5 @@ func init() {
 	Cmd.Flags().StringVar(&cfg.ProfilerHost, "profiler-host", "localhost", "Host for the Profiler server")
 	Cmd.Flags().IntVar(&cfg.ProfilerPort, "profiler-port", 6060, "Port for the Profiler server")
 	Cmd.Flags().StringVar(&txStateValidation, "tx-state-validation", "tx-seal", "Sets the transaction validation mechanism. It can validate using the local state index, or wait for the outer Flow transaction to seal. Available values ('local-index' / 'tx-seal'), defaults to 'tx-seal'.")
+	Cmd.Flags().BoolVar(&experimentalSoftFinalityEnabled, "experimental-soft-finality-enabled", false, "Sets whether the gateway should use the experimental soft finality feature. WARNING: This may result in incorrect results being returned in certain circumstances. Use only if you know what you are doing.")
 }

config/config.go

@@ -89,4 +89,8 @@ type Config struct {
 	// TxStateValidation sets the transaction validation mechanism. It can validate
 	// using the local state index, or wait for the outer Flow transaction to seal.
 	TxStateValidation string
+	// ExperimentalSoftFinalityEnabled enables the experimental soft finality feature which syncs
+	// EVM block and transaction data from the upstream Access node before the block is sealed.
+	// CAUTION: This feature is experimental and may return incorrect data in certain circumstances.
+	ExperimentalSoftFinalityEnabled bool
 }