Merge pull request #4982 from onflow/janez/change-event-emission-code

[FVM] Refactor event emission code

fvm/environment/env.go

@@ -37,7 +37,7 @@ type Environment interface {
 
 	// EventEmitter
 	Events() flow.EventsList
-	EmitFlowEvent(etype flow.EventType, payload []byte) error
+	EmitRawEvent(etype flow.EventType, payload []byte) error
 	ServiceEvents() flow.EventsList
 	ConvertedServiceEvents() flow.ServiceEventList
 

fvm/environment/event_emitter.go

@@ -38,16 +38,14 @@ func DefaultEventEmitterParams() EventEmitterParams {
 // Note that scripts do not emit events, but must expose the API in compliance
 // with the runtime environment interface.
 type EventEmitter interface {
-	// Cadence's runtime API.  Note that the script variant will return
-	// OperationNotSupportedError.
+	// EmitEvent satisfies Cadence's runtime API.
+	// This will encode the cadence event and call EmitRawEvent.
+	//
+	// Note that the script variant will return OperationNotSupportedError.
 	EmitEvent(event cadence.Event) error
 
-	// EmitFlowEvent is used to emit events that are not generated by
-	// Cadence runtime.
-	// Warning: current implementation of EmitFlowEvent does not support handling service events
-	// that functionality should be added if needed in the future
-	// TODO: we could merge this one with the EmitEvent endpoint
-	EmitFlowEvent(etype flow.EventType, payload []byte) error
+	// EmitRawEvent is used to emit events that are not Cadence events.
+	EmitRawEvent(eventType flow.EventType, payload []byte) error
 
 	Events() flow.EventsList
 	ServiceEvents() flow.EventsList
@@ -79,12 +77,12 @@ func (emitter ParseRestrictedEventEmitter) EmitEvent(event cadence.Event) error
 		event)
 }
 
-func (emitter ParseRestrictedEventEmitter) EmitFlowEvent(etype flow.EventType, payload []byte) error {
+func (emitter ParseRestrictedEventEmitter) EmitRawEvent(eventType flow.EventType, payload []byte) error {
 	return parseRestrict2Arg(
 		emitter.txnState,
 		trace.FVMEnvEmitEvent,
-		emitter.impl.EmitFlowEvent,
-		etype,
+		emitter.impl.EmitRawEvent,
+		eventType,
 		payload,
 	)
 }
@@ -111,11 +109,11 @@ var _ EventEmitter = NoEventEmitter{}
 // where emitting an event does nothing.
 type NoEventEmitter struct{}
 
-func (NoEventEmitter) EmitEvent(event cadence.Event) error {
+func (NoEventEmitter) EmitEvent(cadence.Event) error {
 	return nil
 }
 
-func (NoEventEmitter) EmitFlowEvent(etype flow.EventType, payload []byte) error {
+func (NoEventEmitter) EmitRawEvent(flow.EventType, []byte) error {
 	return nil
 }
 
@@ -180,23 +178,29 @@ func (emitter *eventEmitter) EventCollection() *EventCollection {
 }
 
 func (emitter *eventEmitter) EmitEvent(event cadence.Event) error {
-	defer emitter.tracer.StartExtensiveTracingChildSpan(
-		trace.FVMEnvEmitEvent).End()
-
-	err := emitter.meter.MeterComputation(ComputationKindEmitEvent, 1)
+	defer emitter.tracer.StartExtensiveTracingChildSpan(trace.FVMEnvEncodeEvent).End()
+	err := emitter.meter.MeterComputation(ComputationKindEncodeEvent, 1)
 	if err != nil {
-		return fmt.Errorf("emit event failed: %w", err)
+		return fmt.Errorf("emit event, event encoding failed: %w", err)
 	}
 
 	payload, err := emitter.EventEncoder.Encode(event)
 	if err != nil {
 		return errors.NewEventEncodingError(err)
 	}
 
-	payloadSize := uint64(len(payload))
+	return emitter.EmitRawEvent(flow.EventType(event.EventType.ID()), payload)
+}
 
+func (emitter *eventEmitter) EmitRawEvent(eventType flow.EventType, payload []byte) error {
+	defer emitter.tracer.StartExtensiveTracingChildSpan(trace.FVMEnvEmitEvent).End()
+	payloadSize := len(payload)
+	err := emitter.meter.MeterComputation(ComputationKindEmitEvent, uint(payloadSize))
+	if err != nil {
+		return fmt.Errorf("emit event failed: %w", err)
+	}
 	flowEvent := flow.Event{
-		Type:             flow.EventType(event.EventType.ID()),
+		Type:             eventType,
 		TransactionID:    emitter.txID,
 		TransactionIndex: emitter.txIndex,
 		EventIndex:       emitter.eventCollection.TotalEventCounter(),
@@ -207,15 +211,15 @@ func (emitter *eventEmitter) EmitEvent(event cadence.Event) error {
 	isServiceAccount := emitter.payer == emitter.chain.ServiceAddress()
 
 	if emitter.ServiceEventCollectionEnabled {
-		ok, err := IsServiceEvent(event, emitter.chain.ChainID())
+		ok, err := IsServiceEvent(eventType, emitter.chain.ChainID())
 		if err != nil {
 			return fmt.Errorf("unable to check service event: %w", err)
 		}
 		if ok {
 			eventEmitError := emitter.eventCollection.AppendServiceEvent(
 				emitter.chain,
 				flowEvent,
-				payloadSize)
+				uint64(payloadSize))
 
 			// skip limit if payer is service account
 			// TODO skip only limit-related errors
@@ -227,35 +231,14 @@ func (emitter *eventEmitter) EmitEvent(event cadence.Event) error {
 		// as well.
 	}
 
-	eventEmitError := emitter.eventCollection.AppendEvent(flowEvent, payloadSize)
+	eventEmitError := emitter.eventCollection.AppendEvent(flowEvent, uint64(payloadSize))
 	// skip limit if payer is service account
 	if !isServiceAccount {
 		return eventEmitError
 	}
 
 	return nil
-}
-
-func (emitter *eventEmitter) EmitFlowEvent(etype flow.EventType, payload []byte) error {
-	defer emitter.tracer.StartExtensiveTracingChildSpan(
-		trace.FVMEnvEmitEvent).End()
-
-	err := emitter.meter.MeterComputation(ComputationKindEmitEvent, 1)
-	if err != nil {
-		return fmt.Errorf("emit flow event failed: %w", err)
-	}
-
-	eventSize := uint64(len(etype) + len(payload))
-
-	flowEvent := flow.Event{
-		Type:             etype,
-		TransactionID:    emitter.txID,
-		TransactionIndex: emitter.txIndex,
-		EventIndex:       emitter.eventCollection.TotalEventCounter(),
-		Payload:          payload,
-	}
 
-	return emitter.eventCollection.AppendEvent(flowEvent, eventSize)
 }
 
 func (emitter *eventEmitter) Events() flow.EventsList {
@@ -334,7 +317,7 @@ func (collection *EventCollection) TotalEventCounter() uint32 {
 
 // IsServiceEvent determines whether or not an emitted Cadence event is
 // considered a service event for the given chain.
-func IsServiceEvent(event cadence.Event, chain flow.ChainID) (bool, error) {
+func IsServiceEvent(eventType flow.EventType, chain flow.ChainID) (bool, error) {
 
 	// retrieve the service event information for this chain
 	events, err := systemcontracts.ServiceEventsForChain(chain)
@@ -345,7 +328,6 @@ func IsServiceEvent(event cadence.Event, chain flow.ChainID) (bool, error) {
 			err)
 	}
 
-	eventType := flow.EventType(event.EventType.ID())
 	for _, serviceEvent := range events.All() {
 		if serviceEvent.EventType() == eventType {
 			return true, nil

fvm/environment/event_emitter_test.go

@@ -27,44 +27,50 @@ func Test_IsServiceEvent(t *testing.T) {
 
 	t.Run("correct", func(t *testing.T) {
 		for _, event := range events.All() {
-			isServiceEvent, err := environment.IsServiceEvent(cadence.Event{
+			event := cadence.Event{
 				EventType: &cadence.EventType{
 					Location: common.AddressLocation{
 						Address: common.MustBytesToAddress(
 							event.Address.Bytes()),
 					},
 					QualifiedIdentifier: event.QualifiedIdentifier(),
 				},
-			}, chain)
+			}
+
+			isServiceEvent, err := environment.IsServiceEvent(flow.EventType(event.Type().ID()), chain)
 			require.NoError(t, err)
 			assert.True(t, isServiceEvent)
 		}
 	})
 
 	t.Run("wrong chain", func(t *testing.T) {
-		isServiceEvent, err := environment.IsServiceEvent(cadence.Event{
+		event := cadence.Event{
 			EventType: &cadence.EventType{
 				Location: common.AddressLocation{
 					Address: common.MustBytesToAddress(
 						flow.Testnet.Chain().ServiceAddress().Bytes()),
 				},
 				QualifiedIdentifier: events.EpochCommit.QualifiedIdentifier(),
 			},
-		}, chain)
+		}
+
+		isServiceEvent, err := environment.IsServiceEvent(flow.EventType(event.Type().ID()), chain)
 		require.NoError(t, err)
 		assert.False(t, isServiceEvent)
 	})
 
 	t.Run("wrong type", func(t *testing.T) {
-		isServiceEvent, err := environment.IsServiceEvent(cadence.Event{
+		event := cadence.Event{
 			EventType: &cadence.EventType{
 				Location: common.AddressLocation{
 					Address: common.MustBytesToAddress(
 						chain.Chain().ServiceAddress().Bytes()),
 				},
 				QualifiedIdentifier: "SomeContract.SomeEvent",
 			},
-		}, chain)
+		}
+
+		isServiceEvent, err := environment.IsServiceEvent(flow.EventType(event.Type().ID()), chain)
 		require.NoError(t, err)
 		assert.False(t, isServiceEvent)
 	})
@@ -150,19 +156,19 @@ func Test_EmitEvent_Limit(t *testing.T) {
 		require.Error(t, err)
 	})
 
-	t.Run("emit flow event - exceeding limit", func(t *testing.T) {
+	t.Run("emit raw event - exceeding limit", func(t *testing.T) {
 		flowEvent := flow.Event{
 			Type:    "sometype",
 			Payload: []byte{1, 2, 3, 4, 5},
 		}
 
-		eventSize := uint64(len(flowEvent.Type) + len(flowEvent.Payload))
+		eventSize := uint64(len(flowEvent.Payload))
 		eventEmitter := createTestEventEmitterWithLimit(
 			flow.Emulator,
 			flow.Emulator.Chain().NewAddressGenerator().CurrentAddress(),
 			eventSize-1)
 
-		err := eventEmitter.EmitFlowEvent(flowEvent.Type, flowEvent.Payload)
+		err := eventEmitter.EmitRawEvent(flowEvent.Type, flowEvent.Payload)
 		require.Error(t, err)
 	})
 }

fvm/environment/meter.go

@@ -51,6 +51,7 @@ const (
 	ComputationKindEVMGasUsage                = 2037
 	ComputationKindRLPEncoding                = 2038
 	ComputationKindRLPDecoding                = 2039
+	ComputationKindEncodeEvent                = 2040
 )
 
 type Meter interface {

fvm/evm/handler/handler.go

@@ -139,8 +139,7 @@ func (h *ContractHandler) emitEvent(event *types.Event) {
 	// TODO add extra metering for rlp encoding
 	encoded, err := event.Payload.Encode()
 	handleError(err)
-
-	err = h.backend.EmitFlowEvent(event.Etype, encoded)
+	err = h.backend.EmitRawEvent(event.Etype, encoded)
 	handleError(err)
 }
 

fvm/evm/testutils/backend.go

@@ -77,7 +77,7 @@ func GetSimpleValueStore() *TestValueStore {
 func getSimpleEventEmitter() *testEventEmitter {
 	events := make(flow.EventsList, 0)
 	return &testEventEmitter{
-		emitFlowEvent: func(etype flow.EventType, payload []byte) error {
+		emitRawEvent: func(etype flow.EventType, payload []byte) error {
 			events = append(events, flow.Event{Type: etype, Payload: payload})
 			return nil
 		},
@@ -238,7 +238,7 @@ func (m *testMeter) TotalEmittedEventBytes() uint64 {
 
 type testEventEmitter struct {
 	emitEvent              func(event cadence.Event) error
-	emitFlowEvent          func(etype flow.EventType, payload []byte) error
+	emitRawEvent           func(etype flow.EventType, payload []byte) error
 	events                 func() flow.EventsList
 	serviceEvents          func() flow.EventsList
 	convertedServiceEvents func() flow.ServiceEventList
@@ -254,11 +254,11 @@ func (vs *testEventEmitter) EmitEvent(event cadence.Event) error {
 	return vs.emitEvent(event)
 }
 
-func (vs *testEventEmitter) EmitFlowEvent(etype flow.EventType, payload []byte) error {
-	if vs.emitFlowEvent == nil {
+func (vs *testEventEmitter) EmitRawEvent(etype flow.EventType, payload []byte) error {
+	if vs.emitRawEvent == nil {
 		panic("method not set")
 	}
-	return vs.emitFlowEvent(etype, payload)
+	return vs.emitRawEvent(etype, payload)
 }
 
 func (vs *testEventEmitter) Events() flow.EventsList {

module/trace/constants.go

@@ -167,6 +167,7 @@ const (
 	FVMEnvGetOrLoadProgram            SpanName = "fvm.env.getOrLoadCachedProgram"
 	FVMEnvProgramLog                  SpanName = "fvm.env.programLog"
 	FVMEnvEmitEvent                   SpanName = "fvm.env.emitEvent"
+	FVMEnvEncodeEvent                 SpanName = "fvm.env.encodeEvent"
 	FVMEnvGenerateUUID                SpanName = "fvm.env.generateUUID"
 	FVMEnvGenerateAccountLocalID      SpanName = "fvm.env.generateAccountLocalID"
 	FVMEnvDecodeArgument              SpanName = "fvm.env.decodeArgument"