FLIP 204: Add TargetDuration to Epoch models and API #4987

engine/execution/computation/computer/computer_test.go

@@ -1203,7 +1203,7 @@ func Test_ExecutingSystemCollection(t *testing.T) {
 	noopCollector := metrics.NewNoopCollector()
 
 	expectedNumberOfEvents := 3
-	expectedEventSize := 1457
+	expectedEventSize := 1478
 	// bootstrapping does not cache programs
 	expectedCachedPrograms := 0
 

engine/execution/state/bootstrap/bootstrap_test.go

@@ -53,7 +53,7 @@ func TestBootstrapLedger(t *testing.T) {
 }
 
 func TestBootstrapLedger_ZeroTokenSupply(t *testing.T) {
-	expectedStateCommitmentBytes, _ := hex.DecodeString("356275de4a0abb9674872397fe7d91aa1430ea0dcd9c5cc18bffc5e61a54cbc0")
+	expectedStateCommitmentBytes, _ := hex.DecodeString("03077009b61e3c7d185df77d21bf752cf4b48c69045f98e7e8f964cef135546b")
 	expectedStateCommitment, err := flow.ToStateCommitment(expectedStateCommitmentBytes)
 	require.NoError(t, err)
 

go.mod

@@ -53,7 +53,7 @@ require (
 	github.com/onflow/atree v0.6.0
 	github.com/onflow/cadence v0.42.4
 	github.com/onflow/flow v0.3.4
-	github.com/onflow/flow-core-contracts/lib/go/contracts v1.2.4-0.20231111185227-240579784e9b
+	github.com/onflow/flow-core-contracts/lib/go/contracts v1.2.4-0.20231120143830-9e8417b56122
 	github.com/onflow/flow-core-contracts/lib/go/templates v1.2.4-0.20231111185227-240579784e9b
 	github.com/onflow/flow-go-sdk v0.41.14
 	github.com/onflow/flow-go/crypto v0.24.9

go.sum

@@ -1329,8 +1329,8 @@ github.com/onflow/cadence v0.42.4 h1:KoXnwPCMcjixZv+gHZwWkDiAyVExJhJJe6SebdnHNv8
 github.com/onflow/cadence v0.42.4/go.mod h1:raU8va8QRyTa/eUbhej4mbyW2ETePfSaywoo36MddgE=
 github.com/onflow/flow v0.3.4 h1:FXUWVdYB90f/rjNcY0Owo30gL790tiYff9Pb/sycXYE=
 github.com/onflow/flow v0.3.4/go.mod h1:lzyAYmbu1HfkZ9cfnL5/sjrrsnJiUU8fRL26CqLP7+c=
-github.com/onflow/flow-core-contracts/lib/go/contracts v1.2.4-0.20231111185227-240579784e9b h1:TTN9nlagR6z0dlUGDGF6WK7jhIe5vB0Xayj3pyBk7mA=
-github.com/onflow/flow-core-contracts/lib/go/contracts v1.2.4-0.20231111185227-240579784e9b/go.mod h1:jM6GMAL+m0hjusUgiYDNrixPQ6b9s8xjoJQoEu5bHQI=
+github.com/onflow/flow-core-contracts/lib/go/contracts v1.2.4-0.20231120143830-9e8417b56122 h1:yUzR59WUue8BN/bfwy0eN4YOLYXeQ3G9I53H0amxbDU=
+github.com/onflow/flow-core-contracts/lib/go/contracts v1.2.4-0.20231120143830-9e8417b56122/go.mod h1:jM6GMAL+m0hjusUgiYDNrixPQ6b9s8xjoJQoEu5bHQI=
 github.com/onflow/flow-core-contracts/lib/go/templates v1.2.4-0.20231111185227-240579784e9b h1:Q9iCekuCTeZU3CkVRTj5BhMBY/vR/uA2K63JTl5vCD8=
 github.com/onflow/flow-core-contracts/lib/go/templates v1.2.4-0.20231111185227-240579784e9b/go.mod h1:ZeLxwaBkzuSInESGjL8/IPZWezF+YOYsYbMrZlhN+q4=
 github.com/onflow/flow-ft/lib/go/contracts v0.7.1-0.20230711213910-baad011d2b13 h1:B4ll7e3j+MqTJv2122Enq3RtDNzmIGRu9xjV7fo7un0=

insecure/go.mod

@@ -191,7 +191,7 @@ require (
 	github.com/multiformats/go-varint v0.0.7 // indirect
 	github.com/onflow/atree v0.6.0 // indirect
 	github.com/onflow/cadence v0.42.4 // indirect
-	github.com/onflow/flow-core-contracts/lib/go/contracts v1.2.4-0.20231111185227-240579784e9b // indirect
+	github.com/onflow/flow-core-contracts/lib/go/contracts v1.2.4-0.20231120143830-9e8417b56122 // indirect
 	github.com/onflow/flow-core-contracts/lib/go/templates v1.2.4-0.20231111185227-240579784e9b // indirect
 	github.com/onflow/flow-ft/lib/go/contracts v0.7.1-0.20230711213910-baad011d2b13 // indirect
 	github.com/onflow/flow-go-sdk v0.41.14 // indirect

insecure/go.sum

@@ -1284,8 +1284,8 @@ github.com/onflow/atree v0.6.0/go.mod h1:gBHU0M05qCbv9NN0kijLWMgC47gHVNBIp4KmsVF
 github.com/onflow/cadence v0.20.1/go.mod h1:7mzUvPZUIJztIbr9eTvs+fQjWWHTF8veC+yk4ihcNIA=
 github.com/onflow/cadence v0.42.4 h1:KoXnwPCMcjixZv+gHZwWkDiAyVExJhJJe6SebdnHNv8=
 github.com/onflow/cadence v0.42.4/go.mod h1:raU8va8QRyTa/eUbhej4mbyW2ETePfSaywoo36MddgE=
-github.com/onflow/flow-core-contracts/lib/go/contracts v1.2.4-0.20231111185227-240579784e9b h1:TTN9nlagR6z0dlUGDGF6WK7jhIe5vB0Xayj3pyBk7mA=
-github.com/onflow/flow-core-contracts/lib/go/contracts v1.2.4-0.20231111185227-240579784e9b/go.mod h1:jM6GMAL+m0hjusUgiYDNrixPQ6b9s8xjoJQoEu5bHQI=
+github.com/onflow/flow-core-contracts/lib/go/contracts v1.2.4-0.20231120143830-9e8417b56122 h1:yUzR59WUue8BN/bfwy0eN4YOLYXeQ3G9I53H0amxbDU=
+github.com/onflow/flow-core-contracts/lib/go/contracts v1.2.4-0.20231120143830-9e8417b56122/go.mod h1:jM6GMAL+m0hjusUgiYDNrixPQ6b9s8xjoJQoEu5bHQI=
 github.com/onflow/flow-core-contracts/lib/go/templates v1.2.4-0.20231111185227-240579784e9b h1:Q9iCekuCTeZU3CkVRTj5BhMBY/vR/uA2K63JTl5vCD8=
 github.com/onflow/flow-core-contracts/lib/go/templates v1.2.4-0.20231111185227-240579784e9b/go.mod h1:ZeLxwaBkzuSInESGjL8/IPZWezF+YOYsYbMrZlhN+q4=
 github.com/onflow/flow-ft/lib/go/contracts v0.7.1-0.20230711213910-baad011d2b13 h1:B4ll7e3j+MqTJv2122Enq3RtDNzmIGRu9xjV7fo7un0=

integration/go.mod

@@ -19,7 +19,7 @@ require (
 	github.com/ipfs/go-ds-badger2 v0.1.3
 	github.com/ipfs/go-ipfs-blockstore v1.3.0
 	github.com/onflow/cadence v0.42.4
-	github.com/onflow/flow-core-contracts/lib/go/contracts v1.2.4-0.20231111185227-240579784e9b
+	github.com/onflow/flow-core-contracts/lib/go/contracts v1.2.4-0.20231120143830-9e8417b56122
 	github.com/onflow/flow-core-contracts/lib/go/templates v1.2.4-0.20231111185227-240579784e9b
 	github.com/onflow/flow-emulator v0.54.1-0.20231024204057-0273f8fe3807
 	github.com/onflow/flow-go v0.32.3

integration/go.sum

@@ -1376,8 +1376,8 @@ github.com/onflow/atree v0.6.0/go.mod h1:gBHU0M05qCbv9NN0kijLWMgC47gHVNBIp4KmsVF
 github.com/onflow/cadence v0.20.1/go.mod h1:7mzUvPZUIJztIbr9eTvs+fQjWWHTF8veC+yk4ihcNIA=
 github.com/onflow/cadence v0.42.4 h1:KoXnwPCMcjixZv+gHZwWkDiAyVExJhJJe6SebdnHNv8=
 github.com/onflow/cadence v0.42.4/go.mod h1:raU8va8QRyTa/eUbhej4mbyW2ETePfSaywoo36MddgE=
-github.com/onflow/flow-core-contracts/lib/go/contracts v1.2.4-0.20231111185227-240579784e9b h1:TTN9nlagR6z0dlUGDGF6WK7jhIe5vB0Xayj3pyBk7mA=
-github.com/onflow/flow-core-contracts/lib/go/contracts v1.2.4-0.20231111185227-240579784e9b/go.mod h1:jM6GMAL+m0hjusUgiYDNrixPQ6b9s8xjoJQoEu5bHQI=
+github.com/onflow/flow-core-contracts/lib/go/contracts v1.2.4-0.20231120143830-9e8417b56122 h1:yUzR59WUue8BN/bfwy0eN4YOLYXeQ3G9I53H0amxbDU=
+github.com/onflow/flow-core-contracts/lib/go/contracts v1.2.4-0.20231120143830-9e8417b56122/go.mod h1:jM6GMAL+m0hjusUgiYDNrixPQ6b9s8xjoJQoEu5bHQI=
 github.com/onflow/flow-core-contracts/lib/go/templates v1.2.4-0.20231111185227-240579784e9b h1:Q9iCekuCTeZU3CkVRTj5BhMBY/vR/uA2K63JTl5vCD8=
 github.com/onflow/flow-core-contracts/lib/go/templates v1.2.4-0.20231111185227-240579784e9b/go.mod h1:ZeLxwaBkzuSInESGjL8/IPZWezF+YOYsYbMrZlhN+q4=
 github.com/onflow/flow-emulator v0.54.1-0.20231024204057-0273f8fe3807 h1:/4jZ2oELdhKubgL97NGqhiuO80oMH/M+fIQoNPfGg+g=

model/convert/service_event.go

@@ -54,7 +54,7 @@ func convertServiceEventEpochSetup(event flow.Event) (*flow.ServiceEvent, error)
 		return nil, invalidCadenceTypeError("payload", payload, cadence.Event{})
 	}
 
-	const expectedFieldCount = 10
+	const expectedFieldCount = 11
 	if len(cdcEvent.Fields) < expectedFieldCount {
 		return nil, fmt.Errorf(
 			"insufficient fields in EpochSetup event (%d < %d)",
@@ -78,6 +78,7 @@ func convertServiceEventEpochSetup(event flow.Event) (*flow.ServiceEvent, error)
 	var dkgPhase3FinalView cadence.UInt64
 	var cdcClusters cadence.Array
 	var cdcParticipants cadence.Array
+	var targetDuration cadence.UInt64    // Epoch duration [seconds]
 	var targetEndTimeUnix cadence.UInt64 // Unix time [seconds]
 
 	var foundFieldCount int
@@ -152,6 +153,17 @@ func convertServiceEventEpochSetup(event flow.Event) (*flow.ServiceEvent, error)
 				)
 			}
 
+		case "targetDuration":
+			foundFieldCount++
+			targetDuration, ok = cdcEvent.Fields[i].(cadence.UInt64)
+			if !ok {
+				return nil, invalidCadenceTypeError(
+					"targetDuration",
+					cdcEvent.Fields[i],
+					cadence.UInt64(0),
+				)
+			}
+
 		case "targetEndTime":
 			foundFieldCount++
 			targetEndTimeUnix, ok = cdcEvent.Fields[i].(cadence.UInt64)
@@ -213,6 +225,7 @@ func convertServiceEventEpochSetup(event flow.Event) (*flow.ServiceEvent, error)
 		DKGPhase1FinalView: uint64(dkgPhase1FinalView),
 		DKGPhase2FinalView: uint64(dkgPhase2FinalView),
 		DKGPhase3FinalView: uint64(dkgPhase3FinalView),
+		TargetDuration:     uint64(targetDuration),
 		TargetEndTime:      uint64(targetEndTimeUnix),
 	}
 

model/flow/epoch.go

@@ -72,6 +72,7 @@ type EpochSetup struct {
 	Participants       IdentityList   // all participants of the epoch
 	Assignments        AssignmentList // cluster assignment for the epoch
 	RandomSource       []byte         // source of randomness for epoch-specific setup tasks
+	TargetDuration     uint64         // desired real-world duration for the epoch [seconds]
 	TargetEndTime      uint64         // desired real-world end time for the epoch in UNIX time [seconds]
 }
 

state/protocol/epoch.go

@@ -97,6 +97,15 @@ type Epoch interface {
 	// * state.ErrUnknownSnapshotReference - if the epoch is queried from an unresolvable snapshot.
 	FinalView() (uint64, error)
 
+	// TargetDuration returns the desired real-world duration for this epoch, in seconds.
+	// This target is specified by the FlowEpoch smart contract along the TargetEndTime in
+	// the EpochSetup event and used by the Cruise Control system to moderate the block rate.
+	// Error returns:
+	// * protocol.ErrNoPreviousEpoch - if the epoch represents a previous epoch which does not exist.
+	// * protocol.ErrNextEpochNotSetup - if the epoch represents a next epoch which has not been set up.
+	// * state.ErrUnknownSnapshotReference - if the epoch is queried from an unresolvable snapshot.
+	TargetDuration() (uint64, error)
+
 	// TargetEndTime returns the desired real-world end time for this epoch, represented as
 	// Unix Time (in units of seconds). This target is specified by the FlowEpoch smart contract in
 	// the EpochSetup event and used by the Cruise Control system to moderate the block rate.

state/protocol/inmem/convert.go

@@ -157,6 +157,10 @@ func FromEpoch(from protocol.Epoch) (*Epoch, error) {
 	if err != nil {
 		return nil, fmt.Errorf("could not get random source: %w", err)
 	}
+	epoch.TargetDuration, err = from.TargetDuration()
+	if err != nil {
+		return nil, fmt.Errorf("could not get target epoch duration: %w", err)
+	}
 	epoch.TargetEndTime, err = from.TargetEndTime()
 	if err != nil {
 		return nil, fmt.Errorf("could not get target end time: %w", err)

state/protocol/inmem/encodable.go

@@ -36,6 +36,7 @@ type EncodableEpoch struct {
 	DKGPhase3FinalView uint64
 	FinalView          uint64
 	RandomSource       []byte
+	TargetDuration     uint64 // desired real-world end time for the epoch in seconds
 	TargetEndTime      uint64 // desired real-world end time for the epoch in unix time [seconds]
 	InitialIdentities  flow.IdentityList
 	Clustering         flow.ClusterList

state/protocol/inmem/epoch.go

@@ -37,6 +37,13 @@ func (e Epoch) RandomSource() ([]byte, error) {
 	return e.enc.RandomSource, nil
 }
 
+// TargetDuration returns the desired real-world duration for this epoch, in seconds.
+// This target is specified by the FlowEpoch smart contract in the EpochSetup event
+// and used by the Cruise Control system to moderate the block rate.
+func (e Epoch) TargetDuration() (uint64, error) {
+	return e.enc.TargetDuration, nil
+}
+
 // TargetEndTime returns the desired real-world end time for this epoch, represented as
 // Unix Time (in units of seconds). This target is specified by the FlowEpoch smart contract in
 // the EpochSetup event and used by the Cruise Control system to moderate the block rate.
@@ -150,6 +157,13 @@ func (es *setupEpoch) FinalView() (uint64, error) {
 	return es.setupEvent.FinalView, nil
 }
 
+// TargetDuration returns the desired real-world duration for this epoch, in seconds.
+// This target is specified by the FlowEpoch smart contract in the EpochSetup event
+// and used by the Cruise Control system to moderate the block rate.
+func (es *setupEpoch) TargetDuration() (uint64, error) {
+	return es.setupEvent.TargetDuration, nil
+}
+
 // TargetEndTime returns the desired real-world end time for this epoch, represented as
 // Unix Time (in units of seconds). This target is specified by the FlowEpoch smart contract in
 // the EpochSetup event and used by the Cruise Control system to moderate the block rate.

state/protocol/invalid/epoch.go

@@ -89,6 +89,10 @@ func (u *Epoch) RandomSource() ([]byte, error) {
 	return nil, u.err
 }
 
+func (u *Epoch) TargetDuration() (uint64, error) {
+	return 0, u.err
+}
+
 func (u *Epoch) TargetEndTime() (uint64, error) {
 	return 0, u.err
 }

utils/unittest/execution_state.go

@@ -24,7 +24,7 @@ const ServiceAccountPrivateKeySignAlgo = crypto.ECDSAP256
 const ServiceAccountPrivateKeyHashAlgo = hash.SHA2_256
 
 // Pre-calculated state commitment with root account with the above private key
-const GenesisStateCommitmentHex = "b9a64ba52bcbc795c162d69655d645fac70dda9395587590e06bab98669dc9df"
+const GenesisStateCommitmentHex = "3b3197e640e7bc171e73cfeb0c26b779fda0c28af383fefff60b3d47e8a4d38e"
 
 var GenesisStateCommitment flow.StateCommitment
 
@@ -88,10 +88,10 @@ func genesisCommitHexByChainID(chainID flow.ChainID) string {
 		return GenesisStateCommitmentHex
 	}
 	if chainID == flow.Testnet {
-		return "498844490ee8718b5c0362f4405c61356c771845718efc2841530772f8f425be"
+		return "7192a942310f70b21579f3e3bbf6f381a2c350e23130b465aa6a25f4c7612d87"
 	}
 	if chainID == flow.Sandboxnet {
 		return "e1c08b17f9e5896f03fe28dd37ca396c19b26628161506924fbf785834646ea1"
 	}
-	return "80d6a73ca02abd8900fa325edbb5014d91475409ae39fe0eb7925ef85d1647e3"
+	return "93fc7a1d086c25794822a034288f33580bd1eca485ffab1a36691590518606fa"
 }

utils/unittest/service_events_fixtures.go

@@ -37,6 +37,7 @@ func EpochSetupFixtureByChainID(chain flow.ChainID) (flow.Event, *flow.EpochSetu
 		DKGPhase2FinalView: 160,
 		DKGPhase3FinalView: 170,
 		RandomSource:       randomSource,
+		TargetDuration:     200,
 		TargetEndTime:      2000000000,
 		Assignments: flow.AssignmentList{
 			{
@@ -205,6 +206,9 @@ func createEpochSetupEvent() cadence.Event {
 		// DKGPhase3FinalView
 		cadence.UInt64(170),
 
+		// targetDuration
+		cadence.UInt64(200),
+
 		// targetEndTime
 		cadence.UInt64(2000000000),
 	}).WithType(newFlowEpochEpochSetupEventType())
@@ -885,6 +889,10 @@ func newFlowEpochEpochSetupEventType() *cadence.EventType {
 				Identifier: "DKGPhase3FinalView",
 				Type:       cadence.UInt64Type{},
 			},
+			{
+				Identifier: "targetDuration",
+				Type:       cadence.UInt64Type{},
+			},
 			{
 				Identifier: "targetEndTime",
 				Type:       cadence.UInt64Type{},