Epoch setup random source update

engine/execution/computation/computer/computer_test.go

@@ -602,7 +602,8 @@ func TestBlockExecutor_ExecuteBlock(t *testing.T) {
 			serviceEvents, err := systemcontracts.ServiceEventsForChain(execCtx.Chain.ChainID())
 			require.NoError(t, err)
 
-			payload, err := ccf.Decode(nil, unittest.EpochSetupFixtureCCF)
+			randomSource := unittest.EpochSetupRandomSourceFixture()
+			payload, err := ccf.Decode(nil, unittest.EpochSetupFixtureCCF(randomSource))
 			require.NoError(t, err)
 
 			serviceEventA, ok := payload.(cadence.Event)
@@ -1256,7 +1257,7 @@ func Test_ExecutingSystemCollection(t *testing.T) {
 	noopCollector := metrics.NewNoopCollector()
 
 	expectedNumberOfEvents := 3
-	expectedEventSize := 1434
+	expectedEventSize := 1493
 	// 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("33ff069b59f8eab1e58a15875bf859ebfc2068432c5cd7680ca084dbfc6c60ed")
+	expectedStateCommitmentBytes, _ := hex.DecodeString("7dc2d3ec95c5f7376512f558e4349b60d535b4f48371f9846dcf7076dd589889")
 	expectedStateCommitment, err := flow.ToStateCommitment(expectedStateCommitmentBytes)
 	require.NoError(t, err)
 

go.mod

@@ -53,8 +53,8 @@ require (
 	github.com/onflow/atree v0.6.0
 	github.com/onflow/cadence v0.42.5
 	github.com/onflow/flow v0.3.4
-	github.com/onflow/flow-core-contracts/lib/go/contracts v0.14.0
-	github.com/onflow/flow-core-contracts/lib/go/templates v0.14.0
+	github.com/onflow/flow-core-contracts/lib/go/contracts v0.15.1-0.20231130031602-3a326a55abcf
+	github.com/onflow/flow-core-contracts/lib/go/templates v0.15.1-0.20231130031602-3a326a55abcf
 	github.com/onflow/flow-go-sdk v0.41.16
 	github.com/onflow/flow-go/crypto v0.24.9
 	github.com/onflow/flow/protobuf/go/flow v0.3.2-0.20231121210617-52ee94b830c2

go.sum

@@ -1329,10 +1329,10 @@ github.com/onflow/cadence v0.42.5 h1:QCilotmJzfRToLd+02o3N62JIioSr8FfN7cujmR/IXQ
 github.com/onflow/cadence v0.42.5/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 v0.14.0 h1:DpkgyNAP3SAe7dMQX/Tb7BWFstodqtREo4hxWFHwdS0=
-github.com/onflow/flow-core-contracts/lib/go/contracts v0.14.0/go.mod h1:jM6GMAL+m0hjusUgiYDNrixPQ6b9s8xjoJQoEu5bHQI=
-github.com/onflow/flow-core-contracts/lib/go/templates v0.14.0 h1:qZoMYSe7LaO2s6DWyB781FDntyded/gX5Guihldiv54=
-github.com/onflow/flow-core-contracts/lib/go/templates v0.14.0/go.mod h1:ZeLxwaBkzuSInESGjL8/IPZWezF+YOYsYbMrZlhN+q4=
+github.com/onflow/flow-core-contracts/lib/go/contracts v0.15.1-0.20231130031602-3a326a55abcf h1:pTtEnxbfsnPwYsPpAgwZdg5QlvynkfMdFEFpdaafz1I=
+github.com/onflow/flow-core-contracts/lib/go/contracts v0.15.1-0.20231130031602-3a326a55abcf/go.mod h1:jM6GMAL+m0hjusUgiYDNrixPQ6b9s8xjoJQoEu5bHQI=
+github.com/onflow/flow-core-contracts/lib/go/templates v0.15.1-0.20231130031602-3a326a55abcf h1:9N4rwnWbJ392bcqa4MmQszsvLpl+gFrOoDfPdkZB5EA=
+github.com/onflow/flow-core-contracts/lib/go/templates v0.15.1-0.20231130031602-3a326a55abcf/go.mod h1:ZeLxwaBkzuSInESGjL8/IPZWezF+YOYsYbMrZlhN+q4=
 github.com/onflow/flow-ft/lib/go/contracts v0.7.1-0.20230711213910-baad011d2b13 h1:B4ll7e3j+MqTJv2122Enq3RtDNzmIGRu9xjV7fo7un0=
 github.com/onflow/flow-ft/lib/go/contracts v0.7.1-0.20230711213910-baad011d2b13/go.mod h1:kTMFIySzEJJeupk+7EmXs0EJ6CBWY/MV9fv9iYQk+RU=
 github.com/onflow/flow-go-sdk v0.24.0/go.mod h1:IoptMLPyFXWvyd9yYA6/4EmSeeozl6nJoIv4FaEMg74=

insecure/go.mod

@@ -199,8 +199,8 @@ require (
 	github.com/olekukonko/tablewriter v0.0.5 // indirect
 	github.com/onflow/atree v0.6.0 // indirect
 	github.com/onflow/cadence v0.42.5 // indirect
-	github.com/onflow/flow-core-contracts/lib/go/contracts v1.2.4-0.20231016154253-a00dbf7c061f // indirect
-	github.com/onflow/flow-core-contracts/lib/go/templates v1.2.4-0.20231016154253-a00dbf7c061f // indirect
+	github.com/onflow/flow-core-contracts/lib/go/contracts v0.15.1-0.20231130031602-3a326a55abcf // indirect
+	github.com/onflow/flow-core-contracts/lib/go/templates v0.15.1-0.20231130031602-3a326a55abcf // indirect
 	github.com/onflow/flow-ft/lib/go/contracts v0.7.1-0.20230711213910-baad011d2b13 // indirect
 	github.com/onflow/flow-go-sdk v0.41.16 // indirect
 	github.com/onflow/flow-nft/lib/go/contracts v1.1.0 // indirect

insecure/go.sum

@@ -1303,10 +1303,10 @@ 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 v0.42.5 h1:QCilotmJzfRToLd+02o3N62JIioSr8FfN7cujmR/IXQ=
 github.com/onflow/cadence v0.42.5/go.mod h1:raU8va8QRyTa/eUbhej4mbyW2ETePfSaywoo36MddgE=
-github.com/onflow/flow-core-contracts/lib/go/contracts v1.2.4-0.20231016154253-a00dbf7c061f h1:S8yIZw9LFXfYD1V5H9BiixihHw3GrXVPrmfplSzYaww=
-github.com/onflow/flow-core-contracts/lib/go/contracts v1.2.4-0.20231016154253-a00dbf7c061f/go.mod h1:jM6GMAL+m0hjusUgiYDNrixPQ6b9s8xjoJQoEu5bHQI=
-github.com/onflow/flow-core-contracts/lib/go/templates v1.2.4-0.20231016154253-a00dbf7c061f h1:Ep+Mpo2miWMe4pjPGIaEvEzshRep30dvNgxqk+//FrQ=
-github.com/onflow/flow-core-contracts/lib/go/templates v1.2.4-0.20231016154253-a00dbf7c061f/go.mod h1:ZeLxwaBkzuSInESGjL8/IPZWezF+YOYsYbMrZlhN+q4=
+github.com/onflow/flow-core-contracts/lib/go/contracts v0.15.1-0.20231130031602-3a326a55abcf h1:pTtEnxbfsnPwYsPpAgwZdg5QlvynkfMdFEFpdaafz1I=
+github.com/onflow/flow-core-contracts/lib/go/contracts v0.15.1-0.20231130031602-3a326a55abcf/go.mod h1:jM6GMAL+m0hjusUgiYDNrixPQ6b9s8xjoJQoEu5bHQI=
+github.com/onflow/flow-core-contracts/lib/go/templates v0.15.1-0.20231130031602-3a326a55abcf h1:9N4rwnWbJ392bcqa4MmQszsvLpl+gFrOoDfPdkZB5EA=
+github.com/onflow/flow-core-contracts/lib/go/templates v0.15.1-0.20231130031602-3a326a55abcf/go.mod h1:ZeLxwaBkzuSInESGjL8/IPZWezF+YOYsYbMrZlhN+q4=
 github.com/onflow/flow-ft/lib/go/contracts v0.7.1-0.20230711213910-baad011d2b13 h1:B4ll7e3j+MqTJv2122Enq3RtDNzmIGRu9xjV7fo7un0=
 github.com/onflow/flow-ft/lib/go/contracts v0.7.1-0.20230711213910-baad011d2b13/go.mod h1:kTMFIySzEJJeupk+7EmXs0EJ6CBWY/MV9fv9iYQk+RU=
 github.com/onflow/flow-go-sdk v0.24.0/go.mod h1:IoptMLPyFXWvyd9yYA6/4EmSeeozl6nJoIv4FaEMg74=

integration/go.mod

@@ -22,10 +22,10 @@ require (
 	github.com/onflow/cadence v0.42.5
 	github.com/onflow/flow-core-contracts/lib/go/contracts v1.2.4-0.20231016154253-a00dbf7c061f
 	github.com/onflow/flow-core-contracts/lib/go/templates v1.2.4-0.20231016154253-a00dbf7c061f
-	github.com/onflow/flow-emulator v0.54.1-0.20231110220143-28061d9b37e7
+	github.com/onflow/flow-emulator v0.58.0
 	github.com/onflow/flow-go v0.32.7
 	github.com/onflow/flow-go-sdk v0.41.16
-	github.com/onflow/flow-go/crypto v0.24.9
+	github.com/onflow/flow-go/crypto v0.24.10
 	github.com/onflow/flow-go/insecure v0.0.0-00010101000000-000000000000
 	github.com/onflow/flow/protobuf/go/flow v0.3.2-0.20231121210617-52ee94b830c2
 	github.com/plus3it/gorecurcopy v0.0.1
@@ -149,7 +149,7 @@ require (
 	github.com/google/uuid v1.3.1 // indirect
 	github.com/googleapis/enterprise-certificate-proxy v0.2.3 // indirect
 	github.com/googleapis/gax-go/v2 v2.11.0 // indirect
-	github.com/gorilla/mux v1.8.0 // indirect
+	github.com/gorilla/mux v1.8.1 // indirect
 	github.com/grpc-ecosystem/go-grpc-middleware/providers/zerolog/v2 v2.0.0-rc.2 // indirect
 	github.com/grpc-ecosystem/go-grpc-middleware/v2 v2.0.0-rc.2 // indirect
 	github.com/grpc-ecosystem/go-grpc-prometheus v1.2.0 // indirect
@@ -290,7 +290,7 @@ require (
 	github.com/spaolacci/murmur3 v1.1.0 // indirect
 	github.com/spf13/afero v1.9.3 // indirect
 	github.com/spf13/cast v1.5.0 // indirect
-	github.com/spf13/cobra v1.7.0 // indirect
+	github.com/spf13/cobra v1.8.0 // indirect
 	github.com/spf13/jwalterweatherman v1.1.0 // indirect
 	github.com/spf13/pflag v1.0.5 // indirect
 	github.com/spf13/viper v1.15.0 // indirect

integration/go.sum

@@ -302,6 +302,7 @@ github.com/cpuguy83/go-md2man v1.0.10/go.mod h1:SmD6nW6nTyfqj6ABTjUi3V3JVMnlJmwc
 github.com/cpuguy83/go-md2man/v2 v2.0.0-20190314233015-f79a8a8ca69d/go.mod h1:maD7wRr/U5Z6m/iR4s+kqSMx2CaBsrgA7czyZG/E6dU=
 github.com/cpuguy83/go-md2man/v2 v2.0.0/go.mod h1:maD7wRr/U5Z6m/iR4s+kqSMx2CaBsrgA7czyZG/E6dU=
 github.com/cpuguy83/go-md2man/v2 v2.0.2/go.mod h1:tgQtvFlXSQOSOSIRvRPT7W67SCa46tRHOmNcaadrF8o=
+github.com/cpuguy83/go-md2man/v2 v2.0.3/go.mod h1:tgQtvFlXSQOSOSIRvRPT7W67SCa46tRHOmNcaadrF8o=
 github.com/creack/pty v1.1.7/go.mod h1:lj5s0c3V2DBrqTV7llrYr5NG6My20zk30Fl46Y7DoTY=
 github.com/creack/pty v1.1.9/go.mod h1:oKZEueFk5CKHvIhNR5MUki03XCEU+Q6VDXinZuGJ33E=
 github.com/creack/pty v1.1.18 h1:n56/Zwd5o6whRC5PMGretI4IdRLlmBXYNjScPaBgsbY=
@@ -644,8 +645,9 @@ github.com/gopherjs/gopherjs v0.0.0-20190430165422-3e4dfb77656c h1:7lF+Vz0LqiRid
 github.com/gorilla/context v1.1.1/go.mod h1:kBGZzfjB9CEq2AlWe17Uuf7NDRt0dE0s8S51q0aT7Yg=
 github.com/gorilla/mux v1.6.2/go.mod h1:1lud6UwP+6orDFRuTfBEV8e9/aOM/c4fVVCaMa2zaAs=
 github.com/gorilla/mux v1.7.3/go.mod h1:1lud6UwP+6orDFRuTfBEV8e9/aOM/c4fVVCaMa2zaAs=
-github.com/gorilla/mux v1.8.0 h1:i40aqfkR1h2SlN9hojwV5ZA91wcXFOvkdNIeFDP5koI=
 github.com/gorilla/mux v1.8.0/go.mod h1:DVbg23sWSpFRCP0SfiEN6jmj59UnW/n46BH5rLB71So=
+github.com/gorilla/mux v1.8.1 h1:TuBL49tXwgrFYWhqrNgrUNEY92u81SPhu7sTdzQEiWY=
+github.com/gorilla/mux v1.8.1/go.mod h1:AKf9I4AEqPTmMytcMc0KkNouC66V3BtZ4qD5fmWSiMQ=
 github.com/gorilla/websocket v0.0.0-20170926233335-4201258b820c/go.mod h1:E7qHFY5m1UJ88s3WnNqhKjPHQ0heANvMoAMk2YaljkQ=
 github.com/gorilla/websocket v1.4.0/go.mod h1:E7qHFY5m1UJ88s3WnNqhKjPHQ0heANvMoAMk2YaljkQ=
 github.com/gorilla/websocket v1.4.1-0.20190629185528-ae1634f6a989/go.mod h1:E7qHFY5m1UJ88s3WnNqhKjPHQ0heANvMoAMk2YaljkQ=
@@ -1398,16 +1400,16 @@ github.com/onflow/flow-core-contracts/lib/go/contracts v1.2.4-0.20231016154253-a
 github.com/onflow/flow-core-contracts/lib/go/contracts v1.2.4-0.20231016154253-a00dbf7c061f/go.mod h1:jM6GMAL+m0hjusUgiYDNrixPQ6b9s8xjoJQoEu5bHQI=
 github.com/onflow/flow-core-contracts/lib/go/templates v1.2.4-0.20231016154253-a00dbf7c061f h1:Ep+Mpo2miWMe4pjPGIaEvEzshRep30dvNgxqk+//FrQ=
 github.com/onflow/flow-core-contracts/lib/go/templates v1.2.4-0.20231016154253-a00dbf7c061f/go.mod h1:ZeLxwaBkzuSInESGjL8/IPZWezF+YOYsYbMrZlhN+q4=
-github.com/onflow/flow-emulator v0.54.1-0.20231110220143-28061d9b37e7 h1:rMqbd3ZYtemFCdP/QvLbHloQn4+ZOakQrPMZdojvKpE=
-github.com/onflow/flow-emulator v0.54.1-0.20231110220143-28061d9b37e7/go.mod h1:AaHzJfv3jIanaty6RnSf0oEmvokSErtUsW8xotR2z2I=
+github.com/onflow/flow-emulator v0.58.0 h1:/Zo+qznjqN2jJNOGQu1mFK2lZT3L6c8V18AmAzXLKZ8=
+github.com/onflow/flow-emulator v0.58.0/go.mod h1:pi23Sx7kuj65dJRT7OIlio53XRAhLTUUhf3zV9TN3PA=
 github.com/onflow/flow-ft/lib/go/contracts v0.7.1-0.20230711213910-baad011d2b13 h1:B4ll7e3j+MqTJv2122Enq3RtDNzmIGRu9xjV7fo7un0=
 github.com/onflow/flow-ft/lib/go/contracts v0.7.1-0.20230711213910-baad011d2b13/go.mod h1:kTMFIySzEJJeupk+7EmXs0EJ6CBWY/MV9fv9iYQk+RU=
 github.com/onflow/flow-go-sdk v0.24.0/go.mod h1:IoptMLPyFXWvyd9yYA6/4EmSeeozl6nJoIv4FaEMg74=
 github.com/onflow/flow-go-sdk v0.41.16 h1:HsmHwEVmj+iK+GszHbFseHh7Ii5W3PWOIRNAH/En08Q=
 github.com/onflow/flow-go-sdk v0.41.16/go.mod h1:bVrVNoJKiwB6vW5Qbm5tFAfJBQ5we4uSQWnn9gNAFhQ=
 github.com/onflow/flow-go/crypto v0.21.3/go.mod h1:vI6V4CY3R6c4JKBxdcRiR/AnjBfL8OSD97bJc60cLuQ=
-github.com/onflow/flow-go/crypto v0.24.9 h1:0EQp+kSZYJepMIiSypfJVe7tzsPcb6UXOdOtsTCDhBs=
-github.com/onflow/flow-go/crypto v0.24.9/go.mod h1:fqCzkIBBMRRkciVrvW21rECKq1oD7Q6u+bCI78lfNX0=
+github.com/onflow/flow-go/crypto v0.24.10 h1:nH97tnnC0RaFXO5GuJic5lt/5IEiOuuWa3gaJI2Le3w=
+github.com/onflow/flow-go/crypto v0.24.10/go.mod h1:O7jjGhgJEp94t9qXfBWdwW5BArm5L5gYa6XoBJiTdHc=
 github.com/onflow/flow-nft/lib/go/contracts v1.1.0 h1:rhUDeD27jhLwOqQKI/23008CYfnqXErrJvc4EFRP2a0=
 github.com/onflow/flow-nft/lib/go/contracts v1.1.0/go.mod h1:YsvzYng4htDgRB9sa9jxdwoTuuhjK8WYWXTyLkIigZY=
 github.com/onflow/flow/protobuf/go/flow v0.2.2/go.mod h1:gQxYqCfkI8lpnKsmIjwtN2mV/N2PIwc1I+RUK4HPIc8=
@@ -1662,8 +1664,8 @@ github.com/spf13/cast v1.5.0 h1:rj3WzYc11XZaIZMPKmwP96zkFEnnAmV8s6XbB2aY32w=
 github.com/spf13/cast v1.5.0/go.mod h1:SpXXQ5YoyJw6s3/6cMTQuxvgRl3PCJiyaX9p6b155UU=
 github.com/spf13/cobra v0.0.3/go.mod h1:1l0Ry5zgKvJasoi3XT1TypsSe7PqH0Sj9dhYf7v3XqQ=
 github.com/spf13/cobra v0.0.5/go.mod h1:3K3wKZymM7VvHMDS9+Akkh4K60UwM26emMESw8tLCHU=
-github.com/spf13/cobra v1.7.0 h1:hyqWnYt1ZQShIddO5kBpj3vu05/++x6tJ6dg8EC572I=
-github.com/spf13/cobra v1.7.0/go.mod h1:uLxZILRyS/50WlhOIKD7W6V5bgeIt+4sICxh6uRMrb0=
+github.com/spf13/cobra v1.8.0 h1:7aJaZx1B85qltLMc546zn58BxxfZdR/W22ej9CFoEf0=
+github.com/spf13/cobra v1.8.0/go.mod h1:WXLWApfZ71AjXPya3WOlMsY9yMs7YeiHhFVlvLyhcho=
 github.com/spf13/jwalterweatherman v1.0.0/go.mod h1:cQK4TGJAtQXfYWX+Ddv3mKDzgVb68N+wFjFa4jdeBTo=
 github.com/spf13/jwalterweatherman v1.1.0 h1:ue6voC5bR5F8YxI5S67j9i582FU4Qvo2bmqnqMYADFk=
 github.com/spf13/jwalterweatherman v1.1.0/go.mod h1:aNWZUN0dPAAO/Ljvb5BEdw96iTZ0EXowPYD95IqWIGo=

model/convert/service_event.go

@@ -202,22 +202,25 @@ func convertServiceEventEpochSetup(event flow.Event) (*flow.ServiceEvent, error)
 		DKGPhase3FinalView: uint64(dkgPhase3FinalView),
 	}
 
-	// Cadence's unsafeRandom().toString() produces a string of variable length.
-	// Here we pad it with enough 0s to meet the required length.
-	paddedRandomSrcHex := fmt.Sprintf(
-		"%0*s",
-		2*flow.EpochSetupRandomSourceLength,
-		string(randomSrcHex),
-	)
-	setup.RandomSource, err = hex.DecodeString(paddedRandomSrcHex)
+	// random source from the event must be a hex string
+	// containing exactly 128 bits (equivalent to 16 bytes or 32 hex characters)
+	setup.RandomSource, err = hex.DecodeString(string(randomSrcHex))
 	if err != nil {
 		return nil, fmt.Errorf(
 			"could not decode random source hex (%v): %w",
-			paddedRandomSrcHex,
+			randomSrcHex,
 			err,
 		)
 	}
 
+	if len(setup.RandomSource) != flow.EpochSetupRandomSourceLength {
+		return nil, fmt.Errorf(
+			"random source in epoch setup event must be of (%d) bytes, got (%d)",
+			flow.EpochSetupRandomSourceLength,
+			len(setup.RandomSource),
+		)
+	}
+
 	// parse cluster assignments
 	setup.Assignments, err = convertClusterAssignments(cdcClusters.Values)
 	if err != nil {

model/convert/service_event_test.go

@@ -39,6 +39,21 @@ func TestEventConversion(t *testing.T) {
 		},
 	)
 
+	t.Run(
+		"epoch setup invalid random source", func(t *testing.T) {
+
+			fixture, _ := unittest.EpochSetupFixtureByChainID(chainID)
+			// update the random source in event fixture
+			randomSource := unittest.EpochSetupRandomSourceFixture()
+			fixture.Payload = unittest.EpochSetupFixtureCCF(randomSource[:flow.EpochSetupRandomSourceLength-1])
+
+			// convert Cadence types to Go types
+			event, err := convert.ServiceEvent(chainID, fixture)
+			require.Error(t, err)
+			require.Nil(t, event)
+		},
+	)
+
 	t.Run(
 		"epoch commit", func(t *testing.T) {
 

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 = "8476e9a47da2f993fd0d04efc10238113f217b0c037ccf903613088d51027d6a"
+const GenesisStateCommitmentHex = "436f6ac1de4738ed17405527dee7e639bc89600f329f6453d320311d84750211"
 
 var GenesisStateCommitment flow.StateCommitment
 

utils/unittest/service_events_fixtures.go

@@ -1,6 +1,9 @@
 package unittest
 
 import (
+	"crypto/rand"
+	"encoding/hex"
+
 	"github.com/onflow/cadence"
 	"github.com/onflow/cadence/encoding/ccf"
 	"github.com/onflow/cadence/runtime/common"
@@ -12,6 +15,15 @@ import (
 
 // This file contains service event fixtures for testing purposes.
 
+func EpochSetupRandomSourceFixture() []byte {
+	source := make([]byte, flow.EpochSetupRandomSourceLength)
+	_, err := rand.Read(source)
+	if err != nil {
+		panic(err)
+	}
+	return source
+}
+
 // EpochSetupFixtureByChainID returns an EpochSetup service event as a Cadence event
 // representation and as a protocol model representation.
 func EpochSetupFixtureByChainID(chain flow.ChainID) (flow.Event, *flow.EpochSetup) {
@@ -21,13 +33,8 @@ func EpochSetupFixtureByChainID(chain flow.ChainID) (flow.Event, *flow.EpochSetu
 	}
 
 	event := EventFixture(events.EpochSetup.EventType(), 1, 1, IdentifierFixture(), 0)
-	event.Payload = EpochSetupFixtureCCF
-
-	// randomSource is [0,0,...,1,2,3,4]
-	randomSource := make([]uint8, flow.EpochSetupRandomSourceLength)
-	for i := 0; i < 4; i++ {
-		randomSource[flow.EpochSetupRandomSourceLength-1-i] = uint8(4 - i)
-	}
+	randomSource := EpochSetupRandomSourceFixture()
+	event.Payload = EpochSetupFixtureCCF(randomSource)
 
 	expected := &flow.EpochSetup{
 		Counter:            1,
@@ -174,7 +181,8 @@ func VersionBeaconFixtureByChainID(chain flow.ChainID) (flow.Event, *flow.Versio
 	return event, expected
 }
 
-func createEpochSetupEvent() cadence.Event {
+func createEpochSetupEvent(randomSource []byte) cadence.Event {
+	randomSourceHex := hex.EncodeToString(randomSource)
 
 	return cadence.NewEvent([]cadence.Value{
 		// counter
@@ -193,7 +201,7 @@ func createEpochSetupEvent() cadence.Event {
 		createEpochCollectors(),
 
 		// randomSource
-		cadence.String("01020304"),
+		cadence.String(randomSourceHex),
 
 		// DKGPhase1FinalView
 		cadence.UInt64(150),
@@ -1028,8 +1036,8 @@ func ufix64FromString(s string) cadence.UFix64 {
 	return f
 }
 
-var EpochSetupFixtureCCF = func() []byte {
-	b, err := ccf.Encode(createEpochSetupEvent())
+func EpochSetupFixtureCCF(randomSource []byte) []byte {
+	b, err := ccf.Encode(createEpochSetupEvent(randomSource))
 	if err != nil {
 		panic(err)
 	}
@@ -1038,7 +1046,7 @@ var EpochSetupFixtureCCF = func() []byte {
 		panic(err)
 	}
 	return b
-}()
+}
 
 var EpochCommitFixtureCCF = func() []byte {
 	b, err := ccf.Encode(createEpochCommittedEvent())