Added randomized simulation parameters generation (#389)

* added simulation params * fixed return types * implemented full sim test on wasmd * removed wrong committed github action * switched to a import export test since i'm introducing params and genesis simulations * fixed makefile * Fixed sim test flags not working * fixed some errors on sim test * fixed conflicts still a failure to be solved * fixed wasm params error * added missing codec * Update params.go removed unused import * fixed intellij cache errors * added full app simulation test that pass * added README.md for sims credits added me into contributors list Co-authored-by: riccardo.montagnin <riccardo.montagnin@gmail.com>
2021-02-05 13:19:14 +01:00
parent a278049dc0
commit d0befd973d
10 changed files with 423 additions and 7 deletions
--- a/15
+++ b/15
@@ -5,6 +5,8 @@ VERSION := $(shell echo $(shell git describe --tags) | sed 's/^v//')
 COMMIT := $(shell git log -1 --format='%H')
 LEDGER_ENABLED ?= true
 SDK_PACK := $(shell go list -m github.com/cosmos/cosmos-sdk | sed  's/ /\@/g')
+BINDIR ?= $(GOPATH)/bin
+SIMAPP = ./app

 # for dockerized protobuf tools
 PROTO_CONTAINER := cosmwasm/prototools-docker:v0.1.0
@@ -94,6 +96,9 @@ BUILD_FLAGS := -tags "$(build_tags_comma_sep)" -ldflags '$(ldflags)' -trimpath
 CORAL_BUILD_FLAGS := -tags "$(build_tags_comma_sep)" -ldflags '$(coral_ldflags)' -trimpath
 FLEX_BUILD_FLAGS := -tags "$(build_tags_comma_sep)" -ldflags '$(flex_ldflags)' -trimpath

+# The below include contains the tools and runsim targets.
+include contrib/devtools/Makefile
+
 all: install lint test

 build: go.sum
@@ -172,6 +177,13 @@ test-cover:
 benchmark:
 	@go test -mod=readonly -bench=. ./...

+test-sim-import-export: runsim
+	@echo "Running application import/export simulation. This may take several minutes..."
+	@$(BINDIR)/runsim -Jobs=4 -SimAppPkg=$(SIMAPP) -ExitOnFail 50 5 TestAppImportExport
+
+test-sim-multi-seed-short: runsim
+	@echo "Running short multi-seed application simulation. This may take awhile!"
+	@$(BINDIR)/runsim -Jobs=4 -SimAppPkg=$(SIMAPP) -ExitOnFail 50 10 TestFullAppSimulation

 ###############################################################################
 ###                                Linting                                  ###
@@ -208,4 +220,5 @@ proto-check-breaking:

 .PHONY: all build-linux install install-debug \
 	go-mod-cache draw-deps clean build format \
-	test test-all test-build test-cover test-unit test-race
+	test test-all test-build test-cover test-unit test-race \
+	test-sim-import-export \
--- a/README.md
+++ b/README.md
@@ -209,5 +209,6 @@ Or even testing the app and bringing up critical issues. The following have help
 * Rick Dudley [AFDudley](https://github.com/AFDudley)
 * KamiD [KamiD](https://github.com/KamiD)
 * Valery Litvin [litvintech](https://github.com/litvintech)
+* Leonardo Bragagnolo [bragaz](https://github.com/bragaz)

 Sorry if I forgot you from this list, just contact me or add yourself in a PR :)
--- a/app/app.go
+++ b/app/app.go
@@ -417,7 +417,7 @@ func NewWasmApp(logger log.Logger, db dbm.DB, traceStore io.Writer, loadLatest b
 		distr.NewAppModule(appCodec, app.distrKeeper, app.accountKeeper, app.bankKeeper, app.stakingKeeper),
 		staking.NewAppModule(appCodec, app.stakingKeeper, app.accountKeeper, app.bankKeeper),
 		upgrade.NewAppModule(app.upgradeKeeper),
-		wasm.NewAppModule(&app.wasmKeeper, app.stakingKeeper),
+		wasm.NewAppModule(appCodec, &app.wasmKeeper, app.stakingKeeper),
 		evidence.NewAppModule(app.evidenceKeeper),
 		ibc.NewAppModule(app.ibcKeeper),
 		params.NewAppModule(app.paramsKeeper),
@@ -469,7 +469,7 @@ func NewWasmApp(logger log.Logger, db dbm.DB, traceStore io.Writer, loadLatest b
 		distr.NewAppModule(appCodec, app.distrKeeper, app.accountKeeper, app.bankKeeper, app.stakingKeeper),
 		slashing.NewAppModule(appCodec, app.slashingKeeper, app.accountKeeper, app.bankKeeper, app.stakingKeeper),
 		params.NewAppModule(app.paramsKeeper),
-		wasm.NewAppModule(&app.wasmKeeper, app.stakingKeeper),
+		wasm.NewAppModule(appCodec, &app.wasmKeeper, app.stakingKeeper),
 		evidence.NewAppModule(app.evidenceKeeper),
 		ibc.NewAppModule(app.ibcKeeper),
 		transferModule,
@@ -616,6 +616,10 @@ func (app *WasmApp) RegisterTendermintService(clientCtx client.Context) {
 	tmservice.RegisterTendermintService(app.BaseApp.GRPCQueryRouter(), clientCtx, app.interfaceRegistry)
 }

+func (app *WasmApp) AppCodec() codec.JSONMarshaler {
+	return app.appCodec
+}
+
 // RegisterSwaggerAPI registers swagger route with API Server
 func RegisterSwaggerAPI(_ client.Context, rtr *mux.Router) {
 	statikFS, err := fs.New()
--- a/app/sim_test.go
+++ b/app/sim_test.go
@@ -0,0 +1,230 @@
+package app
+
+import (
+	"encoding/json"
+	"fmt"
+	"github.com/CosmWasm/wasmd/x/wasm"
+	"github.com/cosmos/cosmos-sdk/baseapp"
+	"github.com/cosmos/cosmos-sdk/simapp"
+	sdk "github.com/cosmos/cosmos-sdk/types"
+	"github.com/cosmos/cosmos-sdk/types/kv"
+	simtypes "github.com/cosmos/cosmos-sdk/types/simulation"
+	authtypes "github.com/cosmos/cosmos-sdk/x/auth/types"
+	banktypes "github.com/cosmos/cosmos-sdk/x/bank/types"
+	capabilitytypes "github.com/cosmos/cosmos-sdk/x/capability/types"
+	distrtypes "github.com/cosmos/cosmos-sdk/x/distribution/types"
+	evidencetypes "github.com/cosmos/cosmos-sdk/x/evidence/types"
+	govtypes "github.com/cosmos/cosmos-sdk/x/gov/types"
+	ibctransfertypes "github.com/cosmos/cosmos-sdk/x/ibc/applications/transfer/types"
+	ibchost "github.com/cosmos/cosmos-sdk/x/ibc/core/24-host"
+	minttypes "github.com/cosmos/cosmos-sdk/x/mint/types"
+	paramstypes "github.com/cosmos/cosmos-sdk/x/params/types"
+	"github.com/cosmos/cosmos-sdk/x/simulation"
+	slashingtypes "github.com/cosmos/cosmos-sdk/x/slashing/types"
+	stakingtypes "github.com/cosmos/cosmos-sdk/x/staking/types"
+	"github.com/stretchr/testify/require"
+	"github.com/tendermint/tendermint/libs/log"
+	tmproto "github.com/tendermint/tendermint/proto/tendermint/types"
+	dbm "github.com/tendermint/tm-db"
+	"os"
+	"path/filepath"
+	"testing"
+)
+
+// Get flags every time the simulator is run
+func init() {
+	simapp.GetSimulatorFlags()
+}
+
+type StoreKeysPrefixes struct {
+	A        sdk.StoreKey
+	B        sdk.StoreKey
+	Prefixes [][]byte
+}
+
+// SetupSimulation wraps simapp.SetupSimulation in order to create any export directory if they do not exist yet
+func SetupSimulation(dirPrefix, dbName string) (simtypes.Config, dbm.DB, string, log.Logger, bool, error) {
+	config, db, dir, logger, skip, err := simapp.SetupSimulation(dirPrefix, dbName)
+	if err != nil {
+		return simtypes.Config{}, nil, "", nil, false, err
+	}
+
+	paths := []string{config.ExportParamsPath, config.ExportStatePath, config.ExportStatsPath}
+	for _, path := range paths {
+		if len(path) == 0 {
+			continue
+		}
+
+		path = filepath.Dir(path)
+		if _, err := os.Stat(path); os.IsNotExist(err) {
+			if err := os.MkdirAll(path, os.ModePerm); err != nil {
+				panic(err)
+			}
+		}
+	}
+
+	return config, db, dir, logger, skip, err
+}
+
+// GetSimulationLog unmarshals the KVPair's Value to the corresponding type based on the
+// each's module store key and the prefix bytes of the KVPair's key.
+func GetSimulationLog(storeName string, sdr sdk.StoreDecoderRegistry, kvAs, kvBs []kv.Pair) (log string) {
+	for i := 0; i < len(kvAs); i++ {
+		if len(kvAs[i].Value) == 0 && len(kvBs[i].Value) == 0 {
+			// skip if the value doesn't have any bytes
+			continue
+		}
+
+		decoder, ok := sdr[storeName]
+		if ok {
+			log += decoder(kvAs[i], kvBs[i])
+		} else {
+			log += fmt.Sprintf("store A %s => %s\nstore B %s => %s\n", kvAs[i].Key, kvAs[i].Value, kvBs[i].Key, kvBs[i].Value)
+		}
+	}
+
+	return log
+}
+
+// fauxMerkleModeOpt returns a BaseApp option to use a dbStoreAdapter instead of
+// an IAVLStore for faster simulation speed.
+func fauxMerkleModeOpt(bapp *baseapp.BaseApp) {
+	bapp.SetFauxMerkleMode()
+}
+
+func TestAppImportExport(t *testing.T) {
+	config, db, dir, logger, skip, err := SetupSimulation("leveldb-app-sim", "Simulation")
+	if skip {
+		t.Skip("skipping application import/export simulation")
+	}
+	require.NoError(t, err, "simulation setup failed")
+
+	defer func() {
+		db.Close()
+		require.NoError(t, os.RemoveAll(dir))
+	}()
+
+	app := NewWasmApp(logger, db, nil, true, map[int64]bool{}, DefaultNodeHome, simapp.FlagPeriodValue, wasm.EnableAllProposals, EmptyBaseAppOptions{}, nil, fauxMerkleModeOpt)
+	require.Equal(t, appName, app.Name())
+
+	// Run randomized simulation
+	_, simParams, simErr := simulation.SimulateFromSeed(
+		t,
+		os.Stdout,
+		app.BaseApp,
+		simapp.AppStateFn(app.AppCodec(), app.SimulationManager()),
+		simtypes.RandomAccounts,
+		simapp.SimulationOperations(app, app.AppCodec(), config),
+		app.ModuleAccountAddrs(),
+		config,
+		app.AppCodec(),
+	)
+
+	// export state and simParams before the simulation error is checked
+	err = simapp.CheckExportSimulation(app, config, simParams)
+	require.NoError(t, err)
+	require.NoError(t, simErr)
+
+	if config.Commit {
+		simapp.PrintStats(db)
+	}
+
+	fmt.Printf("exporting genesis...\n")
+
+	exported, err := app.ExportAppStateAndValidators(false, []string{})
+	require.NoError(t, err)
+
+	fmt.Printf("importing genesis...\n")
+
+	_, newDB, newDir, _, _, err := SetupSimulation("leveldb-app-sim-2", "Simulation-2")
+	require.NoError(t, err, "simulation setup failed")
+
+	defer func() {
+		newDB.Close()
+		require.NoError(t, os.RemoveAll(newDir))
+	}()
+
+	newApp := NewWasmApp(logger, db, nil, true, map[int64]bool{}, DefaultNodeHome, simapp.FlagPeriodValue, wasm.EnableAllProposals, EmptyBaseAppOptions{}, nil, fauxMerkleModeOpt)
+	require.Equal(t, appName, newApp.Name())
+
+	var genesisState GenesisState
+	err = json.Unmarshal(exported.AppState, &genesisState)
+	require.NoError(t, err)
+
+	ctxA := app.NewContext(true, tmproto.Header{Height: app.LastBlockHeight()})
+	ctxB := newApp.NewContext(true, tmproto.Header{Height: app.LastBlockHeight()})
+	newApp.mm.InitGenesis(ctxB, app.AppCodec(), genesisState)
+	newApp.StoreConsensusParams(ctxB, exported.ConsensusParams)
+
+	fmt.Printf("comparing stores...\n")
+
+	storeKeysPrefixes := []StoreKeysPrefixes{
+		{app.keys[authtypes.StoreKey], newApp.keys[authtypes.StoreKey], [][]byte{}},
+		{app.keys[stakingtypes.StoreKey], newApp.keys[stakingtypes.StoreKey],
+			[][]byte{
+				stakingtypes.UnbondingQueueKey, stakingtypes.RedelegationQueueKey, stakingtypes.ValidatorQueueKey,
+				stakingtypes.HistoricalInfoKey,
+			}},
+		{app.keys[slashingtypes.StoreKey], newApp.keys[slashingtypes.StoreKey], [][]byte{}},
+		{app.keys[minttypes.StoreKey], newApp.keys[minttypes.StoreKey], [][]byte{}},
+		{app.keys[distrtypes.StoreKey], newApp.keys[distrtypes.StoreKey], [][]byte{}},
+		{app.keys[banktypes.StoreKey], newApp.keys[banktypes.StoreKey], [][]byte{banktypes.BalancesPrefix}},
+		{app.keys[paramstypes.StoreKey], newApp.keys[paramstypes.StoreKey], [][]byte{}},
+		{app.keys[govtypes.StoreKey], newApp.keys[govtypes.StoreKey], [][]byte{}},
+		{app.keys[evidencetypes.StoreKey], newApp.keys[evidencetypes.StoreKey], [][]byte{}},
+		{app.keys[capabilitytypes.StoreKey], newApp.keys[capabilitytypes.StoreKey], [][]byte{}},
+		{app.keys[ibchost.StoreKey], newApp.keys[ibchost.StoreKey], [][]byte{}},
+		{app.keys[ibctransfertypes.StoreKey], newApp.keys[ibctransfertypes.StoreKey], [][]byte{}},
+		{app.keys[wasm.StoreKey], newApp.keys[wasm.StoreKey], [][]byte{}},
+	}
+
+	for _, skp := range storeKeysPrefixes {
+		storeA := ctxA.KVStore(skp.A)
+		storeB := ctxB.KVStore(skp.B)
+
+		failedKVAs, failedKVBs := sdk.DiffKVStores(storeA, storeB, skp.Prefixes)
+		require.Equal(t, len(failedKVAs), len(failedKVBs), "unequal sets of key-values to compare")
+
+		fmt.Printf("compared %d different key/value pairs between %s and %s\n", len(failedKVAs), skp.A, skp.B)
+		require.Len(t, failedKVAs, 0, GetSimulationLog(skp.A.Name(), app.SimulationManager().StoreDecoders, failedKVAs, failedKVBs))
+	}
+}
+
+func TestFullAppSimulation(t *testing.T) {
+	config, db, dir, logger, skip, err := SetupSimulation("leveldb-app-sim", "Simulation")
+	if skip {
+		t.Skip("skipping application simulation")
+	}
+	require.NoError(t, err, "simulation setup failed")
+
+	defer func() {
+		db.Close()
+		require.NoError(t, os.RemoveAll(dir))
+	}()
+
+	app := NewWasmApp(logger, db, nil, true, map[int64]bool{}, DefaultNodeHome, simapp.FlagPeriodValue,
+		wasm.EnableAllProposals, simapp.EmptyAppOptions{}, nil, fauxMerkleModeOpt)
+	require.Equal(t, "WasmApp", app.Name())
+
+	// run randomized simulation
+	_, simParams, simErr := simulation.SimulateFromSeed(
+		t,
+		os.Stdout,
+		app.BaseApp,
+		simapp.AppStateFn(app.appCodec, app.SimulationManager()),
+		simtypes.RandomAccounts, // Replace with own random account function if using keys other than secp256k1
+		simapp.SimulationOperations(app, app.AppCodec(), config),
+		app.ModuleAccountAddrs(),
+		config,
+		app.AppCodec(),
+	)
+
+	// export state and simParams before the simulation error is checked
+	err = simapp.CheckExportSimulation(app, config, simParams)
+	require.NoError(t, err)
+	require.NoError(t, simErr)
+
+	if config.Commit {
+		simapp.PrintStats(db)
+	}
+}
--- a/contrib/devtools/Makefile
+++ b/contrib/devtools/Makefile
@@ -0,0 +1,85 @@
+###
+# Find OS and Go environment
+# GO contains the Go binary
+# FS contains the OS file separator
+###
+ifeq ($(OS),Windows_NT)
+  GO := $(shell where go.exe 2> NUL)
+  FS := "\\"
+else
+  GO := $(shell command -v go 2> /dev/null)
+  FS := "/"
+endif
+
+ifeq ($(GO),)
+  $(error could not find go. Is it in PATH? $(GO))
+endif
+
+###############################################################################
+###                                Functions                                ###
+###############################################################################
+
+go_get = $(if $(findstring Windows_NT,$(OS)),\
+IF NOT EXIST $(GITHUBDIR)$(FS)$(1)$(FS) ( mkdir $(GITHUBDIR)$(FS)$(1) ) else (cd .) &\
+IF NOT EXIST $(GITHUBDIR)$(FS)$(1)$(FS)$(2)$(FS) ( cd $(GITHUBDIR)$(FS)$(1) && git clone https://github.com/$(1)/$(2) ) else (cd .) &\
+,\
+mkdir -p $(GITHUBDIR)$(FS)$(1) &&\
+(test ! -d $(GITHUBDIR)$(FS)$(1)$(FS)$(2) && cd $(GITHUBDIR)$(FS)$(1) && git clone https://github.com/$(1)/$(2)) || true &&\
+)\
+cd $(GITHUBDIR)$(FS)$(1)$(FS)$(2) && git fetch origin && git checkout -q $(3)
+
+mkfile_path := $(abspath $(lastword $(MAKEFILE_LIST)))
+mkfile_dir := $(shell cd $(shell dirname $(mkfile_path)); pwd)
+
+
+###############################################################################
+###                                 Tools                                   ###
+###############################################################################
+
+PREFIX ?= /usr/local
+BIN ?= $(PREFIX)/bin
+UNAME_S ?= $(shell uname -s)
+UNAME_M ?= $(shell uname -m)
+
+GOPATH ?= $(shell $(GO) env GOPATH)
+GITHUBDIR := $(GOPATH)$(FS)src$(FS)github.com
+
+BUF_VERSION ?= 0.11.0
+
+TOOLS_DESTDIR  ?= $(GOPATH)/bin
+STATIK         = $(TOOLS_DESTDIR)/statik
+RUNSIM         = $(TOOLS_DESTDIR)/runsim
+GOLANGCI_LINT  = $(TOOLS_DESTDIR)/golangci-lint
+
+tools: tools-stamp
+tools-stamp: statik runsim golangci-lint
+	# Create dummy file to satisfy dependency and avoid
+	# rebuilding when this Makefile target is hit twice
+	# in a row.
+	touch $@
+
+statik: $(STATIK)
+$(STATIK):
+	@echo "Installing statik..."
+	@(cd /tmp && go get github.com/rakyll/statik@v0.1.6)
+
+# Install the runsim binary with a temporary workaround of entering an outside
+# directory as the "go get" command ignores the -mod option and will polute the
+# go.{mod, sum} files.
+#
+# ref: https://github.com/golang/go/issues/30515
+runsim: $(RUNSIM)
+$(RUNSIM):
+	@echo "Installing runsim..."
+	@(cd /tmp && go get github.com/cosmos/tools/cmd/runsim@v1.0.0)
+
+golangci-lint: $(GOLANGCI_LINT)
+$(GOLANGCI_LINT):
+	@echo "Installing golangci-lint..."
+	@(cd /tmp && go get github.com/golangci/golangci-lint/cmd/golangci-lint@v1.28.0)
+
+tools-clean:
+	rm -f $(STATIK) $(GOLANGCI_LINT) $(RUNSIM)
+	rm -f tools-stamp
+
+.PHONY: tools-clean statik runsim
--- a/contrib/devtools/README.md
+++ b/contrib/devtools/README.md
@@ -0,0 +1,6 @@
+## Contributors
+
+Thanks to the entire Cosmos SDK team and the contributors who put their efforts into making simulation testing
+easier to implement. 🤗
+
+https://github.com/cosmos/cosmos-sdk/blob/master/contrib/devtools/Makefile
--- a/x/wasm/module.go
+++ b/x/wasm/module.go
@@ -9,6 +9,7 @@ import (
 	"github.com/CosmWasm/wasmd/x/wasm/client/rest"
 	"github.com/CosmWasm/wasmd/x/wasm/internal/keeper"
 	"github.com/CosmWasm/wasmd/x/wasm/internal/types"
+	"github.com/CosmWasm/wasmd/x/wasm/simulation"
 	"github.com/cosmos/cosmos-sdk/client"
 	"github.com/cosmos/cosmos-sdk/codec"
 	cdctypes "github.com/cosmos/cosmos-sdk/codec/types"
@@ -94,14 +95,16 @@ func (b AppModuleBasic) RegisterInterfaces(registry cdctypes.InterfaceRegistry)
 // AppModule implements an application module for the wasm module.
 type AppModule struct {
 	AppModuleBasic
+	cdc                codec.Marshaler
 	keeper             *Keeper
 	validatorSetSource keeper.ValidatorSetSource
 }

 // NewAppModule creates a new AppModule object
-func NewAppModule(keeper *Keeper, validatorSetSource keeper.ValidatorSetSource) AppModule {
+func NewAppModule(cdc codec.Marshaler, keeper *Keeper, validatorSetSource keeper.ValidatorSetSource) AppModule {
 	return AppModule{
 		AppModuleBasic:     AppModuleBasic{},
+		cdc:                cdc,
 		keeper:             keeper,
 		validatorSetSource: validatorSetSource,
 	}
@@ -163,6 +166,7 @@ func (AppModule) EndBlock(_ sdk.Context, _ abci.RequestEndBlock) []abci.Validato

 // GenerateGenesisState creates a randomized GenState of the bank module.
 func (AppModule) GenerateGenesisState(simState *module.SimulationState) {
+	simulation.RandomizedGenState(simState)
 }

 // ProposalContents doesn't return any content functions for governance proposals.
@@ -171,8 +175,8 @@ func (AppModule) ProposalContents(simState module.SimulationState) []simtypes.We
 }

 // RandomizedParams creates randomized bank param changes for the simulator.
-func (AppModule) RandomizedParams(r *rand.Rand) []simtypes.ParamChange {
-	return nil
+func (am AppModule) RandomizedParams(r *rand.Rand) []simtypes.ParamChange {
+	return simulation.ParamChanges(r, am.cdc)
 }

 // RegisterStoreDecoder registers a decoder for supply module's types
--- a/x/wasm/module_test.go
+++ b/x/wasm/module_test.go
@@ -34,8 +34,9 @@ type testData struct {
 // returns a cleanup function, which must be defered on
 func setupTest(t *testing.T) testData {
 	ctx, keepers := CreateTestInput(t, false, "staking,stargate", nil, nil)
+	cdc := keeper.MakeTestCodec(t)
 	data := testData{
-		module:        NewAppModule(keepers.WasmKeeper, keepers.StakingKeeper),
+		module:        NewAppModule(cdc, keepers.WasmKeeper, keepers.StakingKeeper),
 		ctx:           ctx,
 		acctKeeper:    keepers.AccountKeeper,
 		keeper:        *keepers.WasmKeeper,
--- a/x/wasm/simulation/genesis.go
+++ b/x/wasm/simulation/genesis.go
@@ -0,0 +1,25 @@
+package simulation
+
+import (
+	"github.com/CosmWasm/wasmd/x/wasm/internal/types"
+	"github.com/cosmos/cosmos-sdk/types/module"
+)
+
+// RandomizeGenState generates a random GenesisState for wasm
+func RandomizedGenState(simstate *module.SimulationState) {
+	params := RandomParams(simstate.Rand)
+	wasmGenesis := types.GenesisState{
+		Params:    params,
+		Codes:     nil,
+		Contracts: nil,
+		Sequences: nil,
+		GenMsgs:   nil,
+	}
+
+	_, err := simstate.Cdc.MarshalJSON(&wasmGenesis)
+	if err != nil {
+		panic(err)
+	}
+
+	simstate.GenState[types.ModuleName] = simstate.Cdc.MustMarshalJSON(&wasmGenesis)
+}
--- a/x/wasm/simulation/params.go
+++ b/x/wasm/simulation/params.go
@@ -0,0 +1,47 @@
+package simulation
+
+import (
+	"fmt"
+	"math/rand"
+
+	"github.com/CosmWasm/wasmd/x/wasm/internal/types"
+	"github.com/cosmos/cosmos-sdk/codec"
+	simtypes "github.com/cosmos/cosmos-sdk/types/simulation"
+	"github.com/cosmos/cosmos-sdk/x/simulation"
+)
+
+func ParamChanges(r *rand.Rand, cdc codec.Marshaler) []simtypes.ParamChange {
+	params := RandomParams(r)
+	return []simtypes.ParamChange{
+		simulation.NewSimParamChange(types.ModuleName, string(types.ParamStoreKeyUploadAccess),
+			func(r *rand.Rand) string {
+				jsonBz, err := cdc.MarshalJSON(&params.CodeUploadAccess)
+				if err != nil {
+					panic(err)
+				}
+				return string(jsonBz)
+			},
+		),
+		simulation.NewSimParamChange(types.ModuleName, string(types.ParamStoreKeyInstantiateAccess),
+			func(r *rand.Rand) string {
+				return fmt.Sprintf("%q", params.CodeUploadAccess.Permission.String())
+			},
+		),
+		simulation.NewSimParamChange(types.ModuleName, string(types.ParamStoreKeyMaxWasmCodeSize),
+			func(r *rand.Rand) string {
+				return fmt.Sprintf(`"%d"`, params.MaxWasmCodeSize)
+			},
+		),
+	}
+}
+
+func RandomParams(r *rand.Rand) types.Params {
+	permissionType := types.AccessType(simtypes.RandIntBetween(r, 1, 3))
+	account, _ := simtypes.RandomAcc(r, simtypes.RandomAccounts(r, 10))
+	accessConfig := permissionType.With(account.Address)
+	return types.Params{
+		CodeUploadAccess:             accessConfig,
+		InstantiateDefaultPermission: accessConfig.Permission,
+		MaxWasmCodeSize:              uint64(simtypes.RandIntBetween(r, 1, 600) * 1024),
+	}
+}