Merge PR #4906: Introduce Simulation Config

simapp/state.go

@@ -0,0 +1,142 @@
+package simapp
+
+// DONTCOVER
+
+import (
+	"encoding/json"
+	"fmt"
+	"io/ioutil"
+	"math/rand"
+	"time"
+
+	"github.com/tendermint/tendermint/crypto/secp256k1"
+	tmtypes "github.com/tendermint/tendermint/types"
+
+	"github.com/cosmos/cosmos-sdk/x/genaccounts"
+	"github.com/cosmos/cosmos-sdk/x/simulation"
+)
+
+// AppStateFn returns the initial application state using a genesis or the simulation parameters.
+// It panics if the user provides files for both of them.
+// If a file is not given for the genesis or the sim params, it creates a randomized one.
+func AppStateFn(
+	r *rand.Rand, accs []simulation.Account, config simulation.Config,
+) (appState json.RawMessage, simAccs []simulation.Account, chainID string, genesisTimestamp time.Time) {
+
+	cdc := MakeCodec()
+
+	if flagGenesisTimeValue == 0 {
+		genesisTimestamp = simulation.RandTimestamp(r)
+	} else {
+		genesisTimestamp = time.Unix(flagGenesisTimeValue, 0)
+	}
+
+	switch {
+	case config.ParamsFile != "" && config.GenesisFile != "":
+		panic("cannot provide both a genesis file and a params file")
+
+	case config.GenesisFile != "":
+		appState, simAccs, chainID = AppStateFromGenesisFileFn(r, config)
+
+	case config.ParamsFile != "":
+		appParams := make(simulation.AppParams)
+		bz, err := ioutil.ReadFile(config.ParamsFile)
+		if err != nil {
+			panic(err)
+		}
+
+		cdc.MustUnmarshalJSON(bz, &appParams)
+		appState, simAccs, chainID = AppStateRandomizedFn(r, accs, genesisTimestamp, appParams)
+
+	default:
+		appParams := make(simulation.AppParams)
+		appState, simAccs, chainID = AppStateRandomizedFn(r, accs, genesisTimestamp, appParams)
+	}
+
+	return appState, simAccs, chainID, genesisTimestamp
+}
+
+// AppStateRandomizedFn creates calls each module's GenesisState generator function
+// and creates
+func AppStateRandomizedFn(
+	r *rand.Rand, accs []simulation.Account, genesisTimestamp time.Time, appParams simulation.AppParams,
+) (json.RawMessage, []simulation.Account, string) {
+
+	cdc := MakeCodec()
+	genesisState := NewDefaultGenesisState()
+
+	var (
+		amount             int64
+		numInitiallyBonded int64
+	)
+
+	appParams.GetOrGenerate(cdc, StakePerAccount, &amount, r,
+		func(r *rand.Rand) { amount = int64(r.Intn(1e12)) })
+	appParams.GetOrGenerate(cdc, InitiallyBondedValidators, &amount, r,
+		func(r *rand.Rand) { numInitiallyBonded = int64(r.Intn(250)) })
+
+	numAccs := int64(len(accs))
+	if numInitiallyBonded > numAccs {
+		numInitiallyBonded = numAccs
+	}
+
+	fmt.Printf(
+		`Selected randomly generated parameters for simulated genesis:
+{
+  stake_per_account: "%v",
+  initially_bonded_validators: "%v"
+}
+`, amount, numInitiallyBonded,
+	)
+
+	GenGenesisAccounts(cdc, r, accs, genesisTimestamp, amount, numInitiallyBonded, genesisState)
+	GenAuthGenesisState(cdc, r, appParams, genesisState)
+	GenBankGenesisState(cdc, r, appParams, genesisState)
+	GenSupplyGenesisState(cdc, amount, numInitiallyBonded, int64(len(accs)), genesisState)
+	GenGovGenesisState(cdc, r, appParams, genesisState)
+	GenMintGenesisState(cdc, r, appParams, genesisState)
+	GenDistrGenesisState(cdc, r, appParams, genesisState)
+	stakingGen := GenStakingGenesisState(cdc, r, accs, amount, numAccs, numInitiallyBonded, appParams, genesisState)
+	GenSlashingGenesisState(cdc, r, stakingGen, appParams, genesisState)
+
+	appState, err := MakeCodec().MarshalJSON(genesisState)
+	if err != nil {
+		panic(err)
+	}
+
+	return appState, accs, "simulation"
+}
+
+// AppStateFromGenesisFileFn util function to generate the genesis AppState
+// from a genesis.json file
+func AppStateFromGenesisFileFn(r *rand.Rand, config simulation.Config) (json.RawMessage, []simulation.Account, string) {
+
+	var genesis tmtypes.GenesisDoc
+	cdc := MakeCodec()
+
+	bytes, err := ioutil.ReadFile(config.GenesisFile)
+	if err != nil {
+		panic(err)
+	}
+
+	cdc.MustUnmarshalJSON(bytes, &genesis)
+
+	var appState GenesisState
+	cdc.MustUnmarshalJSON(genesis.AppState, &appState)
+
+	accounts := genaccounts.GetGenesisStateFromAppState(cdc, appState)
+
+	var newAccs []simulation.Account
+	for _, acc := range accounts {
+		// Pick a random private key, since we don't know the actual key
+		// This should be fine as it's only used for mock Tendermint validators
+		// and these keys are never actually used to sign by mock Tendermint.
+		privkeySeed := make([]byte, 15)
+		r.Read(privkeySeed)
+
+		privKey := secp256k1.GenPrivKeySecp256k1(privkeySeed)
+		newAccs = append(newAccs, simulation.Account{privKey, privKey.PubKey(), acc.Address})
+	}
+
+	return genesis.AppState, newAccs, genesis.ChainID
+}