genesis.go

package simapp

import (
	"encoding/json"
	"io"
	"io/ioutil"

	"github.com/cosmos/cosmos-sdk/codec"
	"github.com/cosmos/cosmos-sdk/crypto/keys/secp256k1"
	simtypes "github.com/cosmos/cosmos-sdk/types/simulation"
	authtypes "github.com/cosmos/cosmos-sdk/x/auth/types"
	tmjson "github.com/tendermint/tendermint/libs/json"
	tmtypes "github.com/tendermint/tendermint/types"
)

// AppStateFromGenesisFileFn util function to generate the genesis AppState
// from a genesis.json file.
func AppStateFromGenesisFileFn(r io.Reader, cdc codec.JSONCodec, genesisFile string) (tmtypes.GenesisDoc, []simtypes.Account) {
	bytes, err := ioutil.ReadFile(genesisFile)
	if err != nil {
		panic(err)
	}

	var genesis tmtypes.GenesisDoc
	// NOTE: Tendermint uses a custom JSON decoder for GenesisDoc
	err = tmjson.Unmarshal(bytes, &genesis)
	if err != nil {
		panic(err)
	}

	var appState GenesisState
	err = json.Unmarshal(genesis.AppState, &appState)
	if err != nil {
		panic(err)
	}

	var authGenesis authtypes.GenesisState
	if appState[authtypes.ModuleName] != nil {
		cdc.MustUnmarshalJSON(appState[authtypes.ModuleName], &authGenesis)
	}

	newAccs := make([]simtypes.Account, len(authGenesis.Accounts))
	for i, acc := range authGenesis.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)
		if _, err := r.Read(privkeySeed); err != nil {
			panic(err)
		}

		privKey := secp256k1.GenPrivKeyFromSecret(privkeySeed)

		a, ok := acc.GetCachedValue().(authtypes.AccountI)
		if !ok {
			panic("expected account")
		}

		// create simulator accounts
		simAcc := simtypes.Account{PrivKey: privKey, PubKey: privKey.PubKey(), Address: a.GetAddress()}
		newAccs[i] = simAcc
	}

	return genesis, newAccs
}

// GenesisState of the blockchain is represented here as a map of raw json
// messages key'd by a identifier string.
// The identifier is used to determine which module genesis information belongs
// to so it may be appropriately routed during init chain.
// Within this application default genesis information is retrieved from
// the ModuleBasicManager which populates json from each BasicModule
// object provided to it during init.
type GenesisState map[string]json.RawMessage

// NewDefaultGenesisState generates the default state for the application.
func NewDefaultGenesisState(cdc codec.JSONCodec) GenesisState {
	return ModuleBasics.DefaultGenesis(cdc)
}