R4R: Add a flag to export for zero-height start

PENDING.md

@@ -33,7 +33,9 @@ FEATURES
   * [app] \#2791 Support export at a specific height, with `gaiad export --height=HEIGHT`.
   * [x/gov] [#2479](https://github.com/cosmos/cosmos-sdk/issues/2479) Implemented querier
   for getting governance parameters.
+  * [app] \#2663 - Runtime-assertable invariants
   * [app] \#2791 Support export at a specific height, with `gaiad export --height=HEIGHT`.
+  * [app] \#2812 Support export alterations to prepare for restarting at zero-height
 
 * SDK
     * [simulator] \#2682 MsgEditValidator now looks at the validator's max rate, thus it now succeeds a significant portion of the time

cmd/gaia/app/app.go

@@ -1,7 +1,6 @@
 package app
 
 import (
-	"encoding/json"
 	"fmt"
 	"io"
 	"os"
@@ -22,7 +21,6 @@ import (
 	cmn "github.com/tendermint/tendermint/libs/common"
 	dbm "github.com/tendermint/tendermint/libs/db"
 	"github.com/tendermint/tendermint/libs/log"
-	tmtypes "github.com/tendermint/tendermint/types"
 )
 
 const (
@@ -210,6 +208,8 @@ func (app *GaiaApp) EndBlocker(ctx sdk.Context, req abci.RequestEndBlock) abci.R
 	tags := gov.EndBlocker(ctx, app.govKeeper)
 	validatorUpdates := stake.EndBlocker(ctx, app.stakeKeeper)
 
+	app.assertRuntimeInvariants()
+
 	return abci.ResponseEndBlock{
 		ValidatorUpdates: validatorUpdates,
 		Tags:             tags,
@@ -290,40 +290,14 @@ func (app *GaiaApp) initChainer(ctx sdk.Context, req abci.RequestInitChain) abci
 		}
 	}
 
+	// assert runtime invariants
+	app.assertRuntimeInvariants()
+
 	return abci.ResponseInitChain{
 		Validators: validators,
 	}
 }
 
-// export the state of gaia for a genesis file
-func (app *GaiaApp) ExportAppStateAndValidators() (appState json.RawMessage, validators []tmtypes.GenesisValidator, err error) {
-	ctx := app.NewContext(true, abci.Header{})
-
-	// iterate to get the accounts
-	accounts := []GenesisAccount{}
-	appendAccount := func(acc auth.Account) (stop bool) {
-		account := NewGenesisAccountI(acc)
-		accounts = append(accounts, account)
-		return false
-	}
-	app.accountKeeper.IterateAccounts(ctx, appendAccount)
-	genState := NewGenesisState(
-		accounts,
-		auth.ExportGenesis(ctx, app.feeCollectionKeeper),
-		stake.ExportGenesis(ctx, app.stakeKeeper),
-		mint.ExportGenesis(ctx, app.mintKeeper),
-		distr.ExportGenesis(ctx, app.distrKeeper),
-		gov.ExportGenesis(ctx, app.govKeeper),
-		slashing.ExportGenesis(ctx, app.slashingKeeper),
-	)
-	appState, err = codec.MarshalJSONIndent(app.cdc, genState)
-	if err != nil {
-		return nil, nil, err
-	}
-	validators = stake.WriteValidators(ctx, app.stakeKeeper)
-	return appState, validators, nil
-}
-
 // load a particular height
 func (app *GaiaApp) LoadHeight(height int64) error {
 	return app.LoadVersion(height, app.keyMain)

cmd/gaia/app/app_test.go

@@ -49,6 +49,6 @@ func TestGaiadExport(t *testing.T) {
 
 	// Making a new app object with the db, so that initchain hasn't been called
 	newGapp := NewGaiaApp(log.NewTMLogger(log.NewSyncWriter(os.Stdout)), db, nil)
-	_, _, err := newGapp.ExportAppStateAndValidators()
+	_, _, err := newGapp.ExportAppStateAndValidators(false)
 	require.NoError(t, err, "ExportAppStateAndValidators should not have an error")
 }

cmd/gaia/app/export.go

@@ -0,0 +1,111 @@
+package app
+
+import (
+	"encoding/json"
+
+	"github.com/cosmos/cosmos-sdk/codec"
+	sdk "github.com/cosmos/cosmos-sdk/types"
+	"github.com/cosmos/cosmos-sdk/x/auth"
+	distr "github.com/cosmos/cosmos-sdk/x/distribution"
+	"github.com/cosmos/cosmos-sdk/x/gov"
+	"github.com/cosmos/cosmos-sdk/x/mint"
+	"github.com/cosmos/cosmos-sdk/x/slashing"
+	stake "github.com/cosmos/cosmos-sdk/x/stake"
+	abci "github.com/tendermint/tendermint/abci/types"
+	tmtypes "github.com/tendermint/tendermint/types"
+)
+
+// export the state of gaia for a genesis file
+func (app *GaiaApp) ExportAppStateAndValidators(forZeroHeight bool) (appState json.RawMessage, validators []tmtypes.GenesisValidator, err error) {
+	ctx := app.NewContext(true, abci.Header{Height: app.LastBlockHeight()})
+
+	// prepare for fresh start at zero height
+	if forZeroHeight {
+
+		/* Handle fee distribution state. */
+
+		// withdraw all delegator & validator rewards
+		app.accountKeeper.IterateAccounts(ctx, func(acc auth.Account) (stop bool) {
+			app.distrKeeper.WithdrawDelegationRewardsAll(ctx, acc.GetAddress())
+			_ = app.distrKeeper.WithdrawValidatorRewardsAll(ctx, sdk.ValAddress(acc.GetAddress()))
+			return false
+		})
+
+		// delete all distribution infos
+		app.distrKeeper.RemoveValidatorDistInfos(ctx)
+		app.distrKeeper.RemoveDelegationDistInfos(ctx)
+
+		// assert that the fee pool is empty
+		feePool := app.distrKeeper.GetFeePool(ctx)
+		if !feePool.TotalValAccum.Accum.IsZero() {
+			panic("unexpected leftover validator accum")
+		}
+		bondDenom := app.stakeKeeper.GetParams(ctx).BondDenom
+		if !feePool.ValPool.AmountOf(bondDenom).IsZero() {
+			panic("unexpected leftover validator pool coins")
+		}
+
+		// reset fee pool height, save fee pool
+		feePool.TotalValAccum.UpdateHeight = 0
+		app.distrKeeper.SetFeePool(ctx, feePool)
+
+		/* Handle stake state. */
+
+		// iterate through validators by power descending, reset bond height, update bond intra-tx counter
+		store := ctx.KVStore(app.keyStake)
+		iter := sdk.KVStoreReversePrefixIterator(store, stake.ValidatorsByPowerIndexKey)
+		counter := int16(0)
+		for ; iter.Valid(); iter.Next() {
+			addr := sdk.ValAddress(iter.Value())
+			validator, found := app.stakeKeeper.GetValidator(ctx, addr)
+			if !found {
+				panic("expected validator, not found")
+			}
+			validator.BondHeight = 0
+			validator.BondIntraTxCounter = counter
+			// AFAICT we do not need to reset unbonding height since it is not used.
+			app.stakeKeeper.SetValidator(ctx, validator)
+			counter++
+		}
+
+		// AFAICT we do not need to reset bond heights since they are unused.
+
+		/* Handle slashing state. */
+
+		// we have to clear the slashing periods, since they reference heights
+		app.slashingKeeper.DeleteValidatorSlashingPeriods(ctx)
+
+		// reset start height on signing infos
+		app.slashingKeeper.IterateValidatorSigningInfos(ctx, func(addr sdk.ConsAddress, info slashing.ValidatorSigningInfo) (stop bool) {
+			info.StartHeight = 0
+			app.slashingKeeper.SetValidatorSigningInfo(ctx, addr, info)
+			return false
+		})
+
+	}
+
+	// iterate to get the accounts
+	accounts := []GenesisAccount{}
+	appendAccount := func(acc auth.Account) (stop bool) {
+		account := NewGenesisAccountI(acc)
+		accounts = append(accounts, account)
+		return false
+	}
+	app.accountKeeper.IterateAccounts(ctx, appendAccount)
+
+	genState := NewGenesisState(
+		accounts,
+		auth.ExportGenesis(ctx, app.feeCollectionKeeper),
+		stake.ExportGenesis(ctx, app.stakeKeeper),
+		mint.ExportGenesis(ctx, app.mintKeeper),
+		distr.ExportGenesis(ctx, app.distrKeeper),
+		gov.ExportGenesis(ctx, app.govKeeper),
+		slashing.ExportGenesis(ctx, app.slashingKeeper),
+	)
+	appState, err = codec.MarshalJSONIndent(app.cdc, genState)
+	if err != nil {
+		return nil, nil, err
+	}
+	validators = stake.WriteValidators(ctx, app.stakeKeeper)
+	return appState, validators, nil
+}

cmd/gaia/app/genesis.go

@@ -287,7 +287,7 @@ func CollectStdTxs(cdc *codec.Codec, moniker string, genTxsDir string, genDoc tm
 
 func NewDefaultGenesisAccount(addr sdk.AccAddress) GenesisAccount {
 	accAuth := auth.NewBaseAccountWithAddress(addr)
-	coins :=sdk.Coins{
+	coins := sdk.Coins{
 		{"fooToken", sdk.NewInt(1000)},
 		{bondDenom, freeFermionsAcc},
 	}

cmd/gaia/app/invariants.go

@@ -0,0 +1,34 @@
+package app
+
+import (
+	"fmt"
+	"time"
+
+	banksim "github.com/cosmos/cosmos-sdk/x/bank/simulation"
+	distrsim "github.com/cosmos/cosmos-sdk/x/distribution/simulation"
+	"github.com/cosmos/cosmos-sdk/x/mock/simulation"
+	stakesim "github.com/cosmos/cosmos-sdk/x/stake/simulation"
+)
+
+func (app *GaiaApp) runtimeInvariants() []simulation.Invariant {
+	return []simulation.Invariant{
+		banksim.NonnegativeBalanceInvariant(app.accountKeeper),
+		distrsim.ValAccumInvariants(app.distrKeeper, app.stakeKeeper),
+		stakesim.SupplyInvariants(app.bankKeeper, app.stakeKeeper,
+			app.feeCollectionKeeper, app.distrKeeper, app.accountKeeper),
+		stakesim.PositivePowerInvariant(app.stakeKeeper),
+	}
+}
+
+func (app *GaiaApp) assertRuntimeInvariants() {
+	invariants := app.runtimeInvariants()
+	start := time.Now()
+	for _, inv := range invariants {
+		if err := inv(app.BaseApp); err != nil {
+			panic(fmt.Errorf("invariant broken: %s", err))
+		}
+	}
+	end := time.Now()
+	diff := end.Sub(start)
+	app.BaseApp.Logger.With("module", "invariants").Info("Asserted all invariants", "duration", diff)
+}

cmd/gaia/app/sim_test.go

@@ -311,7 +311,7 @@ func TestGaiaImportExport(t *testing.T) {
 
 	fmt.Printf("Exporting genesis...\n")
 
-	appState, _, err := app.ExportAppStateAndValidators()
+	appState, _, err := app.ExportAppStateAndValidators(false)
 	if err != nil {
 		panic(err)
 	}

cmd/gaia/cmd/gaiad/main.go

@@ -64,7 +64,7 @@ func newApp(logger log.Logger, db dbm.DB, traceStore io.Writer) abci.Application
 }
 
 func exportAppStateAndTMValidators(
-	logger log.Logger, db dbm.DB, traceStore io.Writer, height int64,
+	logger log.Logger, db dbm.DB, traceStore io.Writer, height int64, forZeroHeight bool,
 ) (json.RawMessage, []tmtypes.GenesisValidator, error) {
 	gApp := app.NewGaiaApp(logger, db, traceStore)
 	if height != -1 {
@@ -73,5 +73,5 @@ func exportAppStateAndTMValidators(
 			return nil, nil, err
 		}
 	}
-	return gApp.ExportAppStateAndValidators()
+	return gApp.ExportAppStateAndValidators(forZeroHeight)
 }

docs/examples/basecoin/cmd/basecoind/main.go

@@ -126,7 +126,7 @@ func newApp(logger log.Logger, db dbm.DB, storeTracer io.Writer) abci.Applicatio
 	return app.NewBasecoinApp(logger, db, baseapp.SetPruning(viper.GetString("pruning")))
 }
 
-func exportAppStateAndTMValidators(logger log.Logger, db dbm.DB, storeTracer io.Writer, _ int64) (
+func exportAppStateAndTMValidators(logger log.Logger, db dbm.DB, storeTracer io.Writer, _ int64, _ bool) (
 	json.RawMessage, []tmtypes.GenesisValidator, error) {
 	bapp := app.NewBasecoinApp(logger, db)
 	return bapp.ExportAppStateAndValidators()

docs/examples/democoin/cmd/democoind/main.go

@@ -133,7 +133,7 @@ func newApp(logger log.Logger, db dbm.DB, _ io.Writer) abci.Application {
 	return app.NewDemocoinApp(logger, db)
 }
 
-func exportAppStateAndTMValidators(logger log.Logger, db dbm.DB, _ io.Writer, _ int64) (
+func exportAppStateAndTMValidators(logger log.Logger, db dbm.DB, _ io.Writer, _ int64, _ bool) (
 	json.RawMessage, []tmtypes.GenesisValidator, error) {
 	dapp := app.NewDemocoinApp(logger, db)
 	return dapp.ExportAppStateAndValidators()

docs/gaia/join-testnet.md

@@ -142,7 +142,13 @@ gaiad export > [filename].json
 You can also export state from a particular height (at the end of processing the block of that height):
 
 ```bash
-gaiad export --height=[height] > [filename].json
+gaiad export --height [height] > [filename].json
+```
+
+If you plan to start a new network from the exported state, export with the `--for-zero-height` flag:
+
+```bash
+gaiad export --height [height] --for-zero-height > [filename].json
 ```
 
 ## Upgrade to Validator Node

server/constructors.go

@@ -19,7 +19,7 @@ type (
 
 	// AppExporter is a function that dumps all app state to
 	// JSON-serializable structure and returns the current validator set.
-	AppExporter func(log.Logger, dbm.DB, io.Writer, int64) (json.RawMessage, []tmtypes.GenesisValidator, error)
+	AppExporter func(log.Logger, dbm.DB, io.Writer, int64, bool) (json.RawMessage, []tmtypes.GenesisValidator, error)
 )
 
 func openDB(rootDir string) (dbm.DB, error) {

server/export.go

@@ -14,7 +14,8 @@ import (
 )
 
 const (
-	flagHeight = "height"
+	flagHeight        = "height"
+	flagForZeroHeight = "for-zero-height"
 )
 
 // ExportCmd dumps app state to JSON.
@@ -50,7 +51,8 @@ func ExportCmd(ctx *Context, cdc *codec.Codec, appExporter AppExporter) *cobra.C
 				return err
 			}
 			height := viper.GetInt64(flagHeight)
-			appState, validators, err := appExporter(ctx.Logger, db, traceWriter, height)
+			forZeroHeight := viper.GetBool(flagForZeroHeight)
+			appState, validators, err := appExporter(ctx.Logger, db, traceWriter, height, forZeroHeight)
 			if err != nil {
 				return errors.Errorf("error exporting state: %v\n", err)
 			}
@@ -73,6 +75,7 @@ func ExportCmd(ctx *Context, cdc *codec.Codec, appExporter AppExporter) *cobra.C
 		},
 	}
 	cmd.Flags().Int64(flagHeight, -1, "Export state from a particular height (-1 means latest height)")
+	cmd.Flags().Bool(flagForZeroHeight, false, "Export state to start at height zero (perform preproccessing)")
 	return cmd
 }
 

x/auth/client/txbuilder/txbuilder_test.go

@@ -9,8 +9,8 @@ import (
 	"github.com/cosmos/cosmos-sdk/codec"
 	sdk "github.com/cosmos/cosmos-sdk/types"
 	"github.com/cosmos/cosmos-sdk/x/auth"
-	"github.com/tendermint/tendermint/crypto/ed25519"
 	stakeTypes "github.com/cosmos/cosmos-sdk/x/stake/types"
+	"github.com/tendermint/tendermint/crypto/ed25519"
 )
 
 var (

x/distribution/keeper/delegation.go

@@ -42,6 +42,16 @@ func (k Keeper) RemoveDelegationDistInfo(ctx sdk.Context, delAddr sdk.AccAddress
 	store.Delete(GetDelegationDistInfoKey(delAddr, valOperatorAddr))
 }
 
+// remove all delegation distribution infos
+func (k Keeper) RemoveDelegationDistInfos(ctx sdk.Context) {
+	store := ctx.KVStore(k.storeKey)
+	iter := sdk.KVStorePrefixIterator(store, DelegationDistInfoKey)
+	defer iter.Close()
+	for ; iter.Valid(); iter.Next() {
+		store.Delete(iter.Key())
+	}
+}
+
 //___________________________________________________________________________________________
 
 // get the delegator withdraw address, return the delegator address if not set

x/distribution/keeper/validator.go

@@ -40,6 +40,16 @@ func (k Keeper) RemoveValidatorDistInfo(ctx sdk.Context, valAddr sdk.ValAddress)
 	store.Delete(GetValidatorDistInfoKey(valAddr))
 }
 
+// remove all validator distribution infos
+func (k Keeper) RemoveValidatorDistInfos(ctx sdk.Context) {
+	store := ctx.KVStore(k.storeKey)
+	iter := sdk.KVStorePrefixIterator(store, ValidatorDistInfoKey)
+	defer iter.Close()
+	for ; iter.Valid(); iter.Next() {
+		store.Delete(iter.Key())
+	}
+}
+
 // Get the calculated accum of a validator at the current block
 // without affecting the state.
 func (k Keeper) GetValidatorAccum(ctx sdk.Context, operatorAddr sdk.ValAddress) (sdk.Dec, sdk.Error) {