R4R: Enable/disable withdraw addresses with a parameter

PENDING.md

@@ -27,8 +27,9 @@ BREAKING CHANGES
   * [\#3064](https://github.com/cosmos/cosmos-sdk/issues/3064) Sanitize `sdk.Coin` denom. Coins denoms are now case insensitive, i.e. 100fooToken equals to 100FOOTOKEN.
   * [\#3195](https://github.com/cosmos/cosmos-sdk/issues/3195) Allows custom configuration for syncable strategy
   * [\#3242](https://github.com/cosmos/cosmos-sdk/issues/3242) Fix infinite gas
-    meter utilization during aborted ante handler executions.
-  * [staking] \#2222 `/stake` -> `/staking` module rename
+  meter utilization during aborted ante handler executions.
+  * [\#2222] [x/staking] `/stake` -> `/staking` module rename
+  * \#3292 [x/distribution] Enable or disable withdraw addresses with a parameter in the param store
   * [staking] \#1402 Redelegation and unbonding-delegation structs changed to include multiple an array of entries 
 
 * Tendermint

cmd/gaia/cmd/gaiad/main.go

@@ -4,8 +4,6 @@ import (
 	"encoding/json"
 	"io"
 
-	"github.com/cosmos/cosmos-sdk/store"
-
 	"github.com/cosmos/cosmos-sdk/baseapp"
 	"github.com/cosmos/cosmos-sdk/store"
 

x/distribution/genesis.go

@@ -11,6 +11,7 @@ func InitGenesis(ctx sdk.Context, keeper Keeper, data types.GenesisState) {
 	keeper.SetCommunityTax(ctx, data.CommunityTax)
 	keeper.SetBaseProposerReward(ctx, data.BaseProposerReward)
 	keeper.SetBonusProposerReward(ctx, data.BonusProposerReward)
+	keeper.SetWithdrawAddrEnabled(ctx, data.WithdrawAddrEnabled)
 	for _, dwi := range data.DelegatorWithdrawInfos {
 		keeper.SetDelegatorWithdrawAddr(ctx, dwi.DelegatorAddr, dwi.WithdrawAddr)
 	}
@@ -39,6 +40,7 @@ func ExportGenesis(ctx sdk.Context, keeper Keeper) types.GenesisState {
 	communityTax := keeper.GetCommunityTax(ctx)
 	baseProposerRewards := keeper.GetBaseProposerReward(ctx)
 	bonusProposerRewards := keeper.GetBonusProposerReward(ctx)
+	withdrawAddrEnabled := keeper.GetWithdrawAddrEnabled(ctx)
 	dwi := make([]types.DelegatorWithdrawInfo, 0)
 	keeper.IterateDelegatorWithdrawAddrs(ctx, func(del sdk.AccAddress, addr sdk.AccAddress) (stop bool) {
 		dwi = append(dwi, types.DelegatorWithdrawInfo{
@@ -102,6 +104,6 @@ func ExportGenesis(ctx sdk.Context, keeper Keeper) types.GenesisState {
 			return false
 		},
 	)
-	return types.NewGenesisState(feePool, communityTax, baseProposerRewards, bonusProposerRewards, dwi, pp, outstanding,
-		acc, his, cur, dels, slashes)
+	return types.NewGenesisState(feePool, communityTax, baseProposerRewards, bonusProposerRewards, withdrawAddrEnabled,
+		dwi, pp, outstanding, acc, his, cur, dels, slashes)
 }

x/distribution/handler.go

@@ -27,7 +27,10 @@ func NewHandler(k keeper.Keeper) sdk.Handler {
 
 func handleMsgModifyWithdrawAddress(ctx sdk.Context, msg types.MsgSetWithdrawAddress, k keeper.Keeper) sdk.Result {
 
-	k.SetDelegatorWithdrawAddr(ctx, msg.DelegatorAddr, msg.WithdrawAddr)
+	err := k.SetWithdrawAddr(ctx, msg.DelegatorAddr, msg.WithdrawAddr)
+	if err != nil {
+		return err.Result()
+	}
 
 	tags := sdk.NewTags(
 		tags.Delegator, []byte(msg.DelegatorAddr.String()),

x/distribution/keeper/keeper.go

@@ -35,6 +35,17 @@ func NewKeeper(cdc *codec.Codec, key sdk.StoreKey, paramSpace params.Subspace, c
 	return keeper
 }
 
+// set withdraw address
+func (k Keeper) SetWithdrawAddr(ctx sdk.Context, delegatorAddr sdk.AccAddress, withdrawAddr sdk.AccAddress) sdk.Error {
+	if !k.GetWithdrawAddrEnabled(ctx) {
+		return types.ErrSetWithdrawAddrDisabled(k.codespace)
+	}
+
+	k.SetDelegatorWithdrawAddr(ctx, delegatorAddr, withdrawAddr)
+
+	return nil
+}
+
 // withdraw rewards from a delegation
 func (k Keeper) WithdrawDelegationRewards(ctx sdk.Context, delAddr sdk.AccAddress, valAddr sdk.ValAddress) sdk.Error {
 	val := k.stakingKeeper.Validator(ctx, valAddr)

x/distribution/keeper/keeper_test.go

@@ -9,6 +9,20 @@ import (
 	"github.com/cosmos/cosmos-sdk/x/distribution/types"
 )
 
+func TestSetWithdrawAddr(t *testing.T) {
+	ctx, _, keeper, _, _ := CreateTestInputDefault(t, false, 1000)
+
+	keeper.SetWithdrawAddrEnabled(ctx, false)
+
+	err := keeper.SetWithdrawAddr(ctx, delAddr1, delAddr2)
+	require.NotNil(t, err)
+
+	keeper.SetWithdrawAddrEnabled(ctx, true)
+
+	err = keeper.SetWithdrawAddr(ctx, delAddr1, delAddr2)
+	require.Nil(t, err)
+}
+
 func TestWithdrawValidatorCommission(t *testing.T) {
 	ctx, ak, keeper, _, _ := CreateTestInputDefault(t, false, 1000)
 

x/distribution/keeper/key.go

@@ -27,6 +27,7 @@ var (
 	ParamStoreKeyCommunityTax        = []byte("communitytax")
 	ParamStoreKeyBaseProposerReward  = []byte("baseproposerreward")
 	ParamStoreKeyBonusProposerReward = []byte("bonusproposerreward")
+	ParamStoreKeyWithdrawAddrEnabled = []byte("withdrawaddrenabled")
 )
 
 // gets an address from a delegator's withdraw info key

x/distribution/keeper/params.go

@@ -11,6 +11,7 @@ func ParamTypeTable() params.TypeTable {
 		ParamStoreKeyCommunityTax, sdk.Dec{},
 		ParamStoreKeyBaseProposerReward, sdk.Dec{},
 		ParamStoreKeyBonusProposerReward, sdk.Dec{},
+		ParamStoreKeyWithdrawAddrEnabled, false,
 	)
 }
 
@@ -52,3 +53,16 @@ func (k Keeper) GetBonusProposerReward(ctx sdk.Context) sdk.Dec {
 func (k Keeper) SetBonusProposerReward(ctx sdk.Context, percent sdk.Dec) {
 	k.paramSpace.Set(ctx, ParamStoreKeyBonusProposerReward, &percent)
 }
+
+// returns the current WithdrawAddrEnabled
+// nolint: errcheck
+func (k Keeper) GetWithdrawAddrEnabled(ctx sdk.Context) bool {
+	var enabled bool
+	k.paramSpace.Get(ctx, ParamStoreKeyWithdrawAddrEnabled, &enabled)
+	return enabled
+}
+
+// nolint: errcheck
+func (k Keeper) SetWithdrawAddrEnabled(ctx sdk.Context, enabled bool) {
+	k.paramSpace.Set(ctx, ParamStoreKeyWithdrawAddrEnabled, &enabled)
+}

x/distribution/types/errors.go

@@ -8,10 +8,11 @@ import (
 type CodeType = sdk.CodeType
 
 const (
-	DefaultCodespace          sdk.CodespaceType = "DISTR"
-	CodeInvalidInput          CodeType          = 103
-	CodeNoDistributionInfo    CodeType          = 104
-	CodeNoValidatorCommission CodeType          = 105
+	DefaultCodespace            sdk.CodespaceType = "DISTR"
+	CodeInvalidInput            CodeType          = 103
+	CodeNoDistributionInfo      CodeType          = 104
+	CodeNoValidatorCommission   CodeType          = 105
+	CodeSetWithdrawAddrDisabled CodeType          = 106
 )
 
 func ErrNilDelegatorAddr(codespace sdk.CodespaceType) sdk.Error {
@@ -32,3 +33,6 @@ func ErrNoValidatorDistInfo(codespace sdk.CodespaceType) sdk.Error {
 func ErrNoValidatorCommission(codespace sdk.CodespaceType) sdk.Error {
 	return sdk.NewError(codespace, CodeNoValidatorCommission, "no validator commission to withdraw")
 }
+func ErrSetWithdrawAddrDisabled(codespace sdk.CodespaceType) sdk.Error {
+	return sdk.NewError(codespace, CodeSetWithdrawAddrDisabled, "set withdraw address disabled")
+}

x/distribution/types/genesis.go

@@ -52,6 +52,7 @@ type GenesisState struct {
 	CommunityTax                    sdk.Dec                                `json:"community_tax"`
 	BaseProposerReward              sdk.Dec                                `json:"base_proposer_reward"`
 	BonusProposerReward             sdk.Dec                                `json:"bonus_proposer_reward"`
+	WithdrawAddrEnabled             bool                                   `json:"withdraw_addr_enabled"`
 	DelegatorWithdrawInfos          []DelegatorWithdrawInfo                `json:"delegator_withdraw_infos"`
 	PreviousProposer                sdk.ConsAddress                        `json:"previous_proposer"`
 	OutstandingRewards              sdk.DecCoins                           `json:"outstanding_rewards"`
@@ -63,7 +64,7 @@ type GenesisState struct {
 }
 
 func NewGenesisState(feePool FeePool, communityTax, baseProposerReward, bonusProposerReward sdk.Dec,
-	dwis []DelegatorWithdrawInfo, pp sdk.ConsAddress, r OutstandingRewards,
+	withdrawAddrEnabled bool, dwis []DelegatorWithdrawInfo, pp sdk.ConsAddress, r OutstandingRewards,
 	acc []ValidatorAccumulatedCommissionRecord, historical []ValidatorHistoricalRewardsRecord,
 	cur []ValidatorCurrentRewardsRecord, dels []DelegatorStartingInfoRecord,
 	slashes []ValidatorSlashEventRecord) GenesisState {
@@ -73,6 +74,7 @@ func NewGenesisState(feePool FeePool, communityTax, baseProposerReward, bonusPro
 		CommunityTax:                    communityTax,
 		BaseProposerReward:              baseProposerReward,
 		BonusProposerReward:             bonusProposerReward,
+		WithdrawAddrEnabled:             withdrawAddrEnabled,
 		DelegatorWithdrawInfos:          dwis,
 		PreviousProposer:                pp,
 		OutstandingRewards:              r,
@@ -91,6 +93,7 @@ func DefaultGenesisState() GenesisState {
 		CommunityTax:                    sdk.NewDecWithPrec(2, 2), // 2%
 		BaseProposerReward:              sdk.NewDecWithPrec(1, 2), // 1%
 		BonusProposerReward:             sdk.NewDecWithPrec(4, 2), // 4%
+		WithdrawAddrEnabled:             true,
 		DelegatorWithdrawInfos:          []DelegatorWithdrawInfo{},
 		PreviousProposer:                nil,
 		OutstandingRewards:              sdk.DecCoins{},