Add module invariants and input validations (#14)

Reviewed-on: deep-stack/laconic2d#14
Co-authored-by: Prathamesh Musale <prathamesh.musale0@gmail.com>
Co-committed-by: Prathamesh Musale <prathamesh.musale0@gmail.com>

x/auction/keeper/invariants.go

@@ -0,0 +1,37 @@
+package keeper
+
+import (
+	"fmt"
+
+	sdk "github.com/cosmos/cosmos-sdk/types"
+
+	types "git.vdb.to/cerc-io/laconic2d/x/auction"
+)
+
+// RegisterInvariants registers all auction invariants
+func RegisterInvariants(ir sdk.InvariantRegistry, k *Keeper) {
+	ir.RegisterRoute(types.ModuleName, "module-account", ModuleAccountInvariant(k))
+}
+
+// AllInvariants runs all invariants of the auction module.
+func AllInvariants(k *Keeper) sdk.Invariant {
+	return func(ctx sdk.Context) (string, bool) {
+		return ModuleAccountInvariant(k)(ctx)
+	}
+}
+
+// ModuleAccountInvariant checks that the 'auction' module account balance is non-negative.
+func ModuleAccountInvariant(k *Keeper) sdk.Invariant {
+	return func(ctx sdk.Context) (string, bool) {
+		moduleAddress := k.accountKeeper.GetModuleAddress(types.ModuleName)
+		if k.bankKeeper.GetAllBalances(ctx, moduleAddress).IsAnyNegative() {
+			return sdk.FormatInvariant(
+				types.ModuleName,
+				"module-account",
+				fmt.Sprintf("Module account '%s' has negative balance.", types.ModuleName),
+			), true
+		}
+
+		return "", false
+	}
+}

x/auction/keeper/keeper.go

@@ -285,12 +285,11 @@ func (k Keeper) QueryAuctionsByBidder(ctx sdk.Context, bidderAddress string) ([]
 
 // CreateAuction creates a new auction.
 func (k Keeper) CreateAuction(ctx sdk.Context, msg auctiontypes.MsgCreateAuction) (*auctiontypes.Auction, error) {
-	// TODO: Setup checks
 	// Might be called from another module directly, always validate.
-	// err := msg.ValidateBasic()
-	// if err != nil {
-	// 	return nil, err
-	// }
+	err := msg.ValidateBasic()
+	if err != nil {
+		return nil, err
+	}
 
 	signerAddress, err := sdk.AccAddressFromBech32(msg.Signer)
 	if err != nil {

x/auction/keeper/msg_server.go

@@ -52,6 +52,10 @@ func (ms msgServer) CreateAuction(c context.Context, msg *auctiontypes.MsgCreate
 // CommitBid is the command for committing a bid
 // nolint: all
 func (ms msgServer) CommitBid(c context.Context, msg *auctiontypes.MsgCommitBid) (*auctiontypes.MsgCommitBidResponse, error) {
+	if err := msg.ValidateBasic(); err != nil {
+		return nil, err
+	}
+
 	ctx := sdk.UnwrapSDKContext(c)
 
 	signerAddress, err := sdk.AccAddressFromBech32(msg.Signer)
@@ -83,6 +87,10 @@ func (ms msgServer) CommitBid(c context.Context, msg *auctiontypes.MsgCommitBid)
 // RevealBid is the command for revealing a bid
 // nolint: all
 func (ms msgServer) RevealBid(c context.Context, msg *auctiontypes.MsgRevealBid) (*auctiontypes.MsgRevealBidResponse, error) {
+	if err := msg.ValidateBasic(); err != nil {
+		return nil, err
+	}
+
 	ctx := sdk.UnwrapSDKContext(c)
 
 	signerAddress, err := sdk.AccAddressFromBech32(msg.Signer)

x/auction/module/module.go

@@ -27,6 +27,7 @@ var (
 	_ module.HasServices         = AppModule{}
 	_ module.HasConsensusVersion = AppModule{}
 	_ appmodule.HasEndBlocker    = AppModule{}
+	_ module.HasInvariants       = AppModule{}
 )
 
 // ConsensusVersion defines the current module consensus version
@@ -126,6 +127,12 @@ func (am AppModule) EndBlock(ctx context.Context) error {
 	return EndBlocker(ctx, am.keeper)
 }
 
+// module.HasInvariants
+
+func (am AppModule) RegisterInvariants(ir sdk.InvariantRegistry) {
+	keeper.RegisterInvariants(ir, am.keeper)
+}
+
 // Get the root tx command of this module
 func (AppModule) GetTxCmd() *cobra.Command {
 	return cli.GetTxCmd()

x/bond/keeper/invariants.go

@@ -0,0 +1,37 @@
+package keeper
+
+import (
+	"fmt"
+
+	sdk "github.com/cosmos/cosmos-sdk/types"
+
+	types "git.vdb.to/cerc-io/laconic2d/x/bond"
+)
+
+// RegisterInvariants registers all bond invariants
+func RegisterInvariants(ir sdk.InvariantRegistry, k *Keeper) {
+	ir.RegisterRoute(types.ModuleName, "module-account", ModuleAccountInvariant(k))
+}
+
+// AllInvariants runs all invariants of the bond module.
+func AllInvariants(k *Keeper) sdk.Invariant {
+	return func(ctx sdk.Context) (string, bool) {
+		return ModuleAccountInvariant(k)(ctx)
+	}
+}
+
+// ModuleAccountInvariant checks that the 'bond' module account balance is non-negative.
+func ModuleAccountInvariant(k *Keeper) sdk.Invariant {
+	return func(ctx sdk.Context) (string, bool) {
+		moduleAddress := k.accountKeeper.GetModuleAddress(types.ModuleName)
+		if k.bankKeeper.GetAllBalances(ctx, moduleAddress).IsAnyNegative() {
+			return sdk.FormatInvariant(
+				types.ModuleName,
+				"module-account",
+				fmt.Sprintf("Module account '%s' has negative balance.", types.ModuleName),
+			), true
+		}
+
+		return "", false
+	}
+}

x/bond/keeper/msg_server.go

@@ -20,6 +20,10 @@ func NewMsgServerImpl(keeper *Keeper) bond.MsgServer {
 }
 
 func (ms msgServer) CreateBond(c context.Context, msg *bond.MsgCreateBond) (*bond.MsgCreateBondResponse, error) {
+	if err := msg.ValidateBasic(); err != nil {
+		return nil, err
+	}
+
 	ctx := sdk.UnwrapSDKContext(c)
 
 	signerAddress, err := sdk.AccAddressFromBech32(msg.Signer)
@@ -50,6 +54,10 @@ func (ms msgServer) CreateBond(c context.Context, msg *bond.MsgCreateBond) (*bon
 
 // RefillBond implements bond.MsgServer.
 func (ms msgServer) RefillBond(c context.Context, msg *bond.MsgRefillBond) (*bond.MsgRefillBondResponse, error) {
+	if err := msg.ValidateBasic(); err != nil {
+		return nil, err
+	}
+
 	ctx := sdk.UnwrapSDKContext(c)
 
 	signerAddress, err := sdk.AccAddressFromBech32(msg.Signer)
@@ -81,6 +89,10 @@ func (ms msgServer) RefillBond(c context.Context, msg *bond.MsgRefillBond) (*bon
 
 // WithdrawBond implements bond.MsgServer.
 func (ms msgServer) WithdrawBond(c context.Context, msg *bond.MsgWithdrawBond) (*bond.MsgWithdrawBondResponse, error) {
+	if err := msg.ValidateBasic(); err != nil {
+		return nil, err
+	}
+
 	ctx := sdk.UnwrapSDKContext(c)
 
 	signerAddress, err := sdk.AccAddressFromBech32(msg.Signer)
@@ -112,11 +124,17 @@ func (ms msgServer) WithdrawBond(c context.Context, msg *bond.MsgWithdrawBond) (
 
 // CancelBond implements bond.MsgServer.
 func (ms msgServer) CancelBond(c context.Context, msg *bond.MsgCancelBond) (*bond.MsgCancelBondResponse, error) {
+	if err := msg.ValidateBasic(); err != nil {
+		return nil, err
+	}
+
 	ctx := sdk.UnwrapSDKContext(c)
+
 	signerAddress, err := sdk.AccAddressFromBech32(msg.Signer)
 	if err != nil {
 		return nil, err
 	}
+
 	_, err = ms.k.CancelBond(ctx, msg.Id, signerAddress)
 	if err != nil {
 		return nil, err

x/bond/module/module.go

@@ -24,6 +24,7 @@ var (
 	_ module.HasGenesis          = AppModule{}
 	_ module.HasServices         = AppModule{}
 	_ module.HasConsensusVersion = AppModule{}
+	_ module.HasInvariants       = AppModule{}
 )
 
 // ConsensusVersion defines the current module consensus version
@@ -116,3 +117,9 @@ func (am AppModule) RegisterServices(cfg module.Configurator) {
 	bond.RegisterMsgServer(cfg.MsgServer(), keeper.NewMsgServerImpl(am.keeper))
 	bond.RegisterQueryServer(cfg.QueryServer(), keeper.NewQueryServerImpl(am.keeper))
 }
+
+// module.HasInvariants
+
+func (am AppModule) RegisterInvariants(ir sdk.InvariantRegistry) {
+	keeper.RegisterInvariants(ir, am.keeper)
+}

x/bond/msgs.go

@@ -1,7 +1,9 @@
 package bond
 
 import (
+	errorsmod "cosmossdk.io/errors"
 	sdk "github.com/cosmos/cosmos-sdk/types"
+	sdkerrors "github.com/cosmos/cosmos-sdk/types/errors"
 )
 
 var (
@@ -15,3 +17,49 @@ func NewMsgCreateBond(coins sdk.Coins, signer sdk.AccAddress) MsgCreateBond {
 		Signer: signer.String(),
 	}
 }
+
+func (msg MsgCreateBond) ValidateBasic() error {
+	if len(msg.Signer) == 0 {
+		return errorsmod.Wrap(sdkerrors.ErrInvalidAddress, msg.Signer)
+	}
+	if len(msg.Coins) == 0 || !msg.Coins.IsValid() {
+		return errorsmod.Wrap(sdkerrors.ErrInvalidCoins, "Invalid amount.")
+	}
+	return nil
+}
+
+func (msg MsgRefillBond) ValidateBasic() error {
+	if len(msg.Id) == 0 {
+		return errorsmod.Wrap(sdkerrors.ErrInvalidRequest, msg.Id)
+	}
+	if len(msg.Signer) == 0 {
+		return errorsmod.Wrap(sdkerrors.ErrInvalidAddress, msg.Signer)
+	}
+	if len(msg.Coins) == 0 || !msg.Coins.IsValid() {
+		return errorsmod.Wrap(sdkerrors.ErrInvalidCoins, "Invalid amount.")
+	}
+	return nil
+}
+
+func (msg MsgWithdrawBond) ValidateBasic() error {
+	if len(msg.Id) == 0 {
+		return errorsmod.Wrap(sdkerrors.ErrInvalidRequest, msg.Id)
+	}
+	if len(msg.Signer) == 0 {
+		return errorsmod.Wrap(sdkerrors.ErrInvalidAddress, msg.Signer)
+	}
+	if len(msg.Coins) == 0 || !msg.Coins.IsValid() {
+		return errorsmod.Wrap(sdkerrors.ErrInvalidCoins, "Invalid amount.")
+	}
+	return nil
+}
+
+func (msg MsgCancelBond) ValidateBasic() error {
+	if len(msg.Id) == 0 {
+		return errorsmod.Wrap(sdkerrors.ErrInvalidRequest, msg.Id)
+	}
+	if len(msg.Signer) == 0 {
+		return errorsmod.Wrap(sdkerrors.ErrInvalidAddress, msg.Signer)
+	}
+	return nil
+}

x/registry/keeper/invariants.go

@@ -0,0 +1,75 @@
+package keeper
+
+import (
+	"errors"
+	"fmt"
+
+	sdk "github.com/cosmos/cosmos-sdk/types"
+
+	types "git.vdb.to/cerc-io/laconic2d/x/registry"
+)
+
+// RegisterInvariants registers all registry invariants
+func RegisterInvariants(ir sdk.InvariantRegistry, k Keeper) {
+	ir.RegisterRoute(types.ModuleName, "module-account", ModuleAccountInvariant(&k))
+	ir.RegisterRoute(types.ModuleName, "record-bond", RecordBondInvariant(&k))
+}
+
+// AllInvariants runs all invariants of the registry module.
+func AllInvariants(k *Keeper) sdk.Invariant {
+	return func(ctx sdk.Context) (string, bool) {
+		res, stop := ModuleAccountInvariant(k)(ctx)
+		if stop {
+			return res, stop
+		}
+
+		return RecordBondInvariant(k)(ctx)
+	}
+}
+
+// ModuleAccountInvariant checks that the 'registry' module account balance is non-negative.
+func ModuleAccountInvariant(k *Keeper) sdk.Invariant {
+	return func(ctx sdk.Context) (string, bool) {
+		moduleAddress := k.accountKeeper.GetModuleAddress(types.ModuleName)
+		if k.bankKeeper.GetAllBalances(ctx, moduleAddress).IsAnyNegative() {
+			return sdk.FormatInvariant(
+				types.ModuleName,
+				"module-account",
+				fmt.Sprintf("Module account '%s' has negative balance.", types.ModuleName),
+			), true
+		}
+
+		return "", false
+	}
+}
+
+// RecordBondInvariant checks that for every record:
+// if bondId is not null, associated bond exists
+func RecordBondInvariant(k *Keeper) sdk.Invariant {
+	return func(ctx sdk.Context) (string, bool) {
+		err := k.Records.Walk(ctx, nil, func(key string, record types.Record) (bool, error) {
+			if record.BondId != "" {
+				bondExists, err := k.bondKeeper.HasBond(ctx, record.BondId)
+				if err != nil {
+					return true, err
+				}
+
+				if !bondExists {
+					return true, errors.New(record.Id)
+				}
+			}
+
+			return false, nil
+		})
+
+		if err != nil {
+			return sdk.FormatInvariant(
+				types.ModuleName,
+				"record-bond",
+				fmt.Sprintf("Bond not found for record id: '%s'.", err.Error()),
+			), true
+		}
+
+		return "", false
+	}
+}

x/registry/keeper/msg_server.go

@@ -20,6 +20,10 @@ func NewMsgServerImpl(keeper Keeper) registrytypes.MsgServer {
 }
 
 func (ms msgServer) SetRecord(c context.Context, msg *registrytypes.MsgSetRecord) (*registrytypes.MsgSetRecordResponse, error) {
+	if err := msg.ValidateBasic(); err != nil {
+		return nil, err
+	}
+
 	ctx := sdk.UnwrapSDKContext(c)
 
 	_, err := sdk.AccAddressFromBech32(msg.Signer)
@@ -51,6 +55,10 @@ func (ms msgServer) SetRecord(c context.Context, msg *registrytypes.MsgSetRecord
 
 // nolint: all
 func (ms msgServer) SetName(c context.Context, msg *registrytypes.MsgSetName) (*registrytypes.MsgSetNameResponse, error) {
+	if err := msg.ValidateBasic(); err != nil {
+		return nil, err
+	}
+
 	ctx := sdk.UnwrapSDKContext(c)
 
 	_, err := sdk.AccAddressFromBech32(msg.Signer)
@@ -80,6 +88,10 @@ func (ms msgServer) SetName(c context.Context, msg *registrytypes.MsgSetName) (*
 }
 
 func (ms msgServer) ReserveName(c context.Context, msg *registrytypes.MsgReserveAuthority) (*registrytypes.MsgReserveAuthorityResponse, error) {
+	if err := msg.ValidateBasic(); err != nil {
+		return nil, err
+	}
+
 	ctx := sdk.UnwrapSDKContext(c)
 
 	_, err := sdk.AccAddressFromBech32(msg.Signer)
@@ -114,6 +126,10 @@ func (ms msgServer) ReserveName(c context.Context, msg *registrytypes.MsgReserve
 
 // nolint: all
 func (ms msgServer) SetAuthorityBond(c context.Context, msg *registrytypes.MsgSetAuthorityBond) (*registrytypes.MsgSetAuthorityBondResponse, error) {
+	if err := msg.ValidateBasic(); err != nil {
+		return nil, err
+	}
+
 	ctx := sdk.UnwrapSDKContext(c)
 
 	_, err := sdk.AccAddressFromBech32(msg.Signer)
@@ -144,6 +160,10 @@ func (ms msgServer) SetAuthorityBond(c context.Context, msg *registrytypes.MsgSe
 }
 
 func (ms msgServer) DeleteName(c context.Context, msg *registrytypes.MsgDeleteNameAuthority) (*registrytypes.MsgDeleteNameAuthorityResponse, error) {
+	if err := msg.ValidateBasic(); err != nil {
+		return nil, err
+	}
+
 	ctx := sdk.UnwrapSDKContext(c)
 
 	_, err := sdk.AccAddressFromBech32(msg.Signer)
@@ -172,6 +192,10 @@ func (ms msgServer) DeleteName(c context.Context, msg *registrytypes.MsgDeleteNa
 }
 
 func (ms msgServer) RenewRecord(c context.Context, msg *registrytypes.MsgRenewRecord) (*registrytypes.MsgRenewRecordResponse, error) {
+	if err := msg.ValidateBasic(); err != nil {
+		return nil, err
+	}
+
 	ctx := sdk.UnwrapSDKContext(c)
 
 	_, err := sdk.AccAddressFromBech32(msg.Signer)
@@ -201,6 +225,10 @@ func (ms msgServer) RenewRecord(c context.Context, msg *registrytypes.MsgRenewRe
 
 // nolint: all
 func (ms msgServer) AssociateBond(c context.Context, msg *registrytypes.MsgAssociateBond) (*registrytypes.MsgAssociateBondResponse, error) {
+	if err := msg.ValidateBasic(); err != nil {
+		return nil, err
+	}
+
 	ctx := sdk.UnwrapSDKContext(c)
 
 	_, err := sdk.AccAddressFromBech32(msg.Signer)
@@ -231,6 +259,10 @@ func (ms msgServer) AssociateBond(c context.Context, msg *registrytypes.MsgAssoc
 }
 
 func (ms msgServer) DissociateBond(c context.Context, msg *registrytypes.MsgDissociateBond) (*registrytypes.MsgDissociateBondResponse, error) {
+	if err := msg.ValidateBasic(); err != nil {
+		return nil, err
+	}
+
 	ctx := sdk.UnwrapSDKContext(c)
 
 	_, err := sdk.AccAddressFromBech32(msg.Signer)
@@ -260,6 +292,10 @@ func (ms msgServer) DissociateBond(c context.Context, msg *registrytypes.MsgDiss
 }
 
 func (ms msgServer) DissociateRecords(c context.Context, msg *registrytypes.MsgDissociateRecords) (*registrytypes.MsgDissociateRecordsResponse, error) {
+	if err := msg.ValidateBasic(); err != nil {
+		return nil, err
+	}
+
 	ctx := sdk.UnwrapSDKContext(c)
 
 	_, err := sdk.AccAddressFromBech32(msg.Signer)
@@ -289,6 +325,10 @@ func (ms msgServer) DissociateRecords(c context.Context, msg *registrytypes.MsgD
 }
 
 func (ms msgServer) ReassociateRecords(c context.Context, msg *registrytypes.MsgReassociateRecords) (*registrytypes.MsgReassociateRecordsResponse, error) { //nolint: all
+	if err := msg.ValidateBasic(); err != nil {
+		return nil, err
+	}
+
 	ctx := sdk.UnwrapSDKContext(c)
 
 	_, err := sdk.AccAddressFromBech32(msg.Signer)

x/registry/module/module.go

@@ -27,6 +27,7 @@ var (
 	_ module.HasServices         = AppModule{}
 	_ module.HasConsensusVersion = AppModule{}
 	_ appmodule.HasEndBlocker    = AppModule{}
+	_ module.HasInvariants       = AppModule{}
 )
 
 // ConsensusVersion defines the current module consensus version.
@@ -127,6 +128,12 @@ func (am AppModule) EndBlock(ctx context.Context) error {
 	return EndBlocker(ctx, am.keeper)
 }
 
+// module.HasInvariants
+
+func (am AppModule) RegisterInvariants(ir sdk.InvariantRegistry) {
+	keeper.RegisterInvariants(ir, am.keeper)
+}
+
 // Get the root tx command of this module
 func (AppModule) GetTxCmd() *cobra.Command {
 	return cli.GetTxCmd()

x/registry/msgs.go

@@ -1,6 +1,8 @@
 package registry
 
 import (
+	"net/url"
+
 	errorsmod "cosmossdk.io/errors"
 	sdk "github.com/cosmos/cosmos-sdk/types"
 	sdkerrors "github.com/cosmos/cosmos-sdk/types/errors"
@@ -34,6 +36,18 @@ func (msg MsgSetRecord) ValidateBasic() error {
 	return nil
 }
 
+func (msg MsgRenewRecord) ValidateBasic() error {
+	if len(msg.RecordId) == 0 {
+		return errorsmod.Wrap(sdkerrors.ErrInvalidRequest, "record id is required.")
+	}
+
+	if len(msg.Signer) == 0 {
+		return errorsmod.Wrap(sdkerrors.ErrInvalidAddress, "invalid signer.")
+	}
+
+	return nil
+}
+
 // NewMsgReserveAuthority is the constructor function for MsgReserveName.
 func NewMsgReserveAuthority(name string, signer sdk.AccAddress, owner sdk.AccAddress) MsgReserveAuthority {
 	return MsgReserveAuthority{
@@ -65,6 +79,22 @@ func NewMsgSetAuthorityBond(name string, bondID string, signer sdk.AccAddress) M
 	}
 }
 
+func (msg MsgSetAuthorityBond) ValidateBasic() error {
+	if len(msg.Name) == 0 {
+		return errorsmod.Wrap(sdkerrors.ErrInvalidRequest, "name is required.")
+	}
+
+	if len(msg.Signer) == 0 {
+		return errorsmod.Wrap(sdkerrors.ErrInvalidAddress, "invalid signer.")
+	}
+
+	if len(msg.BondId) == 0 {
+		return errorsmod.Wrap(sdkerrors.ErrInvalidAddress, "bond id is required.")
+	}
+
+	return nil
+}
+
 // NewMsgSetName is the constructor function for MsgSetName.
 func NewMsgSetName(lrn string, cid string, signer sdk.AccAddress) *MsgSetName {
 	return &MsgSetName{
@@ -90,3 +120,70 @@ func (msg MsgSetName) ValidateBasic() error {
 
 	return nil
 }
+
+func (msg MsgDeleteNameAuthority) ValidateBasic() error {
+	if len(msg.Lrn) == 0 {
+		return errorsmod.Wrap(sdkerrors.ErrInvalidRequest, "lrn is required.")
+	}
+
+	if len(msg.Signer) == 0 {
+		return errorsmod.Wrap(sdkerrors.ErrInvalidAddress, "invalid signer.")
+	}
+
+	_, err := url.Parse(msg.Lrn)
+	if err != nil {
+		return errorsmod.Wrap(sdkerrors.ErrInvalidRequest, "invalid lrn.")
+	}
+
+	return nil
+}
+
+func (msg MsgAssociateBond) ValidateBasic() error {
+	if len(msg.RecordId) == 0 {
+		return errorsmod.Wrap(sdkerrors.ErrInvalidRequest, "record id is required.")
+	}
+	if len(msg.BondId) == 0 {
+		return errorsmod.Wrap(sdkerrors.ErrInvalidRequest, "bond id is required.")
+	}
+	if len(msg.Signer) == 0 {
+		return errorsmod.Wrap(sdkerrors.ErrInvalidAddress, "invalid signer.")
+	}
+
+	return nil
+}
+
+func (msg MsgDissociateBond) ValidateBasic() error {
+	if len(msg.RecordId) == 0 {
+		return errorsmod.Wrap(sdkerrors.ErrInvalidRequest, "record id is required.")
+	}
+	if len(msg.Signer) == 0 {
+		return errorsmod.Wrap(sdkerrors.ErrInvalidAddress, "invalid signer.")
+	}
+
+	return nil
+}
+
+func (msg MsgDissociateRecords) ValidateBasic() error {
+	if len(msg.BondId) == 0 {
+		return errorsmod.Wrap(sdkerrors.ErrInvalidRequest, "bond id is required.")
+	}
+	if len(msg.Signer) == 0 {
+		return errorsmod.Wrap(sdkerrors.ErrInvalidAddress, "invalid signer.")
+	}
+
+	return nil
+}
+
+func (msg MsgReassociateRecords) ValidateBasic() error {
+	if len(msg.OldBondId) == 0 {
+		return errorsmod.Wrap(sdkerrors.ErrInvalidRequest, "old-bond-id is required.")
+	}
+	if len(msg.NewBondId) == 0 {
+		return errorsmod.Wrap(sdkerrors.ErrInvalidRequest, "new-bond-id is required.")
+	}
+	if len(msg.Signer) == 0 {
+		return errorsmod.Wrap(sdkerrors.ErrInvalidAddress, "invalid signer.")
+	}
+
+	return nil
+}