refactor: improve address validator structure and make seal explicit

app/keepers.go

@@ -286,12 +286,13 @@ func initEvmKeeper(appCodec codec.Codec, keys map[string]*sdk.KVStoreKey, keeper
 func initNexusKeeper(appCodec codec.Codec, keys map[string]*sdk.KVStoreKey, keepers *keeperCache) *nexusKeeper.Keeper {
 	// setting validator will finalize all by sealing it
 	// no more validators can be added
-	addressValidator := nexusTypes.NewAddressValidator().
+	addressValidator := nexusTypes.NewAddressValidators().
 		AddAddressValidator(evmTypes.ModuleName, evmKeeper.NewAddressValidator()).
 		AddAddressValidator(axelarnetTypes.ModuleName, axelarnetKeeper.NewAddressValidator(getKeeper[axelarnetKeeper.Keeper](keepers)))
+	addressValidator.Seal()
 
 	nexusK := nexusKeeper.NewKeeper(appCodec, keys[nexusTypes.StoreKey], keepers.getSubspace(nexusTypes.ModuleName))
-	nexusK.SetAddressValidator(addressValidator)
+	nexusK.SetAddressValidators(addressValidator)
 
 	return &nexusK
 }

x/nexus/keeper/address.go

@@ -90,12 +90,12 @@ func (k Keeper) GetRecipient(ctx sdk.Context, depositAddress exported.CrossChain
 
 // ValidateAddress validates the given cross chain address
 func (k Keeper) ValidateAddress(ctx sdk.Context, address exported.CrossChainAddress) error {
-	validator := k.getAddressValidator().GetAddressValidator(address.Chain.Module)
-	if validator == nil {
-		return fmt.Errorf("unknown module for chain %s", address.Chain.String())
+	validate, err := k.getAddressValidator(address.Chain.Module)
+	if err != nil {
+		return err
 	}
 
-	if err := validator(ctx, address); err != nil {
+	if err := validate(ctx, address); err != nil {
 		return err
 	}
 

x/nexus/keeper/genesis_test.go

@@ -48,10 +48,12 @@ func setup() (sdk.Context, Keeper) {
 		},
 	}
 
-	router := types.NewAddressValidator()
-	router.AddAddressValidator(evmTypes.ModuleName, evmkeeper.NewAddressValidator()).
+	addressValidators := types.NewAddressValidators()
+	addressValidators.AddAddressValidator(evmTypes.ModuleName, evmkeeper.NewAddressValidator()).
 		AddAddressValidator(axelarnetTypes.ModuleName, axelarnetkeeper.NewAddressValidator(axelarnetK))
-	keeper.SetAddressValidator(router)
+
+	addressValidators.Seal()
+	keeper.SetAddressValidators(addressValidators)
 
 	return ctx, keeper
 }

x/nexus/keeper/grpc_query_test.go

@@ -62,13 +62,14 @@ func TestKeeper_TransfersForChain(t *testing.T) {
 			funcs.MustNoErr(k.RegisterAsset(ctx, evm.Ethereum, exported.NewAsset(axelarnet.NativeAsset, false), utils.MaxUint, time.Hour))
 			funcs.MustNoErr(k.RegisterAsset(ctx, axelarnet.Axelarnet, exported.NewAsset(axelarnet.NativeAsset, true), utils.MaxUint, time.Hour))
 
-			nexusRouter := types.NewAddressValidator().
+			addressValidators := types.NewAddressValidators().
 				AddAddressValidator("evm", func(sdk.Context, exported.CrossChainAddress) error {
 					return nil
 				}).AddAddressValidator("axelarnet", func(sdk.Context, exported.CrossChainAddress) error {
 				return nil
 			})
-			k.SetAddressValidator(nexusRouter)
+			addressValidators.Seal()
+			k.SetAddressValidators(addressValidators)
 
 		}).
 		When("there are some pending transfers", func() {

x/nexus/keeper/keeper.go

@@ -2,6 +2,7 @@ package keeper
 
 import (
 	"fmt"
+	"github.com/axelarnetwork/axelar-core/x/nexus/exported"
 
 	"github.com/cosmos/cosmos-sdk/codec"
 	sdk "github.com/cosmos/cosmos-sdk/types"
@@ -42,8 +43,8 @@ type Keeper struct {
 	cdc      codec.BinaryCodec
 	params   params.Subspace
 
-	addressValidator types.AddressValidator
-	messageRouter    types.MessageRouter
+	addressValidators *types.AddressValidators
+	messageRouter     types.MessageRouter
 }
 
 // NewKeeper returns a new nexus keeper
@@ -68,26 +69,25 @@ func (k Keeper) GetParams(ctx sdk.Context) types.Params {
 	return p
 }
 
-// SetAddressValidator sets the nexus address validator. It will panic if called more than once
-func (k *Keeper) SetAddressValidator(validator types.AddressValidator) {
-	if k.addressValidator != nil {
-		panic("validator already set")
+// SetAddressValidators sets the nexus address validator. It will panic if called more than once
+func (k *Keeper) SetAddressValidators(validators *types.AddressValidators) {
+	if !validators.IsSealed() {
+		panic("address validator must be sealed")
 	}
 
-	k.addressValidator = validator
+	if k.addressValidators != nil {
+		panic("address validator already set")
+	}
 
-	// In order to avoid invalid or non-deterministic behavior, we seal the validator immediately
-	// to prevent additionals handlers from being registered after the keeper is initialized.
-	k.addressValidator.Seal()
+	k.addressValidators = validators
 }
 
-// getAddressValidator returns the nexus address validator. If not set, it returns a sealed empty validator
-func (k Keeper) getAddressValidator() types.AddressValidator {
-	if k.addressValidator == nil {
-		k.SetAddressValidator(types.NewAddressValidator())
+func (k Keeper) getAddressValidator(module string) (exported.AddressValidator, error) {
+	if k.addressValidators == nil {
+		k.SetAddressValidators(types.NewAddressValidators())
 	}
 
-	return k.addressValidator
+	return k.addressValidators.GetAddressValidator(module)
 }
 
 func (k *Keeper) SetMessageRouter(router types.MessageRouter) {

x/nexus/keeper/keeper_test.go

@@ -31,7 +31,7 @@ const maxAmount int64 = 100000000000
 
 var k keeper.Keeper
 
-func addressValidator() types.AddressValidator {
+func addressValidators() *types.AddressValidators {
 	axelarnetK := &axelarnetmock.BaseKeeperMock{
 		GetCosmosChainByNameFunc: func(ctx sdk.Context, chain exported.ChainName) (axelarnetTypes.CosmosChain, bool) {
 			var prefix string
@@ -47,18 +47,20 @@ func addressValidator() types.AddressValidator {
 		},
 	}
 
-	router := types.NewAddressValidator()
-	router.AddAddressValidator(evmTypes.ModuleName, evmkeeper.NewAddressValidator()).
+	validators := types.NewAddressValidators()
+	validators.AddAddressValidator(evmTypes.ModuleName, evmkeeper.NewAddressValidator()).
 		AddAddressValidator(axelarnetTypes.ModuleName, axelarnetkeeper.NewAddressValidator(axelarnetK))
 
-	return router
+	validators.Seal()
+
+	return validators
 }
 
 func init() {
 	encCfg := app.MakeEncodingConfig()
 	subspace := params.NewSubspace(encCfg.Codec, encCfg.Amino, sdk.NewKVStoreKey("nexusKey"), sdk.NewKVStoreKey("tNexusKey"), "nexus")
 	k = keeper.NewKeeper(encCfg.Codec, sdk.NewKVStoreKey("nexus"), subspace)
-	k.SetAddressValidator(addressValidator())
+	k.SetAddressValidators(addressValidators())
 }
 
 func TestLinkAddress(t *testing.T) {

x/nexus/keeper/transfer_test.go

@@ -442,7 +442,7 @@ func setup(cfg params.EncodingConfig) (nexusKeeper.Keeper, sdk.Context) {
 	ctx := sdk.NewContext(fake.NewMultiStore(), tmproto.Header{}, false, log.TestingLogger())
 
 	k.SetParams(ctx, types.DefaultParams())
-	k.SetAddressValidator(addressValidator())
+	k.SetAddressValidators(addressValidators())
 
 	// register asset in ChainState
 	for _, chain := range chains {

x/nexus/types/address_validator.go

@@ -6,36 +6,36 @@ import (
 	"github.com/axelarnetwork/axelar-core/x/nexus/exported"
 )
 
-// AddressValidator implements a AddressValidator based on module name.
-type AddressValidator interface {
-	AddAddressValidator(module string, validator exported.AddressValidator) AddressValidator
-	HasAddressValidator(module string) bool
-	GetAddressValidator(module string) exported.AddressValidator
-	Seal()
-}
-
-var _ AddressValidator = (*addressValidator)(nil)
-
-type addressValidator struct {
+// AddressValidators collects all registered address validators by module
+type AddressValidators struct {
 	validators map[string]exported.AddressValidator
 	sealed     bool
 }
 
-// NewAddressValidator creates a new AddressValidator interface instance
-func NewAddressValidator() AddressValidator {
-	return &addressValidator{
+// NewAddressValidators returns a new AddressValidators instance
+func NewAddressValidators() *AddressValidators {
+	return &AddressValidators{
 		validators: make(map[string]exported.AddressValidator),
 	}
 }
 
 // Seal prevents additional validators from being added
-func (r *addressValidator) Seal() {
+func (r *AddressValidators) Seal() {
+	if r.sealed {
+		panic("cannot seal address validator (validator already sealed)")
+	}
+
 	r.sealed = true
 }
 
+// IsSealed returns true if the validator is sealed
+func (r *AddressValidators) IsSealed() bool {
+	return r.sealed
+}
+
 // AddAddressValidator registers a validator for a given path
 // panics if the validator is sealed, module is an empty string, or if the module has been registered already
-func (r *addressValidator) AddAddressValidator(module string, validator exported.AddressValidator) AddressValidator {
+func (r *AddressValidators) AddAddressValidator(module string, validator exported.AddressValidator) *AddressValidators {
 	if r.sealed {
 		panic("cannot add validator (validator sealed)")
 	}
@@ -53,15 +53,16 @@ func (r *addressValidator) AddAddressValidator(module string, validator exported
 }
 
 // HasAddressValidator returns true if a validator is registered for the given module
-func (r *addressValidator) HasAddressValidator(module string) bool {
-	return r.validators[module] != nil
+func (r *AddressValidators) HasAddressValidator(module string) bool {
+	_, err := r.GetAddressValidator(module)
+	return err == nil
 }
 
 // GetAddressValidator returns a validator for a given module
-func (r *addressValidator) GetAddressValidator(module string) exported.AddressValidator {
-	if !r.HasAddressValidator(module) {
-		panic(fmt.Sprintf("validator for module \"%s\" not registered", module))
+func (r *AddressValidators) GetAddressValidator(module string) (exported.AddressValidator, error) {
+	validate, ok := r.validators[module]
+	if !ok || validate == nil {
+		return nil, fmt.Errorf("validator for module \"%s\" not registered", module)
 	}
-
-	return r.validators[module]
+	return validate, nil
 }