client: add GetAccount and GetAccountWithHeight to AccountRetriever (#7558)

* client: add GetAccount and GetAccountWithHeight to AccountRetriever

* update ADR

* address comments from review

client/account_retriever.go

@@ -1,11 +1,25 @@
 package client
 
-import "github.com/cosmos/cosmos-sdk/types"
+import (
+	"github.com/tendermint/tendermint/crypto"
+
+	sdk "github.com/cosmos/cosmos-sdk/types"
+)
+
+// Account defines a read-only version of the auth module's AccountI.
+type Account interface {
+	GetAddress() sdk.AccAddress
+	GetPubKey() crypto.PubKey // can return nil.
+	GetAccountNumber() uint64
+	GetSequence() uint64
+}
 
 // AccountRetriever defines the interfaces required by transactions to
 // ensure an account exists and to be able to query for account fields necessary
 // for signing.
 type AccountRetriever interface {
-	EnsureExists(clientCtx Context, addr types.AccAddress) error
-	GetAccountNumberSequence(clientCtx Context, addr types.AccAddress) (accNum uint64, accSeq uint64, err error)
+	GetAccount(clientCtx Context, addr sdk.AccAddress) (Account, error)
+	GetAccountWithHeight(clientCtx Context, addr sdk.AccAddress) (Account, int64, error)
+	EnsureExists(clientCtx Context, addr sdk.AccAddress) error
+	GetAccountNumberSequence(clientCtx Context, addr sdk.AccAddress) (accNum uint64, accSeq uint64, err error)
 }

client/test_helpers.go

@@ -3,19 +3,67 @@ package client
 import (
 	"fmt"
 
+	"github.com/tendermint/tendermint/crypto"
+
 	sdk "github.com/cosmos/cosmos-sdk/types"
 )
 
-// TestAccountRetriever is an AccountRetriever that can be used in unit tests
-type TestAccountRetriever struct {
-	Accounts map[string]struct {
-		Address sdk.AccAddress
-		Num     uint64
-		Seq     uint64
-	}
+var (
+	_ AccountRetriever = TestAccountRetriever{}
+	_ Account          = TestAccount{}
+)
+
+// TestAccount represents a client Account that can be used in unit tests
+type TestAccount struct {
+	Address sdk.AccAddress
+	Num     uint64
+	Seq     uint64
 }
 
-var _ AccountRetriever = TestAccountRetriever{}
+// GetAddress implements client Account.GetAddress
+func (t TestAccount) GetAddress() sdk.AccAddress {
+	return t.Address
+}
+
+// GetPubKey implements client Account.GetPubKey
+func (t TestAccount) GetPubKey() crypto.PubKey {
+	return nil
+}
+
+// GetAccountNumber implements client Account.GetAccountNumber
+func (t TestAccount) GetAccountNumber() uint64 {
+	return t.Num
+}
+
+// GetSequence implements client Account.GetSequence
+func (t TestAccount) GetSequence() uint64 {
+	return t.Seq
+}
+
+// TestAccountRetriever is an AccountRetriever that can be used in unit tests
+type TestAccountRetriever struct {
+	Accounts map[string]TestAccount
+}
+
+// GetAccount implements AccountRetriever.GetAccount
+func (t TestAccountRetriever) GetAccount(_ Context, addr sdk.AccAddress) (Account, error) {
+	acc, ok := t.Accounts[addr.String()]
+	if !ok {
+		return nil, fmt.Errorf("account %s not found", addr)
+	}
+
+	return acc, nil
+}
+
+// GetAccountWithHeight implements AccountRetriever.GetAccountWithHeight
+func (t TestAccountRetriever) GetAccountWithHeight(clientCtx Context, addr sdk.AccAddress) (Account, int64, error) {
+	acc, err := t.GetAccount(clientCtx, addr)
+	if err != nil {
+		return nil, 0, err
+	}
+
+	return acc, 0, nil
+}
 
 // EnsureExists implements AccountRetriever.EnsureExists
 func (t TestAccountRetriever) EnsureExists(_ Context, addr sdk.AccAddress) error {

docs/architecture/adr-020-protobuf-transaction-encoding.md

@@ -11,6 +11,7 @@
 - 2020 August 07: Use ADR 027 for serializing `SignDoc`.
 - 2020 August 19: Move sequence field from `SignDoc` to `SignerInfo`.
 - 2020 September 25: Remove `PublicKey` type in favor of `secp256k1.PubKey`, `ed25519.PubKey` and `multisig.LegacyAminoPubKey`.
+- 2020 October 15: Add `GetAccount` and `GetAccountWithHeight` methods to the `AccountRetriever` interface.
 
 ## Status
 
@@ -315,6 +316,8 @@ and messages.
 
 ```go
 type AccountRetriever interface {
+  GetAccount(clientCtx Context, addr sdk.AccAddress) (client.Account, error)
+  GetAccountWithHeight(clientCtx Context, addr sdk.AccAddress) (client.Account, int64, error)
   EnsureExists(clientCtx client.Context, addr sdk.AccAddress) error
   GetAccountNumberSequence(clientCtx client.Context, addr sdk.AccAddress) (uint64, uint64, error)
 }

x/auth/types/account_retriever.go

@@ -13,13 +13,18 @@ import (
 	grpctypes "github.com/cosmos/cosmos-sdk/types/grpc"
 )
 
+var (
+	_ client.Account          = AccountI(nil)
+	_ client.AccountRetriever = AccountRetriever{}
+)
+
 // AccountRetriever defines the properties of a type that can be used to
 // retrieve accounts.
 type AccountRetriever struct{}
 
 // GetAccount queries for an account given an address and a block height. An
 // error is returned if the query or decoding fails.
-func (ar AccountRetriever) GetAccount(clientCtx client.Context, addr sdk.AccAddress) (AccountI, error) {
+func (ar AccountRetriever) GetAccount(clientCtx client.Context, addr sdk.AccAddress) (client.Account, error) {
 	account, _, err := ar.GetAccountWithHeight(clientCtx, addr)
 	return account, err
 }
@@ -28,7 +33,7 @@ func (ar AccountRetriever) GetAccount(clientCtx client.Context, addr sdk.AccAddr
 // height of the query with the account. An error is returned if the query
 // or decoding fails.
 //nolint:interfacer
-func (ar AccountRetriever) GetAccountWithHeight(clientCtx client.Context, addr sdk.AccAddress) (AccountI, int64, error) {
+func (ar AccountRetriever) GetAccountWithHeight(clientCtx client.Context, addr sdk.AccAddress) (client.Account, int64, error) {
 	var header metadata.MD
 
 	queryClient := NewQueryClient(clientCtx)