Implements eth_getProof (#122)

* Implemented eth_getProof and cleaned logs query types

* Rename ethereum logs query type

go.mod

@@ -53,7 +53,6 @@ require (
 	golang.org/x/net v0.0.0-20190628185345-da137c7871d7
 	golang.org/x/sys v0.0.0-20190626221950-04f50cda93cb // indirect
 	golang.org/x/text v0.3.2 // indirect
-	google.golang.org/appengine v1.4.0 // indirect
 	google.golang.org/genproto v0.0.0-20190708153700-3bdd9d9f5532 // indirect
 	gopkg.in/natefinch/npipe.v2 v2.0.0-20160621034901-c1b8fa8bdcce // indirect
 	gopkg.in/yaml.v2 v2.2.2

rpc/eth_api.go

@@ -14,6 +14,7 @@ import (
 	"github.com/cosmos/ethermint/x/evm"
 	"github.com/cosmos/ethermint/x/evm/types"
 
+	"github.com/tendermint/tendermint/rpc/client"
 	tmtypes "github.com/tendermint/tendermint/types"
 
 	"github.com/ethereum/go-ethereum/accounts/keystore"
@@ -599,7 +600,7 @@ func (e *PublicEthAPI) GetTransactionReceipt(hash common.Hash) (map[string]inter
 		return nil, err
 	}
 
-	var logs types.QueryTxLogs
+	var logs types.QueryETHLogs
 	e.cliCtx.Codec.MustUnmarshalJSON(res, &logs)
 
 	// TODO: change hard coded indexing of bytes
@@ -639,6 +640,68 @@ func (e *PublicEthAPI) GetUncleByBlockNumberAndIndex(number hexutil.Uint, idx he
 	return nil
 }
 
+// AccountResult struct for account proof
+type AccountResult struct {
+	Address      common.Address  `json:"address"`
+	AccountProof []string        `json:"accountProof"`
+	Balance      *hexutil.Big    `json:"balance"`
+	CodeHash     common.Hash     `json:"codeHash"`
+	Nonce        hexutil.Uint64  `json:"nonce"`
+	StorageHash  common.Hash     `json:"storageHash"`
+	StorageProof []StorageResult `json:"storageProof"`
+}
+
+// StorageResult defines the format for storage proof return
+type StorageResult struct {
+	Key   string       `json:"key"`
+	Value *hexutil.Big `json:"value"`
+	Proof []string     `json:"proof"`
+}
+
+// GetProof returns an account object with proof and any storage proofs
+func (e *PublicEthAPI) GetProof(address common.Address, storageKeys []string, block BlockNumber) (*AccountResult, error) {
+	opts := client.ABCIQueryOptions{Height: int64(block), Prove: true}
+	path := fmt.Sprintf("custom/%s/%s/%s", types.ModuleName, evm.QueryAccount, address.Hex())
+	pRes, err := e.cliCtx.Client.ABCIQueryWithOptions(path, nil, opts)
+	if err != nil {
+		return nil, err
+	}
+
+	// TODO: convert TM merkle proof to []string if needed in future
+	// proof := pRes.Response.GetProof()
+
+	account := new(types.QueryAccount)
+	e.cliCtx.Codec.MustUnmarshalJSON(pRes.Response.GetValue(), &account)
+
+	storageProofs := make([]StorageResult, len(storageKeys))
+	for i, k := range storageKeys {
+		// Get value for key
+		vPath := fmt.Sprintf("custom/%s/%s/%s/%s", types.ModuleName, evm.QueryStorage, address, k)
+		vRes, err := e.cliCtx.Client.ABCIQueryWithOptions(vPath, nil, opts)
+		if err != nil {
+			return nil, err
+		}
+		value := new(types.QueryResStorage)
+		e.cliCtx.Codec.MustUnmarshalJSON(vRes.Response.GetValue(), &value)
+
+		storageProofs[i] = StorageResult{
+			Key:   k,
+			Value: (*hexutil.Big)(common.BytesToHash(value.Value).Big()),
+			Proof: []string{""},
+		}
+	}
+
+	return &AccountResult{
+		Address:      address,
+		AccountProof: []string{""}, // This shouldn't be necessary (different proof formats)
+		Balance:      (*hexutil.Big)(utils.MustUnmarshalBigInt(account.Balance)),
+		CodeHash:     common.BytesToHash(account.CodeHash),
+		Nonce:        hexutil.Uint64(account.Nonce),
+		StorageHash:  common.Hash{}, // Ethermint doesn't have a storage hash
+		StorageProof: storageProofs,
+	}, nil
+}
+
 // getGasLimit returns the gas limit per block set in genesis
 func (e *PublicEthAPI) getGasLimit() (int64, error) {
 	// Retrieve from gasLimit variable cache

utils/int.go

@@ -17,3 +17,13 @@ func UnmarshalBigInt(s string) (*big.Int, error) {
 	err := ret.UnmarshalText([]byte(s))
 	return ret, err
 }
+
+// MustUnmarshalBigInt unmarshalls string from *big.Int
+func MustUnmarshalBigInt(s string) *big.Int {
+	ret := new(big.Int)
+	err := ret.UnmarshalText([]byte(s))
+	if err != nil {
+		panic(err)
+	}
+	return ret
+}

x/evm/querier.go

@@ -25,6 +25,7 @@ const (
 	QueryTxLogs          = "txLogs"
 	QueryLogsBloom       = "logsBloom"
 	QueryLogs            = "logs"
+	QueryAccount         = "account"
 )
 
 // NewQuerier is the module level router for state queries
@@ -50,7 +51,9 @@ func NewQuerier(keeper Keeper) sdk.Querier {
 		case QueryLogsBloom:
 			return queryBlockLogsBloom(ctx, path, keeper)
 		case QueryLogs:
-			return queryLogs(ctx, path, keeper)
+			return queryLogs(ctx, keeper)
+		case QueryAccount:
+			return queryAccount(ctx, path, keeper)
 		default:
 			return nil, sdk.ErrUnknownRequest("unknown query endpoint")
 		}
@@ -162,7 +165,7 @@ func queryTxLogs(ctx sdk.Context, path []string, keeper Keeper) ([]byte, sdk.Err
 	txHash := ethcmn.HexToHash(path[1])
 	logs := keeper.GetLogs(ctx, txHash)
 
-	bRes := types.QueryTxLogs{Logs: logs}
+	bRes := types.QueryETHLogs{Logs: logs}
 	res, err := codec.MarshalJSONIndent(keeper.cdc, bRes)
 	if err != nil {
 		panic("could not marshal result to JSON: " + err.Error())
@@ -171,10 +174,27 @@ func queryTxLogs(ctx sdk.Context, path []string, keeper Keeper) ([]byte, sdk.Err
 	return res, nil
 }
 
-func queryLogs(ctx sdk.Context, path []string, keeper Keeper) ([]byte, sdk.Error) {
+func queryLogs(ctx sdk.Context, keeper Keeper) ([]byte, sdk.Error) {
 	logs := keeper.Logs(ctx)
 
-	l, err := codec.MarshalJSONIndent(keeper.cdc, logs)
+	lRes := types.QueryETHLogs{Logs: logs}
+	l, err := codec.MarshalJSONIndent(keeper.cdc, lRes)
+	if err != nil {
+		panic("could not marshal result to JSON: " + err.Error())
+	}
+	return l, nil
+}
+
+func queryAccount(ctx sdk.Context, path []string, keeper Keeper) ([]byte, sdk.Error) {
+	addr := ethcmn.HexToAddress(path[1])
+	so := keeper.GetOrNewStateObject(ctx, addr)
+
+	lRes := types.QueryAccount{
+		Balance:  utils.MarshalBigInt(so.Balance()),
+		CodeHash: so.CodeHash(),
+		Nonce:    so.Nonce(),
+	}
+	l, err := codec.MarshalJSONIndent(keeper.cdc, lRes)
 	if err != nil {
 		panic("could not marshal result to JSON: " + err.Error())
 	}

x/evm/types/querier.go

@@ -60,12 +60,12 @@ func (q QueryResNonce) String() string {
 	return string(q.Nonce)
 }
 
-// QueryTxLogs is response type for tx logs query
+// QueryETHLogs is response type for tx logs query
-type QueryTxLogs struct {
+type QueryETHLogs struct {
 	Logs []*ethtypes.Log `json:"logs"`
 }
 
-func (q QueryTxLogs) String() string {
+func (q QueryETHLogs) String() string {
 	return string(fmt.Sprintf("%+v", q.Logs))
 }
 
@@ -77,3 +77,10 @@ type QueryBloomFilter struct {
 func (q QueryBloomFilter) String() string {
 	return string(q.Bloom.Bytes())
 }
+
+// QueryAccount is response type for querying Ethereum state objects
+type QueryAccount struct {
+	Balance  string `json:"balance"`
+	CodeHash []byte `json:"codeHash"`
+	Nonce    uint64 `json:"nonce"`
+}