R4R: Fix /txs/encode endpoint (#4212)

Closes: #4141

.pending/improvements/gaiarest/4141-Fix-txs-encode-

@@ -0,0 +1 @@
+#4141 Fix /txs/encode endpoint

client/tx/encode.go

@@ -18,9 +18,7 @@ import (
 
 type (
 	// EncodeReq defines a tx encoding request.
-	EncodeReq struct {
-		Tx auth.StdTx `json:"tx"`
-	}
+	// Use auth.StdTx directly
 
 	// EncodeResp defines a tx encoding response.
 	EncodeResp struct {
@@ -33,7 +31,7 @@ type (
 // and responds with base64-encoded bytes.
 func EncodeTxRequestHandlerFn(cdc *codec.Codec, cliCtx context.CLIContext) http.HandlerFunc {
 	return func(w http.ResponseWriter, r *http.Request) {
-		var req EncodeReq
+		var req auth.StdTx
 
 		body, err := ioutil.ReadAll(r.Body)
 		if err != nil {
@@ -48,7 +46,7 @@ func EncodeTxRequestHandlerFn(cdc *codec.Codec, cliCtx context.CLIContext) http.
 		}
 
 		// re-encode it via the Amino wire protocol
-		txBytes, err := cliCtx.Codec.MarshalBinaryLengthPrefixed(req.Tx)
+		txBytes, err := cliCtx.Codec.MarshalBinaryLengthPrefixed(req)
 		if err != nil {
 			rest.WriteErrorResponse(w, http.StatusInternalServerError, err.Error())
 			return

cmd/gaia/lcd_test/lcd_test.go

@@ -18,7 +18,6 @@ import (
 
 	"github.com/cosmos/cosmos-sdk/client"
 	"github.com/cosmos/cosmos-sdk/client/keys"
-	clienttx "github.com/cosmos/cosmos-sdk/client/tx"
 	"github.com/cosmos/cosmos-sdk/crypto/keys/mintkey"
 	"github.com/cosmos/cosmos-sdk/tests"
 	sdk "github.com/cosmos/cosmos-sdk/types"
@@ -291,10 +290,9 @@ func TestEncodeTx(t *testing.T) {
 
 	res, body, _ := doTransferWithGas(t, port, seed, name1, memo, "", addr, "2", 1, false, false, fees)
 	var tx auth.StdTx
-	cdc.UnmarshalJSON([]byte(body), &tx)
+	require.Nil(t, cdc.UnmarshalJSON([]byte(body), &tx))
 
-	req := clienttx.EncodeReq{Tx: tx}
-	encodedJSON, _ := cdc.MarshalJSON(req)
+	encodedJSON, _ := cdc.MarshalJSON(tx)
 	res, body = Request(t, port, "POST", "/txs/encode", encodedJSON)
 
 	// Make sure it came back ok, and that we can decode it back to the transaction