Handle hex strings and quoted strings in HTTP params

Use 0x-prefixed hex strings in client

server: Decode hex string args

Encode all string args as 0x<hex> without trying to encode as JSON

Added tests for special string arguments

Fix server handling quoted string args

Added string arg handling test cases to bash test script

client/http_client.go

@@ -4,10 +4,12 @@ import (
 	"bytes"
 	"encoding/json"
 	"errors"
+	"fmt"
 	"io/ioutil"
 	"net"
 	"net/http"
 	"net/url"
+	"reflect"
 	"strings"
 
 	. "github.com/tendermint/go-common"
@@ -119,7 +121,7 @@ func (c *ClientURI) call(method string, params map[string]interface{}, result in
 	if err != nil {
 		return nil, err
 	}
-	//log.Info(Fmt("URI request to %v (%v): %v", c.address, method, values))
+	log.Info(Fmt("URI request to %v (%v): %v", c.address, method, values))
 	resp, err := c.client.PostForm(c.address+"/"+method, values)
 	if err != nil {
 		return nil, err
@@ -176,6 +178,21 @@ func argsToJson(args map[string]interface{}) error {
 	var n int
 	var err error
 	for k, v := range args {
+		// Convert strings to "0x"-prefixed hex
+		str, isString := reflect.ValueOf(v).Interface().(string)
+		if isString {
+			args[k] = fmt.Sprintf("0x%X", str)
+			continue
+		}
+
+		// Convert byte slices to "0x"-prefixed hex
+		byteSlice, isByteSlice := reflect.ValueOf(v).Interface().([]byte)
+		if isByteSlice {
+			args[k] = fmt.Sprintf("0x%X", byteSlice)
+			continue
+		}
+
+		// Pass everything else to go-wire
 		buf := new(bytes.Buffer)
 		wire.WriteJSON(v, buf, &n, &err)
 		if err != nil {

rpc_test.go

@@ -164,3 +164,39 @@ func TestWS_UNIX(t *testing.T) {
 	}
 	testWS(t, cl)
 }
+
+func TestHexStringArg(t *testing.T) {
+	cl := rpcclient.NewClientURI(tcpAddr)
+	// should NOT be handled as hex
+	val := "0xabc"
+	params := map[string]interface{}{
+		"arg": val,
+	}
+	var result Result
+	_, err := cl.Call("status", params, &result)
+	if err != nil {
+		t.Fatal(err)
+	}
+	got := result.(*ResultStatus).Value
+	if got != val {
+		t.Fatalf("Got: %v   ....   Expected: %v \n", got, val)
+	}
+}
+
+func TestQuotedStringArg(t *testing.T) {
+	cl := rpcclient.NewClientURI(tcpAddr)
+	// should NOT be unquoted
+	val := "\"abc\""
+	params := map[string]interface{}{
+		"arg": val,
+	}
+	var result Result
+	_, err := cl.Call("status", params, &result)
+	if err != nil {
+		t.Fatal(err)
+	}
+	got := result.(*ResultStatus).Value
+	if got != val {
+		t.Fatalf("Got: %v   ....   Expected: %v \n", got, val)
+	}
+}

server/handlers.go

@@ -2,6 +2,7 @@ package rpcserver
 
 import (
 	"bytes"
+	"encoding/hex"
 	"encoding/json"
 	"errors"
 	"fmt"
@@ -229,7 +230,35 @@ func httpParamsToArgs(rpcFunc *RPCFunc, r *http.Request) ([]reflect.Value, error
 	for i, name := range argNames {
 		ty := argTypes[i]
 		arg := GetParam(r, name)
-		//log.Notice("param to arg", "ty", ty, "name", name, "arg", arg)
+		// log.Notice("param to arg", "ty", ty, "name", name, "arg", arg)
+
+		// Handle quoted strings
+		if strings.HasPrefix(arg, "\"") && strings.HasSuffix(arg, "\"") {
+			data := arg[1 : len(arg)-1]
+			if ty.Kind() == reflect.String {
+				values[i] = reflect.ValueOf(string(data))
+			} else {
+				values[i] = reflect.ValueOf(data)
+			}
+			continue
+		}
+
+		// Handle hex strings
+		if strings.HasPrefix(strings.ToLower(arg), "0x") {
+			var value []byte
+			value, err = hex.DecodeString(arg[2:])
+			if err != nil {
+				return nil, err
+			}
+			if ty.Kind() == reflect.String {
+				values[i] = reflect.ValueOf(string(value))
+			} else {
+				values[i] = reflect.ValueOf(value)
+			}
+			continue
+		}
+
+		// Pass values to go-wire
 		values[i], err = _jsonStringToArg(ty, arg)
 		if err != nil {
 			return nil, err

test/test.sh

@@ -6,18 +6,37 @@ go build -o server main.go
 PID=$!
 sleep 2
 
-
+# simple JSONRPC request
 R1=`curl -s 'http://localhost:8008/hello_world?name="my_world"&num=5'`
-
-
 R2=`curl -s --data @data.json http://localhost:8008`
-
-kill -9 $PID
-
 if [[ "$R1" != "$R2" ]]; then
 	echo "responses are not identical:"
 	echo "R1: $R1"
 	echo "R2: $R2"
-	exit 1
+else
+	echo "Success"
 fi
-echo "Success"
+
+# request with 0x-prefixed hex string arg
+R1=`curl -s 'http://localhost:8008/hello_world?name=0x41424344&num=123'`
+R2='{"jsonrpc":"2.0","id":"","result":{"Result":"hi ABCD 123"},"error":""}'
+if [[ "$R1" != "$R2" ]]; then
+	echo "responses are not identical:"
+	echo "R1: $R1"
+	echo "R2: $R2"
+else
+	echo "Success"
+fi
+
+# request with unquoted string arg
+R1=`curl -s 'http://localhost:8008/hello_world?name=abcd&num=123'`
+R2="{\"jsonrpc\":\"2.0\",\"id\":\"\",\"result\":null,\"error\":\"Error converting http params to args: invalid character 'a' looking for beginning of value\"}"
+if [[ "$R1" != "$R2" ]]; then
+	echo "responses are not identical:"
+	echo "R1: $R1"
+	echo "R2: $R2"
+else
+	echo "Success"
+fi
+
+kill -9 $PID