From 649a9c2d1ad91cc0ba14134a00668f905fe52973 Mon Sep 17 00:00:00 2001
From: Tuan Pham Anh <baabeetaa@gmail.com>
Date: Thu, 6 Apr 2023 17:34:05 +0700
Subject: [PATCH] fix: jsonrpc to support both positional parameters and named
 parameters https://github.com/notional-labs/subnode/issues/15

---
 config_test.go     |  2 +-
 rpc_server.go      | 60 +++++++++++++++++++++++++++++++++++-----------
 rpc_server_test.go | 26 ++++++++++++++++++++
 state_test.go      |  4 ++--
 4 files changed, 75 insertions(+), 17 deletions(-)
 create mode 100644 rpc_server_test.go

diff --git a/config_test.go b/config_test.go
index 2b2c912..b9f1c9f 100644
--- a/config_test.go
+++ b/config_test.go
@@ -24,7 +24,7 @@ upstream:
 func TestGetBackendNodeType(t *testing.T) {
 	b := Backend{
 		Rpc:    "http://pruned",
-		Blocks: []int{10},
+		Blocks: []int64{10},
 	}
 
 	assert.Equal(t, GetBackendNodeType(&b), BackendNodeTypePruned)
diff --git a/rpc_server.go b/rpc_server.go
index 4047ba0..a0811e3 100644
--- a/rpc_server.go
+++ b/rpc_server.go
@@ -79,9 +79,13 @@ func StartRpcServer() {
 
 			m0 := j0.(map[string]interface{})
 			method := m0["method"].(string)
-			params := m0["params"].([]interface{})
+			//params := m0["params"].([]interface{})
 
-			fmt.Printf("method=%s, params=%+v\n", method, params)
+			fmt.Printf("method=%s, params=%+v\n", method, m0["params"])
+
+			// note that params could be positional parameters or named parameters
+			// eg.,  "params": [ "9045128", "1", "30" ]
+			//   or  "params": { "height": "9045128", "page": "1", "per_page": "30" }
 
 			if method == "abci_info" ||
 				strings.HasPrefix(method, "broadcast_") ||
@@ -105,14 +109,28 @@ func StartRpcServer() {
 				method == "consensus_params" ||
 				method == "validators" {
 
-				// height is 1st param
-				if len(params) < 1 {
-					SendError(w)
+				height := int64(0)
+
+				if positionalParams, ok := m0["params"].([]interface{}); ok { // positional parameters
+					// height is 1st param
+					if len(positionalParams) < 1 {
+						SendError(w)
+					}
+
+					heightParam := positionalParams[0].(string)
+					height, err = strconv.ParseInt(heightParam, 10, 64)
+					if err != nil {
+						SendError(w)
+					}
+				} else if namedParams, ok := m0["params"].(map[string]interface{}); ok { // named parameters
+					heightParam := namedParams["height"].(string)
+					height, err = strconv.ParseInt(heightParam, 10, 64)
+					if err != nil {
+						SendError(w)
+					}
 				}
 
-				heightParam := params[0].(string)
-				height, err := strconv.ParseInt(heightParam, 10, 64)
-				if err != nil {
+				if height == 0 {
 					SendError(w)
 				}
 
@@ -123,14 +141,28 @@ func StartRpcServer() {
 
 				selectedHost = node.Backend.Rpc
 			} else if method == "abci_query" {
-				// height is 3rd param
-				if len(params) < 3 {
-					SendError(w)
+				height := int64(0)
+
+				if positionalParams, ok := m0["params"].([]interface{}); ok { // positional parameters
+					// height is 3rd param
+					if len(positionalParams) < 3 {
+						SendError(w)
+					}
+
+					heightParam := positionalParams[2].(string)
+					height, err = strconv.ParseInt(heightParam, 10, 64)
+					if err != nil {
+						SendError(w)
+					}
+				} else if namedParams, ok := m0["params"].(map[string]interface{}); ok { // named parameters
+					heightParam := namedParams["height"].(string)
+					height, err = strconv.ParseInt(heightParam, 10, 64)
+					if err != nil {
+						SendError(w)
+					}
 				}
 
-				heightParam := params[2].(string)
-				height, err := strconv.ParseInt(heightParam, 10, 64)
-				if err != nil {
+				if height == 0 {
 					SendError(w)
 				}
 
diff --git a/rpc_server_test.go b/rpc_server_test.go
new file mode 100644
index 0000000..e3a512b
--- /dev/null
+++ b/rpc_server_test.go
@@ -0,0 +1,26 @@
+package main
+
+import (
+	"encoding/json"
+	"fmt"
+	"github.com/stretchr/testify/assert"
+	"reflect"
+	"testing"
+)
+
+func TestJsonRpcParams(t *testing.T) {
+	jsonText := []byte(`{"jsonrpc": "2.0", "id": "0", "method": "validators", "params": { "height": "9045128", "page": "1", "per_page": "30" }}`)
+	//jsonText := []byte(`{"jsonrpc": "2.0", "id": "0", "method": "validators", "params": ["9045128", "1", "30"]}`)
+
+	var j0 interface{}
+	err := json.Unmarshal(jsonText, &j0)
+	assert.NoError(t, err)
+
+	m0 := j0.(map[string]interface{})
+	//method := m0["method"].(string)
+	//params := m0["params"].([]interface{})
+	//
+	//fmt.Printf("method=%s, params=%+v\n", method, params)
+
+	fmt.Println(reflect.TypeOf(m0["params"]))
+}
diff --git a/state_test.go b/state_test.go
index 0ffa408..fb657d6 100644
--- a/state_test.go
+++ b/state_test.go
@@ -8,11 +8,11 @@ import (
 func TestSelectPrunedNode(t *testing.T) {
 	pruned := Backend{
 		Rpc:    "http://pruned",
-		Blocks: []int{10},
+		Blocks: []int64{10},
 	}
 	archive := Backend{
 		Rpc:    "http://archive",
-		Blocks: []int{},
+		Blocks: []int64{},
 	}
 
 	cfg = &Config{