rpc: encode port numbers as proper numbers in getpeers

The way C# node does it.

pkg/rpc/client/rpc_test.go

@@ -517,25 +517,25 @@ var rpcClientTestCases = map[string][]rpcClientTestCase{
 			invoke: func(c *Client) (interface{}, error) {
 				return c.GetPeers()
 			},
-			serverResponse: `{"id":1,"jsonrpc":"2.0","result":{"unconnected":[{"address":"172.200.0.1","port":"20333"}],"connected":[{"address":"127.0.0.1","port":"20335"}],"bad":[{"address":"172.200.0.254","port":"20332"}]}}`,
+			serverResponse: `{"id":1,"jsonrpc":"2.0","result":{"unconnected":[{"address":"172.200.0.1","port":20333}],"connected":[{"address":"127.0.0.1","port":20335}],"bad":[{"address":"172.200.0.254","port":20332}]}}`,
 			result: func(c *Client) interface{} {
 				return &result.GetPeers{
 					Unconnected: result.Peers{
 						{
 							Address: "172.200.0.1",
-							Port:    "20333",
+							Port:    20333,
 						},
 					},
 					Connected: result.Peers{
 						{
 							Address: "127.0.0.1",
-							Port:    "20335",
+							Port:    20335,
 						},
 					},
 					Bad: result.Peers{
 						{
 							Address: "172.200.0.254",
-							Port:    "20332",
+							Port:    20332,
 						},
 					},
 				}

pkg/rpc/response/result/peers.go

@@ -1,6 +1,7 @@
 package result
 
 import (
+	"strconv"
 	"strings"
 )
 
@@ -18,7 +19,7 @@ type (
 	// Peer represents the peer.
 	Peer struct {
 		Address string `json:"address"`
-		Port    string `json:"port"`
+		Port    uint16 `json:"port"`
 	}
 )
 
@@ -50,9 +51,10 @@ func (g *GetPeers) AddBad(addrs []string) {
 func (p *Peers) addPeers(addrs []string) {
 	for i := range addrs {
 		addressParts := strings.Split(addrs[i], ":")
+		port, _ := strconv.Atoi(addressParts[1]) // We know it's a good port number.
 		peer := Peer{
 			Address: addressParts[0],
-			Port:    addressParts[1],
+			Port:    uint16(port),
 		}
 
 		*p = append(*p, peer)

pkg/rpc/response/result/peers_test.go

@@ -20,7 +20,7 @@ func TestGetPeers(t *testing.T) {
 	require.Equal(t, 1, len(gp.Connected))
 	require.Equal(t, 1, len(gp.Bad))
 	require.Equal(t, "192.168.0.1", gp.Connected[0].Address)
-	require.Equal(t, "10333", gp.Connected[0].Port)
+	require.Equal(t, uint16(10333), gp.Connected[0].Port)
 	require.Equal(t, "127.0.0.1", gp.Bad[0].Address)
-	require.Equal(t, "20333", gp.Bad[0].Port)
+	require.Equal(t, uint16(20333), gp.Bad[0].Port)
 }