kaspad/cmd/jsonrpcifyer/server.go

130 lines
3.1 KiB
Go

package main
import (
"encoding/json"
"errors"
"fmt"
"io/ioutil"
"log"
"net/http"
"strings"
"github.com/daglabs/btcd/rpcclient"
)
type server struct {
cfg *config
rpcConnConfig *rpcclient.ConnConfig
httpServer *http.Server
rpcClient *rpcclient.Client
}
func newServer(cfg *config) (*server, error) {
server := server{
cfg: cfg,
}
server.rpcConnConfig = &rpcclient.ConnConfig{
Host: cfg.Host,
Endpoint: "ws",
User: cfg.RPCUser,
Pass: cfg.RPCPass,
DisableTLS: cfg.DisableTLS,
}
if !cfg.DisableTLS {
certificate, err := ioutil.ReadFile(cfg.RPCCert)
if err != nil {
return nil, err
}
server.rpcConnConfig.Certificates = certificate
}
return &server, nil
}
func (s *server) start() error {
log.Printf("Connecting RPC client to %s", s.cfg.Host)
rpcClient, err := rpcclient.New(s.rpcConnConfig, nil)
if err != nil {
return errors.New(fmt.Sprintf("failed to create RPC client: %s", err))
}
s.rpcClient = rpcClient
log.Printf("Starting server on port %d", s.cfg.ListenPort)
handler := http.NewServeMux()
handler.HandleFunc("/", s.handleRequest)
s.httpServer = &http.Server{
Addr: fmt.Sprintf(":%d", s.cfg.ListenPort),
Handler: handler,
}
return s.httpServer.ListenAndServe()
}
func (s *server) handleRequest(responseWriter http.ResponseWriter, request *http.Request) {
s.allowCrossOrigin(responseWriter)
if request.Method == "OPTIONS" {
// OPTIONS must stop here or else CORS protection will throw a tantrum.
return
}
if request.Method != "POST" {
responseWriter.WriteHeader(404)
return
}
forwardedResponse, err := s.forwardRequest(request)
if err != nil {
responseWriter.WriteHeader(500)
log.Printf("failed to forward request: %s", err)
return
}
_, err = responseWriter.Write([]byte(forwardedResponse))
if err != nil {
responseWriter.WriteHeader(500)
log.Printf("failed to write response: %s", err)
return
}
}
func (s *server) allowCrossOrigin(responseWriter http.ResponseWriter) {
responseWriter.Header().Set("Access-Control-Allow-Origin", "*")
responseWriter.Header().Set("Access-Control-Allow-Headers", "Accept, Content-Type, Content-Length, Accept-Encoding, X-CSRF-Token, Authorization")
responseWriter.Header().Set("Access-Control-Allow-Methods", "POST, GET, OPTIONS, PUT, DELETE")
}
func (s *server) forwardRequest(request *http.Request) ([]byte, error) {
jsonRPCMethod := strings.TrimPrefix(request.URL.Path, "/")
requestBody, err := ioutil.ReadAll(request.Body)
if err != nil {
return nil, errors.New(fmt.Sprintf("failed to read request body: %s", err))
}
var jsonRPCParams []json.RawMessage
err = json.Unmarshal(requestBody, &jsonRPCParams)
if err != nil {
return nil, errors.New(fmt.Sprintf("failed to parse params: %s", err))
}
response, err := s.rpcClient.RawRequest(jsonRPCMethod, jsonRPCParams)
if err != nil {
return nil, errors.New(fmt.Sprintf("request to rpc server failed: %s", err))
}
return response, nil
}
func (s *server) stop() error {
log.Printf("Disconnecting RPC client")
s.rpcClient.Disconnect()
log.Printf("Stopping server")
return s.httpServer.Close()
}