Files
hop-gate/cmd/client/main.go
dalbodeule 38f05db0dc [feat](client): add local HTTP proxying for gRPC-based tunnels
- Enhanced gRPC client with logic to forward incoming tunnel streams as HTTP requests to a local target.
- Implemented per-stream state management for matching StreamOpen/StreamData/StreamClose to HTTP requests/responses.
- Added mechanisms to assemble HTTP requests, send them locally, and respond via tunnel streams.
- Introduced a configurable HTTP client with proper headers and connection settings for robust forwarding.
2025-12-11 19:05:26 +09:00

796 lines
24 KiB
Go

package main
import (
"bytes"
"context"
"crypto/tls"
"crypto/x509"
"flag"
"fmt"
"io"
"net"
"net/http"
"net/url"
"os"
"strconv"
"strings"
"sync"
"time"
"google.golang.org/grpc"
"google.golang.org/grpc/credentials"
"github.com/dalbodeule/hop-gate/internal/config"
"github.com/dalbodeule/hop-gate/internal/logging"
"github.com/dalbodeule/hop-gate/internal/protocol"
protocolpb "github.com/dalbodeule/hop-gate/internal/protocol/pb"
)
// version 은 빌드 시 -ldflags "-X main.version=xxxxxxx" 로 덮어쓰이는 필드입니다.
// 기본값 "dev" 는 로컬 개발용입니다.
var version = "dev"
func getEnvOrPanic(logger logging.Logger, key string) string {
value, exists := os.LookupEnv(key)
if !exists || strings.TrimSpace(value) == "" {
logger.Error("missing required environment variable", logging.Fields{
"env": key,
})
os.Exit(1)
}
return value
}
// maskAPIKey 는 로그에 노출할 때 클라이언트 API Key 를 일부만 보여주기 위한 헬퍼입니다.
func maskAPIKey(key string) string {
if len(key) <= 8 {
return "***"
}
return key[:4] + "..." + key[len(key)-4:]
}
// firstNonEmpty 는 앞에서부터 처음으로 non-empty 인 문자열을 반환합니다.
func firstNonEmpty(values ...string) string {
for _, v := range values {
if strings.TrimSpace(v) != "" {
return v
}
}
return ""
}
// runGRPCTunnelClient 는 gRPC 기반 터널을 사용하는 실험적 클라이언트 진입점입니다. (ko)
// runGRPCTunnelClient is an experimental entrypoint for a gRPC-based tunnel client. (en)
func runGRPCTunnelClient(ctx context.Context, logger logging.Logger, finalCfg *config.ClientConfig) error {
// TLS 설정은 기존 DTLS 클라이언트와 동일한 정책을 사용합니다. (ko)
// TLS configuration mirrors the existing DTLS client policy. (en)
var tlsCfg *tls.Config
if finalCfg.Debug {
tlsCfg = &tls.Config{
InsecureSkipVerify: true,
MinVersion: tls.VersionTLS12,
}
} else {
rootCAs, err := x509.SystemCertPool()
if err != nil || rootCAs == nil {
rootCAs = x509.NewCertPool()
}
tlsCfg = &tls.Config{
RootCAs: rootCAs,
MinVersion: tls.VersionTLS12,
}
}
// finalCfg.ServerAddr 가 "host:port" 형태이므로, SNI 에는 DNS(host) 부분만 넣어야 한다.
host := finalCfg.ServerAddr
if h, _, err := net.SplitHostPort(finalCfg.ServerAddr); err == nil && strings.TrimSpace(h) != "" {
host = h
}
tlsCfg.ServerName = host
creds := credentials.NewTLS(tlsCfg)
log := logger.With(logging.Fields{
"component": "grpc_tunnel_client",
"server_addr": finalCfg.ServerAddr,
"domain": finalCfg.Domain,
"local_target": finalCfg.LocalTarget,
})
log.Info("dialing grpc tunnel", nil)
conn, err := grpc.DialContext(ctx, finalCfg.ServerAddr, grpc.WithTransportCredentials(creds), grpc.WithBlock())
if err != nil {
log.Error("failed to dial grpc tunnel server", logging.Fields{
"error": err.Error(),
})
return err
}
defer conn.Close()
client := protocolpb.NewHopGateTunnelClient(conn)
stream, err := client.OpenTunnel(ctx)
if err != nil {
log.Error("failed to open grpc tunnel stream", logging.Fields{
"error": err.Error(),
})
return err
}
log.Info("grpc tunnel stream opened", nil)
// 초기 핸드셰이크: 도메인, API 키, 로컬 타깃 정보를 StreamOpen 헤더로 전송합니다. (ko)
// Initial handshake: send domain, API key, and local target via StreamOpen headers. (en)
headers := map[string]*protocolpb.HeaderValues{
"X-HopGate-Domain": {Values: []string{finalCfg.Domain}},
"X-HopGate-API-Key": {Values: []string{finalCfg.ClientAPIKey}},
"X-HopGate-Local-Target": {Values: []string{finalCfg.LocalTarget}},
}
open := &protocolpb.StreamOpen{
Id: "control-0",
ServiceName: "control",
TargetAddr: "",
Header: headers,
}
env := &protocolpb.Envelope{
Payload: &protocolpb.Envelope_StreamOpen{
StreamOpen: open,
},
}
if err := stream.Send(env); err != nil {
log.Error("failed to send initial stream_open handshake", logging.Fields{
"error": err.Error(),
})
return err
}
log.Info("sent initial stream_open handshake on grpc tunnel", logging.Fields{
"domain": finalCfg.Domain,
"local_target": finalCfg.LocalTarget,
"api_key_mask": maskAPIKey(finalCfg.ClientAPIKey),
})
// 로컬 HTTP 프록시용 HTTP 클라이언트 구성. (ko)
// HTTP client used to forward requests to the local target. (en)
httpClient := &http.Client{
Timeout: 30 * time.Second,
Transport: &http.Transport{
Proxy: http.ProxyFromEnvironment,
DialContext: (&net.Dialer{
Timeout: 10 * time.Second,
KeepAlive: 30 * time.Second,
}).DialContext,
ForceAttemptHTTP2: true,
MaxIdleConns: 100,
IdleConnTimeout: 90 * time.Second,
TLSHandshakeTimeout: 10 * time.Second,
ExpectContinueTimeout: 1 * time.Second,
},
}
// 서버→클라이언트 방향 StreamOpen/StreamData/StreamClose 를
// HTTP 요청 단위로 모으기 위한 per-stream 상태 테이블입니다. (ko)
// Per-stream state table to assemble HTTP requests from StreamOpen/Data/Close. (en)
type inboundStream struct {
open *protocolpb.StreamOpen
body bytes.Buffer
}
streams := make(map[string]*inboundStream)
var streamsMu sync.Mutex
// gRPC 스트림에 대한 Send 는 동시 호출이 안전하지 않으므로, sendMu 로 직렬화합니다. (ko)
// gRPC streaming Send is not safe for concurrent calls; protect with a mutex. (en)
var sendMu sync.Mutex
sendEnv := func(e *protocolpb.Envelope) error {
sendMu.Lock()
defer sendMu.Unlock()
return stream.Send(e)
}
// 서버에서 전달된 StreamOpen/StreamData/StreamClose 를 로컬 HTTP 요청으로 변환하고,
// 응답을 StreamOpen/StreamData/StreamClose 로 다시 서버에 전송하는 헬퍼입니다. (ko)
// handleStream forwards a single logical HTTP request to the local target
// and sends the response back as StreamOpen/StreamData/StreamClose frames. (en)
handleStream := func(so *protocolpb.StreamOpen, body []byte) {
go func() {
streamID := strings.TrimSpace(so.Id)
if streamID == "" {
log.Error("inbound stream has empty id", logging.Fields{})
return
}
if finalCfg.LocalTarget == "" {
log.Error("local target is empty; cannot forward request", logging.Fields{
"stream_id": streamID,
})
return
}
// Pseudo-headers 에서 메서드/URL/Host 추출. (ko)
// Extract method/URL/host from pseudo-headers. (en)
method := http.MethodGet
if hv, ok := so.Header[protocol.HeaderKeyMethod]; ok && hv != nil && len(hv.Values) > 0 && strings.TrimSpace(hv.Values[0]) != "" {
method = hv.Values[0]
}
urlStr := "/"
if hv, ok := so.Header[protocol.HeaderKeyURL]; ok && hv != nil && len(hv.Values) > 0 && strings.TrimSpace(hv.Values[0]) != "" {
urlStr = hv.Values[0]
}
u, err := url.Parse(urlStr)
if err != nil {
errMsg := fmt.Sprintf("parse url from stream_open: %v", err)
log.Error("failed to parse url from stream_open", logging.Fields{
"stream_id": streamID,
"error": err.Error(),
})
respHeader := map[string]*protocolpb.HeaderValues{
"Content-Type": {
Values: []string{"text/plain; charset=utf-8"},
},
protocol.HeaderKeyStatus: {
Values: []string{strconv.Itoa(http.StatusBadGateway)},
},
}
respOpen := &protocolpb.Envelope{
Payload: &protocolpb.Envelope_StreamOpen{
StreamOpen: &protocolpb.StreamOpen{
Id: streamID,
ServiceName: so.ServiceName,
TargetAddr: so.TargetAddr,
Header: respHeader,
},
},
}
if err2 := sendEnv(respOpen); err2 != nil {
log.Error("failed to send error stream_open from client", logging.Fields{
"stream_id": streamID,
"error": err2.Error(),
})
return
}
dataEnv := &protocolpb.Envelope{
Payload: &protocolpb.Envelope_StreamData{
StreamData: &protocolpb.StreamData{
Id: streamID,
Seq: 0,
Data: []byte("HopGate client: " + errMsg),
},
},
}
if err2 := sendEnv(dataEnv); err2 != nil {
log.Error("failed to send error stream_data from client", logging.Fields{
"stream_id": streamID,
"error": err2.Error(),
})
return
}
closeEnv := &protocolpb.Envelope{
Payload: &protocolpb.Envelope_StreamClose{
StreamClose: &protocolpb.StreamClose{
Id: streamID,
Error: errMsg,
},
},
}
if err2 := sendEnv(closeEnv); err2 != nil {
log.Error("failed to send error stream_close from client", logging.Fields{
"stream_id": streamID,
"error": err2.Error(),
})
}
return
}
u.Scheme = "http"
u.Host = finalCfg.LocalTarget
// 로컬 HTTP 요청용 헤더 구성 (pseudo-headers 제거). (ko)
// Build local HTTP headers, stripping pseudo-headers. (en)
httpHeader := make(http.Header, len(so.Header))
for k, hv := range so.Header {
if k == protocol.HeaderKeyMethod ||
k == protocol.HeaderKeyURL ||
k == protocol.HeaderKeyHost ||
k == protocol.HeaderKeyStatus {
continue
}
if hv == nil {
continue
}
for _, v := range hv.Values {
httpHeader.Add(k, v)
}
}
var reqBody io.Reader
if len(body) > 0 {
reqBody = bytes.NewReader(body)
}
req, err := http.NewRequestWithContext(ctx, method, u.String(), reqBody)
if err != nil {
errMsg := fmt.Sprintf("create http request from stream: %v", err)
log.Error("failed to create local http request", logging.Fields{
"stream_id": streamID,
"error": err.Error(),
})
respHeader := map[string]*protocolpb.HeaderValues{
"Content-Type": {
Values: []string{"text/plain; charset=utf-8"},
},
protocol.HeaderKeyStatus: {
Values: []string{strconv.Itoa(http.StatusBadGateway)},
},
}
respOpen := &protocolpb.Envelope{
Payload: &protocolpb.Envelope_StreamOpen{
StreamOpen: &protocolpb.StreamOpen{
Id: streamID,
ServiceName: so.ServiceName,
TargetAddr: so.TargetAddr,
Header: respHeader,
},
},
}
if err2 := sendEnv(respOpen); err2 != nil {
log.Error("failed to send error stream_open from client", logging.Fields{
"stream_id": streamID,
"error": err2.Error(),
})
return
}
dataEnv := &protocolpb.Envelope{
Payload: &protocolpb.Envelope_StreamData{
StreamData: &protocolpb.StreamData{
Id: streamID,
Seq: 0,
Data: []byte("HopGate client: " + errMsg),
},
},
}
if err2 := sendEnv(dataEnv); err2 != nil {
log.Error("failed to send error stream_data from client", logging.Fields{
"stream_id": streamID,
"error": err2.Error(),
})
return
}
closeEnv := &protocolpb.Envelope{
Payload: &protocolpb.Envelope_StreamClose{
StreamClose: &protocolpb.StreamClose{
Id: streamID,
Error: errMsg,
},
},
}
if err2 := sendEnv(closeEnv); err2 != nil {
log.Error("failed to send error stream_close from client", logging.Fields{
"stream_id": streamID,
"error": err2.Error(),
})
}
return
}
req.Header = httpHeader
if len(body) > 0 {
req.ContentLength = int64(len(body))
}
start := time.Now()
logReq := log.With(logging.Fields{
"component": "grpc_client_proxy",
"stream_id": streamID,
"service": so.ServiceName,
"method": method,
"url": urlStr,
"local_target": finalCfg.LocalTarget,
})
logReq.Info("forwarding stream http request to local target", nil)
res, err := httpClient.Do(req)
if err != nil {
errMsg := fmt.Sprintf("perform local http request: %v", err)
logReq.Error("local http request failed", logging.Fields{
"error": err.Error(),
})
respHeader := map[string]*protocolpb.HeaderValues{
"Content-Type": {
Values: []string{"text/plain; charset=utf-8"},
},
protocol.HeaderKeyStatus: {
Values: []string{strconv.Itoa(http.StatusBadGateway)},
},
}
respOpen := &protocolpb.Envelope{
Payload: &protocolpb.Envelope_StreamOpen{
StreamOpen: &protocolpb.StreamOpen{
Id: streamID,
ServiceName: so.ServiceName,
TargetAddr: so.TargetAddr,
Header: respHeader,
},
},
}
if err2 := sendEnv(respOpen); err2 != nil {
logReq.Error("failed to send error stream_open from client", logging.Fields{
"error": err2.Error(),
})
return
}
dataEnv := &protocolpb.Envelope{
Payload: &protocolpb.Envelope_StreamData{
StreamData: &protocolpb.StreamData{
Id: streamID,
Seq: 0,
Data: []byte("HopGate client: " + errMsg),
},
},
}
if err2 := sendEnv(dataEnv); err2 != nil {
logReq.Error("failed to send error stream_data from client", logging.Fields{
"error": err2.Error(),
})
return
}
closeEnv := &protocolpb.Envelope{
Payload: &protocolpb.Envelope_StreamClose{
StreamClose: &protocolpb.StreamClose{
Id: streamID,
Error: errMsg,
},
},
}
if err2 := sendEnv(closeEnv); err2 != nil {
logReq.Error("failed to send error stream_close from client", logging.Fields{
"error": err2.Error(),
})
}
return
}
defer res.Body.Close()
// 응답 헤더 맵을 복사하고 상태 코드를 pseudo-header 로 추가합니다. (ko)
// Copy response headers and attach status code as a pseudo-header. (en)
respHeader := make(map[string]*protocolpb.HeaderValues, len(res.Header)+1)
for k, vs := range res.Header {
hv := &protocolpb.HeaderValues{
Values: append([]string(nil), vs...),
}
respHeader[k] = hv
}
statusCode := res.StatusCode
if statusCode == 0 {
statusCode = http.StatusOK
}
respHeader[protocol.HeaderKeyStatus] = &protocolpb.HeaderValues{
Values: []string{strconv.Itoa(statusCode)},
}
respOpen := &protocolpb.Envelope{
Payload: &protocolpb.Envelope_StreamOpen{
StreamOpen: &protocolpb.StreamOpen{
Id: streamID,
ServiceName: so.ServiceName,
TargetAddr: so.TargetAddr,
Header: respHeader,
},
},
}
if err := sendEnv(respOpen); err != nil {
logReq.Error("failed to send stream response open envelope from client", logging.Fields{
"error": err.Error(),
})
return
}
// 응답 바디를 4KiB(StreamChunkSize) 단위로 잘라 StreamData 프레임으로 전송합니다. (ko)
// Chunk the response body into 4KiB (StreamChunkSize) StreamData frames. (en)
buf := make([]byte, protocol.StreamChunkSize)
var seq uint64
for {
n, err := res.Body.Read(buf)
if n > 0 {
dataCopy := append([]byte(nil), buf[:n]...)
dataEnv := &protocolpb.Envelope{
Payload: &protocolpb.Envelope_StreamData{
StreamData: &protocolpb.StreamData{
Id: streamID,
Seq: seq,
Data: dataCopy,
},
},
}
if err2 := sendEnv(dataEnv); err2 != nil {
logReq.Error("failed to send stream response data envelope from client", logging.Fields{
"error": err2.Error(),
})
return
}
seq++
}
if err == io.EOF {
break
}
if err != nil {
logReq.Error("failed to read local http response body", logging.Fields{
"error": err.Error(),
})
break
}
}
closeEnv := &protocolpb.Envelope{
Payload: &protocolpb.Envelope_StreamClose{
StreamClose: &protocolpb.StreamClose{
Id: streamID,
Error: "",
},
},
}
if err := sendEnv(closeEnv); err != nil {
logReq.Error("failed to send stream response close envelope from client", logging.Fields{
"error": err.Error(),
})
return
}
logReq.Info("stream http response sent from client", logging.Fields{
"status": statusCode,
"elapsed_ms": time.Since(start).Milliseconds(),
"error": "",
})
}()
}
// 수신 루프: 서버에서 들어오는 StreamOpen/StreamData/StreamClose 를
// 로컬 HTTP 요청으로 변환하고 응답을 다시 터널로 전송합니다. (ko)
// Receive loop: convert incoming StreamOpen/StreamData/StreamClose into local
// HTTP requests and send responses back over the tunnel. (en)
for {
if ctx.Err() != nil {
log.Info("context cancelled, closing grpc tunnel client", logging.Fields{
"error": ctx.Err().Error(),
})
return ctx.Err()
}
in, err := stream.Recv()
if err != nil {
if err == io.EOF {
log.Info("grpc tunnel stream closed by server", nil)
return nil
}
log.Error("grpc tunnel receive error", logging.Fields{
"error": err.Error(),
})
return err
}
payloadType := "unknown"
switch payload := in.Payload.(type) {
case *protocolpb.Envelope_HttpRequest:
payloadType = "http_request"
case *protocolpb.Envelope_HttpResponse:
payloadType = "http_response"
case *protocolpb.Envelope_StreamOpen:
payloadType = "stream_open"
so := payload.StreamOpen
if so == nil {
log.Error("received stream_open with nil payload on grpc tunnel client", logging.Fields{})
continue
}
streamID := strings.TrimSpace(so.Id)
if streamID == "" {
log.Error("received stream_open with empty stream id on grpc tunnel client", logging.Fields{})
continue
}
streamsMu.Lock()
if _, exists := streams[streamID]; exists {
log.Error("received duplicate stream_open for existing stream on grpc tunnel client", logging.Fields{
"stream_id": streamID,
})
streamsMu.Unlock()
continue
}
streams[streamID] = &inboundStream{open: so}
streamsMu.Unlock()
case *protocolpb.Envelope_StreamData:
payloadType = "stream_data"
sd := payload.StreamData
if sd == nil {
log.Error("received stream_data with nil payload on grpc tunnel client", logging.Fields{})
continue
}
streamID := strings.TrimSpace(sd.Id)
if streamID == "" {
log.Error("received stream_data with empty stream id on grpc tunnel client", logging.Fields{})
continue
}
streamsMu.Lock()
st := streams[streamID]
streamsMu.Unlock()
if st == nil {
log.Warn("received stream_data for unknown stream on grpc tunnel client", logging.Fields{
"stream_id": streamID,
})
continue
}
if len(sd.Data) > 0 {
if _, err := st.body.Write(sd.Data); err != nil {
log.Error("failed to buffer stream_data body on grpc tunnel client", logging.Fields{
"stream_id": streamID,
"error": err.Error(),
})
}
}
case *protocolpb.Envelope_StreamClose:
payloadType = "stream_close"
sc := payload.StreamClose
if sc == nil {
log.Error("received stream_close with nil payload on grpc tunnel client", logging.Fields{})
continue
}
streamID := strings.TrimSpace(sc.Id)
if streamID == "" {
log.Error("received stream_close with empty stream id on grpc tunnel client", logging.Fields{})
continue
}
streamsMu.Lock()
st := streams[streamID]
if st != nil {
delete(streams, streamID)
}
streamsMu.Unlock()
if st == nil {
log.Warn("received stream_close for unknown stream on grpc tunnel client", logging.Fields{
"stream_id": streamID,
})
continue
}
// 현재까지 수신한 메타데이터/바디를 사용해 로컬 HTTP 요청을 수행하고,
// 응답을 다시 터널로 전송합니다. (ko)
// Use the accumulated metadata/body to perform the local HTTP request and
// send the response back over the tunnel. (en)
bodyCopy := append([]byte(nil), st.body.Bytes()...)
handleStream(st.open, bodyCopy)
case *protocolpb.Envelope_StreamAck:
payloadType = "stream_ack"
// 현재 gRPC 터널에서는 StreamAck 를 사용하지 않습니다. (ko)
// StreamAck is currently unused for gRPC tunnels. (en)
default:
payloadType = fmt.Sprintf("unknown(%T)", in.Payload)
}
log.Info("received envelope on grpc tunnel client", logging.Fields{
"payload_type": payloadType,
})
}
}
func main() {
logger := logging.NewStdJSONLogger("client")
// 1. 환경변수(.env 포함)에서 클라이언트 설정 로드
// internal/config 패키지가 .env 를 먼저 읽고, 이미 설정된 OS 환경변수를 우선시합니다.
envCfg, err := config.LoadClientConfigFromEnv()
if err != nil {
logger.Error("failed to load client config from env", logging.Fields{
"error": err.Error(),
})
os.Exit(1)
}
// 2. 필수 환경 변수 유효성 검사 (.env 포함; OS 환경변수가 우선)
serverAddrEnv := getEnvOrPanic(logger, "HOP_CLIENT_SERVER_ADDR")
clientDomainEnv := getEnvOrPanic(logger, "HOP_CLIENT_DOMAIN")
apiKeyEnv := getEnvOrPanic(logger, "HOP_CLIENT_API_KEY")
localTargetEnv := getEnvOrPanic(logger, "HOP_CLIENT_LOCAL_TARGET")
debugEnv := getEnvOrPanic(logger, "HOP_CLIENT_DEBUG")
// 디버깅 플래그 형식 확인
if debugEnv != "true" && debugEnv != "false" {
logger.Error("invalid value for HOP_CLIENT_DEBUG; must be 'true' or 'false'", logging.Fields{
"env": "HOP_CLIENT_DEBUG",
"value": debugEnv,
})
os.Exit(1)
}
// 유효성 검사 결과를 구조화 로그로 출력
logger.Info("validated client env vars", logging.Fields{
"HOP_CLIENT_SERVER_ADDR": serverAddrEnv,
"HOP_CLIENT_DOMAIN": clientDomainEnv,
"HOP_CLIENT_API_KEY_MASK": maskAPIKey(apiKeyEnv),
"HOP_CLIENT_LOCAL_TARGET": localTargetEnv,
"HOP_CLIENT_DEBUG": debugEnv,
})
// CLI 인자 정의 (env 보다 우선 적용됨)
serverAddrFlag := flag.String("server-addr", "", "HopGate server address (host:port)")
domainFlag := flag.String("domain", "", "registered domain (e.g. api.example.com)")
apiKeyFlag := flag.String("api-key", "", "client API key for the domain (64 chars)")
localTargetFlag := flag.String("local-target", "", "local HTTP target (host:port), e.g. 127.0.0.1:8080")
flag.Parse()
// 2. CLI 인자 우선, env 후순위로 최종 설정 구성
finalCfg := &config.ClientConfig{
ServerAddr: firstNonEmpty(strings.TrimSpace(*serverAddrFlag), strings.TrimSpace(envCfg.ServerAddr)),
Domain: firstNonEmpty(strings.TrimSpace(*domainFlag), strings.TrimSpace(envCfg.Domain)),
ClientAPIKey: firstNonEmpty(strings.TrimSpace(*apiKeyFlag), strings.TrimSpace(envCfg.ClientAPIKey)),
LocalTarget: firstNonEmpty(strings.TrimSpace(*localTargetFlag), strings.TrimSpace(envCfg.LocalTarget)),
Debug: envCfg.Debug,
Logging: envCfg.Logging,
}
// 3. 필수 필드 검증
missing := []string{}
if finalCfg.ServerAddr == "" {
missing = append(missing, "server_addr")
}
if finalCfg.Domain == "" {
missing = append(missing, "domain")
}
if finalCfg.ClientAPIKey == "" {
missing = append(missing, "api_key")
}
if finalCfg.LocalTarget == "" {
missing = append(missing, "local_target")
}
if len(missing) > 0 {
logger.Error("client config missing required fields", logging.Fields{
"missing": missing,
})
os.Exit(1)
}
logger.Info("hop-gate client starting", logging.Fields{
"stack": "prometheus-loki-grafana",
"version": version,
"server_addr": finalCfg.ServerAddr,
"domain": finalCfg.Domain,
"local_target": finalCfg.LocalTarget,
"client_api_key_masked": maskAPIKey(finalCfg.ClientAPIKey),
"debug": finalCfg.Debug,
})
ctx := context.Background()
// 현재 클라이언트는 DTLS 레이어 없이 gRPC 터널만을 사용합니다. (ko)
// The client now uses only the gRPC tunnel, without any DTLS layer. (en)
if err := runGRPCTunnelClient(ctx, logger, finalCfg); err != nil {
logger.Error("grpc tunnel client exited with error", logging.Fields{
"error": err.Error(),
})
os.Exit(1)
}
logger.Info("grpc tunnel client exited normally", nil)
}