feat(api): add hostEndpoint in /info (#103)

Signed-off-by: Kevin Cui <bh@bugs.cc>

Author: BlackHole1

pkg/ipc/restful/run.go

@@ -75,14 +75,23 @@ func (r *routerRun) mux() http.Handler {
 }
 
 type infoResponse struct {
-	PodmanHost string `json:"podmanHost"`
-	PodmanPort int    `json:"podmanPort"`
+	PodmanHost   string `json:"podmanHost"`
+	PodmanPort   int    `json:"podmanPort"`
+	HostEndpoint string `json:"hostEndpoint"`
 }
 
 func (r *routerRun) info(w http.ResponseWriter, req *http.Request) {
+	he, err := wsl.HostEndpoint(r.log, r.opt.DistroName)
+	if err != nil {
+		r.log.Warnf("Failed to get host endpoint: %v", err)
+		http.Error(w, "failed to get host endpoint", http.StatusInternalServerError)
+		return
+	}
+
 	_ = json.NewEncoder(w).Encode(&infoResponse{
-		PodmanHost: "127.0.0.1",
-		PodmanPort: r.opt.PodmanPort,
+		PodmanHost:   "127.0.0.1",
+		PodmanPort:   r.opt.PodmanPort,
+		HostEndpoint: he,
 	})
 }
 

pkg/wsl/config.go

@@ -25,7 +25,8 @@ func NewConfig(log *logger.Context) *Config {
 }
 
 func (c *Config) ExistIncompatible() bool {
-	return c.findKey("wsl2", "kernel")
+	_, ok := c.GetValue("wsl2", "kernel")
+	return ok
 }
 
 func (c *Config) Fix() error {
@@ -56,17 +57,17 @@ func (c *Config) Open() error {
 	return nil
 }
 
-func (c *Config) findKey(expectSection string, expectKey string) bool {
+func (c *Config) GetValue(expectSection string, expectKey string) (string, bool) {
 	wslConfigPath, ok := c.path()
 	if !ok {
 		c.log.Info("WSL config file not found")
-		return false
+		return "", false
 	}
 
 	file, err := os.Open(wslConfigPath)
 	if err != nil {
 		c.log.Warnf("Failed to open .wslconfig file: %v", err)
-		return false
+		return "", false
 	}
 	defer file.Close()
 
@@ -107,16 +108,16 @@ func (c *Config) findKey(expectSection string, expectKey string) bool {
 		}
 
 		c.log.Infof("Find %s key in .wslconfig: %s", expectKey, line)
-		return true
+		return val, true
 	}
 
 	if err := scanner.Err(); err != nil {
 		c.log.Warnf("Failed to scan .wslconfig: %v", err)
-		return false
+		return "", false
 	}
 
 	c.log.Infof("No %s key config found in WSL config file: %s", expectKey, wslConfigPath)
-	return false
+	return "", false
 }
 
 func (c *Config) commentKey(expectKey string) error {

pkg/wsl/host.go

@@ -0,0 +1,63 @@
+// SPDX-FileCopyrightText: 2025 OOMOL, Inc. <https://www.oomol.com>
+// SPDX-License-Identifier: MPL-2.0
+
+package wsl
+
+import (
+	"bytes"
+	"fmt"
+	"strings"
+
+	"github.com/oomol-lab/ovm-win/pkg/logger"
+	"github.com/oomol-lab/ovm-win/pkg/util"
+)
+
+var (
+	_hostEndpoint string
+)
+
+func HostEndpoint(log *logger.Context, name string) (string, error) {
+	// TODO(@BlackHole1): getHostEndpoint may be slow, so it needs to be thread-safe here
+	if _hostEndpoint != "" {
+		return _hostEndpoint, nil
+	}
+
+	if he, err := getHostEndpoint(log, name); err != nil {
+		return "", fmt.Errorf("failed to get host endpoint: %w", err)
+	} else {
+		_hostEndpoint = he
+	}
+
+	log.Infof("Host endpoint is: %s", _hostEndpoint)
+
+	return _hostEndpoint, nil
+}
+
+func isMirroredNetwork(log *logger.Context) bool {
+	val, _ := NewConfig(log).GetValue("wsl2", "networkingMode")
+	return val == "mirrored"
+}
+
+func getHostEndpoint(log *logger.Context, name string) (string, error) {
+	if isMirroredNetwork(log) {
+		return "localhost", nil
+	}
+
+	// TODO(@BlackHole1): improve wslInvoke
+	newArgs := []string{"-d", name, "/bin/sh", "-c", "ip route  | grep '^default' | awk '{print $3}'"}
+	cmd := util.SilentCmd(Find(), newArgs...)
+	var stdout bytes.Buffer
+	var stderr bytes.Buffer
+	cmd.Stdout = &stdout
+	cmd.Stderr = &stderr
+	cmd.Env = []string{"WSL_UTF8=1"}
+
+	cmdStr := fmt.Sprintf("%s %s", Find(), strings.Join(newArgs, " "))
+
+	log.Infof("Running command in distro: %s", cmdStr)
+	if err := cmd.Run(); err != nil {
+		return "", fmt.Errorf("failed to run command in distro: %w, %s", err, stderr.String())
+	}
+
+	return strings.TrimSpace(stdout.String()), nil
+}