feat: add browser argument builder and discovery

2026-07-22 14:55:35 +08:00
parent a5260496f3
commit cf828aec21
6 changed files with 285 additions and 3 deletions
@@ -0,0 +1,154 @@
+package browser
+
+import (
+	"context"
+	"errors"
+	"fmt"
+	"io/fs"
+	"net"
+	"net/url"
+	"os"
+	"path/filepath"
+	"strconv"
+	"strings"
+
+	"chub/internal/domain"
+)
+
+var (
+	ErrExecutableNotFound = errors.New("browser executable was not found")
+	ErrUnsafeArgument     = errors.New("browser argument is controlled or unsafe")
+)
+
+type Discoverer struct {
+	getenv func(string) string
+	stat   func(string) (fs.FileInfo, error)
+}
+
+func NewDiscoverer() *Discoverer { return &Discoverer{getenv: os.Getenv, stat: os.Stat} }
+
+func (d *Discoverer) Resolve(ctx context.Context, kind domain.BrowserKind, configured string) (string, error) {
+	if err := ctx.Err(); err != nil {
+		return "", err
+	}
+	if d == nil || d.getenv == nil || d.stat == nil || !kind.Valid() {
+		return "", ErrExecutableNotFound
+	}
+	if configured = strings.TrimSpace(configured); configured != "" {
+		if path, ok := d.executable(configured); ok {
+			return path, nil
+		}
+		return "", fmt.Errorf("%w: configured path is unavailable", ErrExecutableNotFound)
+	}
+	seen := make(map[string]struct{})
+	for _, candidate := range d.candidates(kind) {
+		cleaned := filepath.Clean(candidate)
+		key := strings.ToLower(cleaned)
+		if candidate == "" {
+			continue
+		}
+		if _, exists := seen[key]; exists {
+			continue
+		}
+		seen[key] = struct{}{}
+		if path, ok := d.executable(cleaned); ok {
+			return path, nil
+		}
+	}
+	return "", ErrExecutableNotFound
+}
+
+func (d *Discoverer) candidates(kind domain.BrowserKind) []string {
+	var suffixes []string
+	switch kind {
+	case domain.BrowserChrome:
+		suffixes = []string{`Google\Chrome\Application\chrome.exe`}
+	case domain.BrowserEdge:
+		suffixes = []string{`Microsoft\Edge\Application\msedge.exe`}
+	}
+	var candidates []string
+	for _, root := range []string{"PROGRAMFILES", "PROGRAMFILES(X86)", "LOCALAPPDATA"} {
+		for _, suffix := range suffixes {
+			candidates = append(candidates, filepath.Join(d.getenv(root), suffix))
+		}
+	}
+	return candidates
+}
+
+func (d *Discoverer) executable(path string) (string, bool) {
+	cleaned := filepath.Clean(strings.TrimSpace(path))
+	if cleaned == "." || !filepath.IsAbs(cleaned) {
+		return "", false
+	}
+	info, err := d.stat(cleaned)
+	if err != nil || info.IsDir() || !info.Mode().IsRegular() {
+		return "", false
+	}
+	return cleaned, true
+}
+
+func BuildArgs(spec domain.LaunchSpec) ([]string, error) {
+	normalized, err := spec.Normalize()
+	if err != nil {
+		return nil, err
+	}
+	proxy, err := normalizeProxy(normalized.ProxyServer)
+	if err != nil {
+		return nil, err
+	}
+	args := []string{
+		"--user-data-dir=" + normalized.UserDataDir,
+		"--no-first-run",
+		"--disable-default-apps",
+	}
+	if normalized.ProfileDirectory != "" {
+		args = append(args, "--profile-directory="+normalized.ProfileDirectory)
+	}
+	if normalized.Headless {
+		args = append(args, "--headless=new")
+	}
+	if proxy != "" {
+		args = append(args, "--proxy-server="+proxy)
+	}
+	for _, extra := range normalized.ExtraArgs {
+		if err := validateExtraArg(extra); err != nil {
+			return nil, err
+		}
+		args = append(args, extra)
+	}
+	return append(args, normalized.TargetURL), nil
+}
+
+func normalizeProxy(value string) (string, error) {
+	proxy := strings.TrimSpace(value)
+	if proxy == "" {
+		return "", nil
+	}
+	parsed, err := url.Parse(proxy)
+	if err != nil || parsed.User != nil || parsed.Hostname() == "" || parsed.Port() == "" || parsed.Path != "" || parsed.RawQuery != "" || parsed.Fragment != "" {
+		return "", fmt.Errorf("%w: proxy must be scheme://host:port without credentials", domain.ErrInvalidLaunchSpec)
+	}
+	scheme := strings.ToLower(parsed.Scheme)
+	if scheme != "http" && scheme != "https" && scheme != "socks4" && scheme != "socks5" {
+		return "", fmt.Errorf("%w: unsupported proxy scheme", domain.ErrInvalidLaunchSpec)
+	}
+	port, err := strconv.Atoi(parsed.Port())
+	if err != nil || port < 1 || port > 65535 {
+		return "", fmt.Errorf("%w: proxy port out of range", domain.ErrInvalidLaunchSpec)
+	}
+	return scheme + "://" + net.JoinHostPort(strings.ToLower(parsed.Hostname()), strconv.Itoa(port)), nil
+}
+
+func validateExtraArg(value string) error {
+	arg := strings.TrimSpace(value)
+	if arg == "" || !strings.HasPrefix(arg, "--") {
+		return fmt.Errorf("%w: extra arguments must be non-empty flags", ErrUnsafeArgument)
+	}
+	name := strings.ToLower(strings.SplitN(arg[2:], "=", 2)[0])
+	for _, controlled := range []string{"user-data-dir", "profile-directory", "proxy-server", "remote-debugging-address", "remote-debugging-port"} {
+		if name == controlled {
+			return fmt.Errorf("%w: --%s is controlled by LaunchSpec", ErrUnsafeArgument, controlled)
+		}
+	}
+	return nil
+}