MPH domian matcher: Support building & using cache directly (instead of building from geosite.dat when Xray starts) (#5505)

Like https://github.com/XTLS/Xray-core/pull/5488#issuecomment-3710995080

main/commands/all/buildmphcache.go

@@ -0,0 +1,52 @@
+package all
+
+import (
+	"os"
+
+	"github.com/xtls/xray-core/common/platform"
+	"github.com/xtls/xray-core/infra/conf/serial"
+	"github.com/xtls/xray-core/main/commands/base"
+)
+
+var cmdBuildMphCache = &base.Command{
+	UsageLine: `{{.Exec}} buildMphCache [-c config.json] [-o domain.cache]`,
+	Short:     `Build domain matcher cache`,
+	Long: `
+Build domain matcher cache from a configuration file.
+
+Example: {{.Exec}} buildMphCache -c config.json -o domain.cache
+`,
+}
+
+func init() {
+	cmdBuildMphCache.Run = executeBuildMphCache
+}
+
+var (
+	configPath = cmdBuildMphCache.Flag.String("c", "config.json", "Config file path")
+	outputPath = cmdBuildMphCache.Flag.String("o", "domain.cache", "Output cache file path")
+)
+
+func executeBuildMphCache(cmd *base.Command, args []string) {
+	cf, err := os.Open(*configPath)
+	if err != nil {
+		base.Fatalf("failed to open config file: %v", err)
+	}
+	defer cf.Close()
+
+	// prevent using existing cache
+	domainMatcherPath := platform.NewEnvFlag(platform.MphCachePath).GetValue(func() string { return "" })
+	if domainMatcherPath != "" {
+		os.Setenv("XRAY_MPH_CACHE", "")
+		defer os.Setenv("XRAY_MPH_CACHE", domainMatcherPath)
+	}
+
+	config, err := serial.DecodeJSONConfig(cf)
+	if err != nil {
+		base.Fatalf("failed to decode config file: %v", err)
+	}
+
+	if err := config.BuildMPHCache(outputPath); err != nil {
+		base.Fatalf("failed to build MPH cache: %v", err)
+	}
+}

main/commands/all/commands.go

@@ -19,5 +19,6 @@ func init() {
 		cmdMLDSA65,
 		cmdMLKEM768,
 		cmdVLESSEnc,
+		cmdBuildMphCache,
 	)
 }