feat: rules hot reload via SIGHUP (#44)

cmd/root.go

@@ -7,6 +7,7 @@ import (
 	"os/signal"
 	"strconv"
 	"strings"
+	"syscall"
 
 	"github.com/apernet/OpenGFW/analyzer"
 	"github.com/apernet/OpenGFW/analyzer/tcp"
@@ -267,14 +268,42 @@ func runMain(cmd *cobra.Command, args []string) {
 		logger.Fatal("failed to initialize engine", zap.Error(err))
 	}
 
+	// Signal handling
 	ctx, cancelFunc := context.WithCancel(context.Background())
 	go func() {
-		sigChan := make(chan os.Signal)
-		signal.Notify(sigChan, os.Interrupt, os.Kill)
-		<-sigChan
+		// Graceful shutdown
+		shutdownChan := make(chan os.Signal)
+		signal.Notify(shutdownChan, os.Interrupt, os.Kill)
+		<-shutdownChan
 		logger.Info("shutting down gracefully...")
 		cancelFunc()
 	}()
+	go func() {
+		// Rule reload
+		reloadChan := make(chan os.Signal)
+		signal.Notify(reloadChan, syscall.SIGHUP)
+		for {
+			<-reloadChan
+			logger.Info("reloading rules")
+			rawRs, err := ruleset.ExprRulesFromYAML(args[0])
+			if err != nil {
+				logger.Error("failed to load rules, using old rules", zap.Error(err))
+				continue
+			}
+			rs, err := ruleset.CompileExprRules(rawRs, analyzers, modifiers, rsConfig)
+			if err != nil {
+				logger.Error("failed to compile rules, using old rules", zap.Error(err))
+				continue
+			}
+			err = en.UpdateRuleset(rs)
+			if err != nil {
+				logger.Error("failed to update ruleset", zap.Error(err))
+			} else {
+				logger.Info("rules reloaded")
+			}
+		}
+	}()
+
 	logger.Info("engine started")
 	logger.Info("engine exited", zap.Error(en.Run(ctx)))
 }