feat(rules): add protocol matching functionality

- Introduced a new checker for HTTP protocols (http, https, h3) in the routing rules.
- Added corresponding test cases to validate protocol matching behavior in requests.

internal/route/rules/on.go

@@ -31,6 +31,7 @@ const (
 	OnCookie    = "cookie"
 	OnForm      = "form"
 	OnPostForm  = "postform"
+	OnProto     = "proto"
 	OnMethod    = "method"
 	OnHost      = "host"
 	OnPath      = "path"
@@ -226,6 +227,41 @@ var checkers = map[string]struct {
 			}
 		},
 	},
+	OnProto: {
+		help: Help{
+			command: OnProto,
+			args: map[string]string{
+				"proto": "the http protocol (http, https, h3)",
+			},
+		},
+		validate: func(args []string) (any, gperr.Error) {
+			if len(args) != 1 {
+				return nil, ErrExpectOneArg
+			}
+			proto := args[0]
+			if proto != "http" && proto != "https" && proto != "h3" {
+				return nil, ErrInvalidArguments.Withf("proto: %q", proto)
+			}
+			return proto, nil
+		},
+		builder: func(args any) CheckFunc {
+			proto := args.(string)
+			switch proto {
+			case "http":
+				return func(w http.ResponseWriter, r *http.Request) bool {
+					return r.TLS == nil
+				}
+			case "https":
+				return func(w http.ResponseWriter, r *http.Request) bool {
+					return r.TLS != nil
+				}
+			default: // h3
+				return func(w http.ResponseWriter, r *http.Request) bool {
+					return r.TLS != nil && r.ProtoMajor == 3
+				}
+			}
+		},
+	},
 	OnMethod: {
 		help: Help{
 			command: OnMethod,

internal/route/rules/on_test.go

@@ -1,6 +1,7 @@
 package rules_test
 
 import (
+	"crypto/tls"
 	"encoding/base64"
 	"fmt"
 	"net/http"
@@ -65,6 +66,30 @@ func genCorrectnessTestCases(field string, genRequest func(k, v string) *http.Re
 
 func TestOnCorrectness(t *testing.T) {
 	tests := []testCorrectness{
+		{
+			name:    "proto_match_http",
+			checker: "proto http",
+			input:   &http.Request{TLS: nil},
+			want:    true,
+		},
+		{
+			name:    "proto_match_https",
+			checker: "proto https",
+			input:   &http.Request{TLS: &tls.ConnectionState{}},
+			want:    true,
+		},
+		{
+			name:    "proto_match_h3",
+			checker: "proto h3",
+			input:   &http.Request{TLS: &tls.ConnectionState{}, ProtoMajor: 3},
+			want:    true,
+		},
+		{
+			name:    "proto_no_match_h3",
+			checker: "proto h3",
+			input:   &http.Request{TLS: &tls.ConnectionState{}, ProtoMajor: 2},
+			want:    false,
+		},
 		{
 			name:    "method_match",
 			checker: "method GET",