Add hostname_port validator feature

baked_in.go

@@ -166,6 +166,7 @@ var (
 		"html_encoded":         isHTMLEncoded,
 		"url_encoded":          isURLEncoded,
 		"dir":                  isDir,
+		"hostname_port":        isHostnamePort,
 	}
 )
 
@@ -2007,3 +2008,22 @@ func isDir(fl FieldLevel) bool {
 
 	panic(fmt.Sprintf("Bad field type %T", field.Interface()))
 }
+
+// isHostnamePort validates a <dns>:<port> combination for fields typically used for socket address.
+func isHostnamePort(fl FieldLevel) bool {
+	val := fl.Field().String()
+	host, port, err := net.SplitHostPort(val)
+	if err != nil {
+		return false
+	}
+	// Port must be a iny <= 65535.
+	if portNum, err := strconv.ParseInt(port, 10, 32); err != nil || portNum > 65535 || portNum < 1 {
+		return false
+	}
+
+	// If host is specified, it should match a DNS name
+	if host != "" {
+		return hostnameRegexRFC1123.MatchString(host)
+	}
+	return true
+}

regexes.go

@@ -37,7 +37,7 @@ const (
 	longitudeRegexString             = "^[-+]?(180(\\.0+)?|((1[0-7]\\d)|([1-9]?\\d))(\\.\\d+)?)$"
 	sSNRegexString                   = `^[0-9]{3}[ -]?(0[1-9]|[1-9][0-9])[ -]?([1-9][0-9]{3}|[0-9][1-9][0-9]{2}|[0-9]{2}[1-9][0-9]|[0-9]{3}[1-9])$`
 	hostnameRegexStringRFC952        = `^[a-zA-Z][a-zA-Z0-9\-\.]+[a-zA-Z0-9]$`                                            // https://tools.ietf.org/html/rfc952
-	hostnameRegexStringRFC1123       = `^[a-zA-Z0-9][a-zA-Z0-9\-\.]+[a-zA-Z0-9]$` // accepts hostname starting with a digit https://tools.ietf.org/html/rfc1123
+	hostnameRegexStringRFC1123       = `^([a-zA-Z0-9]{1}[a-zA-Z0-9_-]{0,62}){1}(\.[a-zA-Z0-9_]{1}[a-zA-Z0-9_-]{0,62})*?$` // accepts hostname starting with a digit https://tools.ietf.org/html/rfc1123
 	btcAddressRegexString            = `^[13][a-km-zA-HJ-NP-Z1-9]{25,34}$`                                                // bitcoin address
 	btcAddressUpperRegexStringBech32 = `^BC1[02-9AC-HJ-NP-Z]{7,76}$`                                                      // bitcoin bech32 address https://en.bitcoin.it/wiki/Bech32
 	btcAddressLowerRegexStringBech32 = `^bc1[02-9ac-hj-np-z]{7,76}$`                                                      // bitcoin bech32 address https://en.bitcoin.it/wiki/Bech32

validator_test.go

@@ -7954,15 +7954,15 @@ func TestHostnameRFC1123Validation(t *testing.T) {
 
 		if test.expected {
 			if !IsEqual(errs, nil) {
-				t.Fatalf("Index: %d hostname failed Error: %v", i, errs)
+				t.Fatalf("Hostname: %v failed Error: %v", test, errs)
 			}
 		} else {
 			if IsEqual(errs, nil) {
-				t.Fatalf("Index: %d hostname failed Error: %v", i, errs)
+				t.Fatalf("Hostname: %v failed Error: %v", test, errs)
 			} else {
 				val := getError(errs, "", "")
 				if val.Tag() != "hostname_rfc1123" {
-					t.Fatalf("Index: %d hostname failed Error: %v", i, errs)
+					t.Fatalf("Hostname: %v failed Error: %v", i, errs)
 				}
 			}
 		}
@@ -9003,3 +9003,34 @@ func TestGetTag(t *testing.T) {
 	Equal(t, errs, nil)
 	Equal(t, tag, "mytag")
 }
+
+func Test_hostnameport_validator(t *testing.T) {
+
+	type Host struct {
+		Addr string `validate:"hostname_port"`
+	}
+
+	type testInput struct {
+		data     string
+		expected bool
+	}
+	testData := []testInput{
+		{"bad..domain.name:234", false},
+		{"extra.dot.com.", false},
+		{"localhost:1234", true},
+		{"192.168.1.1:1234", true},
+		{":1234", true},
+		{"domain.com:1334", true},
+		{"this.domain.com:234", true},
+		{"domain:75000", false},
+		{"missing.port", false},
+	}
+	for _, td := range testData {
+		h := Host{Addr: td.data}
+		v := New()
+		err := v.Struct(h)
+		if td.expected != (err == nil) {
+			t.Fatalf("Test failed for data: %v Error: %v", td.data, err)
+		}
+	}
+}