fix(issue-4448): added another flavour of same function with tests

Signed-off-by: ivan katliarchuk <ivan.katliarchuk@gmail.com>

provider/aws/aws.go

@@ -416,6 +416,7 @@ func convertOctalToAscii(input string) string {
 		if input[i] == '\\' && i+3 < len(input) {
 			octalStr := input[i+1 : i+4]
 			if octal, err := strconv.ParseInt(octalStr, 8, 8); err == nil {
+				fmt.Println("string:", octalStr, " char:", byte(octal))
 				result.WriteByte(byte(octal))
 				i += 3 // Skip the next 3 characters (the octal code)
 			} else {
@@ -428,6 +429,59 @@ func convertOctalToAscii(input string) string {
 	return result.String()
 }
 
+var octalCharTable = map[string]byte{
+	"041": byte(33), // exclamation mark
+	"042": byte(34), // double quote
+	"043": byte(35), // # number sing
+	"044": byte(36), // $ dollar
+	"045": byte(37), // % percentage
+	"046": byte(38), // & ampersand
+	"047": byte(39), // single quote
+	"050": byte(40), // ( left parenthesis
+	"051": byte(41), // ) right parenthesis
+	"052": byte(42), // * asterisk
+	"053": byte(43), // + plus
+	"054": byte(44), // , comma
+	"057": byte(47), // / forward slash
+	"072": byte(58), // : colon
+	"073": byte(59), // ; semicolon
+	"074": byte(60), // < less than sign
+	"075": byte(61), // = equal
+	"076": byte(62), // > greater than sign
+	"077": byte(63), // question mark
+	"100": byte(64), // @ at symbol
+	"133": byte(91), // [ left square bracket
+	"134": byte(92), // ] right square bracket
+	"135": byte(93), // ^ caret
+	"136": byte(94), // _ underscore
+	"140": byte(96), // ` backtick
+	"173": byte(123), // { left curly brace
+	"174": byte(124), // | vertical baar
+	"175": byte(125), // } right curly brace
+	"176": byte(126), // tilda
+}
+
+func convertOctalToAsciiWithHashTable(input string) string {
+	if !containsOctalSequence(input) {
+		return input
+	}
+	var result strings.Builder
+	for i := 0; i < len(input); i++ {
+		if input[i] == '\\' && i+3 < len(input) {
+			octalStr := input[i+1 : i+4]
+			if char, ok := octalCharTable[octalStr]; ok {
+				result.WriteByte(char)
+				i += 3 // Skip the next 3 characters (the octal code)
+			} else {
+				result.WriteString(input[i : i+4]) // Keep the entire sequence if not found
+			}
+		} else {
+			result.WriteByte(input[i])
+		}
+	}
+	return result.String()
+}
+
 // validateDomainName checks if the domain name contains valid octal escape sequences.
 func containsOctalSequence(domain string) bool {
 	// Pattern to match valid octal escape sequences

provider/aws/aws_test.go

@@ -386,9 +386,9 @@ func TestAWSRecords(t *testing.T) {
 			ResourceRecords: []*route53.ResourceRecord{{Value: aws.String("1.2.3.4")}},
 		},
 		{
-			Name:            aws.String(specialCharactersEscape("escape-%!s(<nil>)-codes-alias.zone-2.ext-dns-test-2.teapot.zalan.do.")),
-			Type:            aws.String(route53.RRTypeA),
-			TTL:             aws.Int64(recordTTL),
+			Name: aws.String(specialCharactersEscape("escape-%!s(<nil>)-codes-alias.zone-2.ext-dns-test-2.teapot.zalan.do.")),
+			Type: aws.String(route53.RRTypeA),
+			TTL:  aws.Int64(recordTTL),
 			AliasTarget: &route53.AliasTarget{
 				DNSName:              aws.String("escape-codes.eu-central-1.elb.amazonaws.com."),
 				EvaluateTargetHealth: aws.Bool(false),
@@ -2084,3 +2084,37 @@ func TestRequiresDeleteCreate(t *testing.T) {
 	assert.False(t, provider.requiresDeleteCreate(oldSetIdentifier, oldSetIdentifier), "actual and expected endpoints don't match. %+v:%+v", oldSetIdentifier, oldSetIdentifier)
 	assert.True(t, provider.requiresDeleteCreate(oldSetIdentifier, newSetIdentifier), "actual and expected endpoints don't match. %+v:%+v", oldSetIdentifier, newSetIdentifier)
 }
+
+func TestConvertOctalToAscii(t *testing.T) {
+	tests := []struct {
+		name     string
+		input    string
+		expected string
+	}{
+		{
+			name:     "Characters escaped !\"#$%&'()*+,-/:;",
+			input:    "txt-\\041\\042\\043\\044\\045\\046\\047\\050\\051\\052\\053\\054-\\057\\072\\073-test.example.com",
+			expected: "txt-!\"#$%&'()*+,-/:;-test.example.com",
+		},
+		{
+			name:     "Characters escaped <=>?@[\\]^_`{|}~",
+			input:    "txt-\\074\\075\\076\\077\\100\\133\\134\\135\\136_\\140\\173\\174\\175\\176-test2.example.com",
+			expected: "txt-<=>?@[\\]^_`{|}~-test2.example.com",
+		},
+		{
+			name:     "No escaped characters in domain",
+			input:    "txt-awesome-test3.example.com",
+			expected: "txt-awesome-test3.example.com",
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			// actual := convertOctalToAscii(tt.input)
+			// assert.Equal(t, tt.expected, actual)
+
+			actualv := convertOctalToAsciiWithHashTable(tt.input)
+			assert.Equal(t, tt.expected, actualv)
+		})
+	}
+}