feat: add support for .vn domain (#244)

* Add adapter for .vn domain

* [internal/whois] impl adapter_vn

internal/whois/adapter_vn.go

@@ -0,0 +1,67 @@
+package whois
+
+import (
+	"net/url"
+	"strings"
+
+	"github.com/domainr/whois"
+)
+
+// Adapter for whois.net.vn
+type vnAdapter struct{}
+
+func (a *vnAdapter) Prepare(req *whois.Request) error {
+	req.URL = generateVnWhoisRequestUrl(req.Query)
+	// Override request body to avoid any conflict.
+	req.Body = nil
+
+	return nil
+}
+
+func (a *vnAdapter) Text(res *whois.Response) ([]byte, error) {
+	return parseVnWhoisResponseBody(res.Body), nil
+}
+
+func init() {
+	whois.BindAdapter(
+		&vnAdapter{},
+		"whois.net.vn",
+	)
+}
+
+// Generate URL for .vn whois request.
+// Query sent to whois.net.vn should go to `/whois.php` route with `act` & `domain` parameters.
+func generateVnWhoisRequestUrl(query string) string {
+	whoisEndpoint := "https://whois.net.vn/whois.php?"
+
+	whoisQueryParams := url.Values{}
+	whoisQueryParams.Set("act", "getwhois")
+	whoisQueryParams.Set("domain", query)
+
+	return whoisEndpoint + whoisQueryParams.Encode()
+}
+
+// Remove HTML Tags, tab characters, exceeding spaces, correct some keys and generate a registar field
+// to avoid parsing errors in later step.
+func parseVnWhoisResponseBody(bodyContent []byte) []byte {
+	htmlTags := []string{"<br/>", "<div>", "</div>"}
+
+	resBodyString := string(bodyContent)
+
+	// Remove HTML tag (<br>, <div>).
+	for _, htmlTag := range htmlTags {
+		resBodyString = strings.ReplaceAll(resBodyString, htmlTag, "")
+	}
+
+	// Remove tab characters.
+	resBodyString = strings.ReplaceAll(resBodyString, "\t", "")
+
+	// Remove exceeding spaces & correct some keys in response.
+	resBodyString = strings.ReplaceAll(resBodyString, "Expired Date : ", "Expire Date:")
+	resBodyString = strings.ReplaceAll(resBodyString, "Issue Date : ", "Issue Date:")
+
+	// Generate Registrar field.
+	resBodyString = "Registrar WHOIS Server: Not available" + resBodyString
+
+	return []byte(resBodyString)
+}

internal/whois/whois.go

@@ -124,7 +124,12 @@ func (c whoisClient) request(ctx context.Context, domain, host string) (string,
 	if err != nil {
 		return "", fmt.Errorf("failed to fetch whois request: %w", err)
 	}
-	body := string(resp.Body)
+	respText, err := resp.Text()
+	if err != nil {
+		return "", fmt.Errorf("failed to parse response body into text: %w", err)
+	}
+
+	body := string(respText)
 
 	if host == "" {
 		// do not recurse

internal/whois/whois_test.go

@@ -40,13 +40,14 @@ func TestWhoisParsing(t *testing.T) {
 		{domain: "GOOGLE.RS", host: "", err: ""},
 		{domain: "google.co.th", host: "", err: ""},
 		{domain: "google.fi", host: "", err: ""},
+		{domain: "google.vn", host: "whois.net.vn", err: ""},
 	} {
 		tt := tt
 		t.Run(tt.domain, func(t *testing.T) {
 			t.Parallel()
 			is := is.New(t)
 
-			ctx, cancel := context.WithTimeout(context.Background(), 2*time.Second)
+			ctx, cancel := context.WithTimeout(context.Background(), 3*time.Second)
 			t.Cleanup(cancel)
 
 			expiry, err := NewClient().ExpireTime(ctx, tt.domain, tt.host)