Initial commit

checker/interactive.go

@@ -0,0 +1,134 @@
+//go:build standalone
+
+package checker
+
+import (
+	"errors"
+	"net/http"
+	"strconv"
+	"strings"
+
+	sdk "git.happydns.org/checker-sdk-go/checker"
+)
+
+// RenderForm implements server.Interactive: the human-facing form
+// exposed at GET /check when the checker runs as a standalone binary.
+func (p *smtpProvider) RenderForm() []sdk.CheckerOptionField {
+	return []sdk.CheckerOptionField{
+		{
+			Id:          "domain",
+			Type:        "string",
+			Label:       "Domain",
+			Placeholder: "example.com",
+			Required:    true,
+			Description: "The email domain to probe. MX records are looked up live.",
+		},
+		{
+			Id:          "helo_name",
+			Type:        "string",
+			Label:       "EHLO hostname",
+			Placeholder: defaultEHLOName,
+			Default:     defaultEHLOName,
+			Description: "The hostname announced in EHLO/HELO. Use a name that resolves and has a valid PTR.",
+		},
+		{
+			Id:      "timeout",
+			Type:    "number",
+			Label:   "Per-endpoint timeout (seconds)",
+			Default: 12,
+		},
+		{
+			Id:      "test_null_sender",
+			Type:    "bool",
+			Label:   "Probe null sender (MAIL FROM:<>)",
+			Default: true,
+		},
+		{
+			Id:      "test_postmaster",
+			Type:    "bool",
+			Label:   "Probe RCPT TO:<postmaster@domain>",
+			Default: true,
+		},
+		{
+			Id:      "test_open_relay",
+			Type:    "bool",
+			Label:   "Probe open-relay posture",
+			Default: true,
+		},
+		{
+			Id:          "test_probe_address",
+			Type:        "string",
+			Label:       "Open-relay probe recipient",
+			Placeholder: "postmaster@example.com",
+			Default:     "postmaster@example.com",
+		},
+	}
+}
+
+// ParseForm implements server.Interactive: turns the submitted HTML
+// form into the CheckerOptions that Collect expects. No AutoFill is
+// performed by a host here; Collect falls back to a live MX lookup when
+// no "service" payload is supplied, so forwarding the bare domain is
+// enough.
+func (p *smtpProvider) ParseForm(r *http.Request) (sdk.CheckerOptions, error) {
+	domain := strings.TrimSpace(r.FormValue("domain"))
+	domain = strings.TrimSuffix(domain, ".")
+	if domain == "" {
+		return nil, errors.New("domain is required")
+	}
+	if !isValidHostname(domain) {
+		return nil, errors.New("invalid domain")
+	}
+
+	opts := sdk.CheckerOptions{
+		"domain": domain,
+	}
+
+	if helo := strings.TrimSpace(r.FormValue("helo_name")); helo != "" {
+		if !isValidHostname(helo) {
+			return nil, errors.New("invalid helo_name")
+		}
+		opts["helo_name"] = helo
+	}
+	if raw := strings.TrimSpace(r.FormValue("timeout")); raw != "" {
+		v, err := strconv.ParseFloat(raw, 64)
+		if err != nil {
+			return nil, errors.New("timeout must be a number")
+		}
+		opts["timeout"] = v
+	}
+	opts["test_null_sender"] = parseBool(r, "test_null_sender", true)
+	opts["test_postmaster"] = parseBool(r, "test_postmaster", true)
+	opts["test_open_relay"] = parseBool(r, "test_open_relay", true)
+	if probe := strings.TrimSpace(r.FormValue("test_probe_address")); probe != "" {
+		if !isValidMailbox(probe) {
+			return nil, errors.New("invalid test_probe_address")
+		}
+		opts["test_probe_address"] = probe
+	}
+
+	return opts, nil
+}
+
+// parseBool reads a checkbox-style field. HTML forms omit unchecked
+// checkboxes entirely, so a missing key means false, but only if the
+// form was actually submitted (presence of the sentinel); we use the
+// default when the field is not present at all.
+func parseBool(r *http.Request, key string, def bool) bool {
+	if _, ok := r.Form[key]; !ok {
+		// When the form has been parsed and _no_ checkbox was checked,
+		// we still want false rather than the default. Detect a
+		// submitted form by the presence of the required "domain" key.
+		if _, submitted := r.Form["domain"]; submitted {
+			return false
+		}
+		return def
+	}
+	v := strings.ToLower(strings.TrimSpace(r.FormValue(key)))
+	switch v {
+	case "", "0", "false", "off", "no":
+		return false
+	default:
+		return true
+	}
+}