chore: release v0.23.0

internal/relaydev/relaydev.go

@@ -7,6 +7,10 @@
 //   - KMTronic LAN 8-relay WEB board — 8 relays. Control: GET /FF{rr}{ss}
 //     (rr = 01..08, ss = 01 on / 00 off); status: GET /status.xml with
 //     <relay1>..<relay8> (relay0 is reserved). Optional HTTP basic auth.
+//   - Dingtian IOT relay (DTWONDER) — 2/4/8/16/24/32 relays over its HTTP GET
+//     CGI. Control: GET /relay_cgi.cgi?type=0&relay=N&on=1&time=0&pwd=P&;
+//     status: GET /relay_cgi_load.cgi. Both answer &-separated fields.
+//     (IOT Relay Programming Manual V1.9.8.1, §3.)
 //
 // A Device presents the same surface to the app regardless of wire protocol.
 package relaydev
@@ -173,3 +177,119 @@ func (k *kmtronic) Status(ctx context.Context) ([]bool, error) {
 	}
 	return out, nil
 }
+
+// ── Dingtian IOT relay (DTWONDER) ──────────────────────────────────────
+//
+// The board speaks several protocols (Modbus, MQTT, CoAP, its own binary); we
+// use the HTTP GET CGI, which needs no connection state and matches how the
+// other network boards here are driven.
+//
+// Both endpoints answer &-separated fields, first one 0 on success:
+//
+//	/relay_cgi_load.cgi                                  → &0&4&1&0&1&0&
+//	                                                       result, count, r1…rN
+//	/relay_cgi.cgi?type=0&relay=0&on=1&time=0&pwd=0&     → &0&0&0&1&0&
+//	                                                       result, type, relay, on, time
+//
+// NOTE the relay index in the URL is ZERO-based (relay=0 is relay 1), while the
+// Device interface is 1-based like every other board here.
+type dingtian struct {
+	host    string
+	session string // optional: the board can require "Cookie: session=<id>"
+	pwd     string // CGI password, 0–9999; "0" (or blank) when none is set
+	count   int
+}
+
+// NewDingtian builds a Dingtian IOT relay client. session is the HTTP session ID
+// when the board has "HTTP Session" enabled (blank otherwise); pwd is its relay
+// password (blank or "0" when none).
+func NewDingtian(host, session, pwd string, count int) Device {
+	if count <= 0 {
+		count = 2
+	}
+	if strings.TrimSpace(pwd) == "" {
+		pwd = "0"
+	}
+	return &dingtian{host: host, session: strings.TrimSpace(session), pwd: strings.TrimSpace(pwd), count: count}
+}
+
+func (d *dingtian) Count() int   { return d.count }
+func (d *dingtian) Close() error { return nil } // stateless HTTP, nothing to release
+
+// getCGI issues the GET with the session cookie the board may require.
+func (d *dingtian) getCGI(ctx context.Context, url string) ([]byte, error) {
+	req, err := http.NewRequestWithContext(ctx, http.MethodGet, url, nil)
+	if err != nil {
+		return nil, err
+	}
+	if d.session != "" {
+		req.Header.Set("Cookie", "session="+d.session)
+	}
+	resp, err := httpClient().Do(req)
+	if err != nil {
+		return nil, err
+	}
+	defer resp.Body.Close()
+	body, _ := io.ReadAll(resp.Body)
+	if resp.StatusCode < 200 || resp.StatusCode >= 300 {
+		return nil, fmt.Errorf("http %d: %s", resp.StatusCode, strings.TrimSpace(string(body)))
+	}
+	return body, nil
+}
+
+// dtFields splits an &-separated CGI reply into its fields, dropping the empty
+// ones the leading and trailing "&" produce.
+func dtFields(body []byte) []string {
+	var out []string
+	for _, f := range strings.Split(strings.TrimSpace(string(body)), "&") {
+		if f = strings.TrimSpace(f); f != "" {
+			out = append(out, f)
+		}
+	}
+	return out
+}
+
+func (d *dingtian) Set(ctx context.Context, relay int, on bool) error {
+	if relay < 1 || relay > d.count {
+		return fmt.Errorf("relay %d out of range 1..%d", relay, d.count)
+	}
+	state := 0
+	if on {
+		state = 1
+	}
+	// type=0 is plain ON/OFF (1 = jogging, 2 = delay, 3 = flash, 4 = toggle),
+	// and time is then unused.
+	body, err := d.getCGI(ctx, fmt.Sprintf("http://%s/relay_cgi.cgi?type=0&relay=%d&on=%d&time=0&pwd=%s&",
+		d.host, relay-1, state, d.pwd))
+	if err != nil {
+		return err
+	}
+	// A wrong password or session answers 200 with a non-zero result (e.g.
+	// "&302&/&"), so the HTTP status alone does not tell us it worked.
+	if f := dtFields(body); len(f) == 0 || f[0] != "0" {
+		return fmt.Errorf("dingtian: refused (%s) — check the relay password and the HTTP session ID",
+			strings.TrimSpace(string(body)))
+	}
+	return nil
+}
+
+func (d *dingtian) Status(ctx context.Context) ([]bool, error) {
+	body, err := d.getCGI(ctx, fmt.Sprintf("http://%s/relay_cgi_load.cgi", d.host))
+	if err != nil {
+		return nil, err
+	}
+	f := dtFields(body)
+	if len(f) < 2 || f[0] != "0" {
+		return nil, fmt.Errorf("dingtian: bad status reply %q", strings.TrimSpace(string(body)))
+	}
+	// The board reports its own relay count; trust it over the configured one so
+	// a mis-set channel count doesn't silently hide relays.
+	if n, e := strconv.Atoi(f[1]); e == nil && n > 0 && n <= 32 {
+		d.count = n
+	}
+	out := make([]bool, d.count)
+	for i := 0; i < d.count && i+2 < len(f); i++ {
+		out[i] = f[i+2] == "1"
+	}
+	return out, nil
+}