feat: mqtt wildcards support

server/monitor-types/mqtt.js

@@ -2,6 +2,7 @@
 const { log, UP } = require("../../src/util");
 const mqtt = require("mqtt");
 const jsonata = require("jsonata");
+const { regex } = require("nostr-tools/nip30");
 
 class MqttMonitorType extends MonitorType {
     name = "mqtt";
@@ -48,6 +49,19 @@
         }
     }
 
+    /**
+     * This function checks if the actual MQTT topic matches the subscribed topic.
+     * To handle MQTT wildcards, it converts the subscribed topic into a regex pattern.
+     * @param {string} subcribedTopic MQTT subscribed topic
+     * @returns {RegExp} RegExp if the actual topic matches the subscribed topic
+     */
+    static mqttTopicRegex(subcribedTopic) {
+        subcribedTopic = subcribedTopic.replace(/([$.|?*{}()\[\]\\])/g, '\\$1'); // Escape special regex chars except + and #
+        subcribedTopic = subcribedTopic.replace(/\+/g, '[^/]+'); // Replace + with regex for one or more characters except slash
+        subcribedTopic = subcribedTopic.replace(/#/g, '.*'); // Replace # with regex for zero or more characters until next slash
+        return new RegExp(`^${subcribedTopic}$`);;
+    }
+
     /**
      * Connect to MQTT Broker, subscribe to topic and receive message as String
      * @param {string} hostname Hostname / address of machine to test
@@ -89,12 +103,15 @@
                 clientId: "uptime-kuma_" + Math.random().toString(16).substr(2, 8)
             });
 
+            var regexTopic;
+
             client.on("connect", () => {
                 log.debug("mqtt", "MQTT connected");
 
                 try {
                     client.subscribe(topic, () => {
                         log.debug("mqtt", "MQTT subscribed to topic");
+                        regexTopic = MqttMonitorType.mqttTopicRegex(topic);
                     });
                 } catch (e) {
                     client.end();
@@ -110,7 +127,7 @@
             });
 
             client.on("message", (messageTopic, message) => {
-                if (messageTopic === topic) {
+                if (regexTopic.test(messageTopic)) {
                     client.end();
                     clearTimeout(timeoutID);
                     resolve(message.toString("utf8"));

test/backend-test/test-mqtt.js

@@ -100,4 +100,46 @@
             new Error("Message received but value is not equal to expected value, value was: [present]")
         );
     });
+
+    test('should match exact topic without wildcards', () => {
+        const regex = MqttMonitorType.mqttTopicRegex('sensor/temperature');
+        assert.ok(regex.test('sensor/temperature') === true);
+        assert.ok(regex.test('sensor/humidity') === false);
+    });
+
+    test('should match exact topic without wildcards but with special characters', () => {
+        const regex = MqttMonitorType.mqttTopicRegex('sensor.pomme/temperature');
+        assert.ok(regex.test('sensor.pomme/temperature') === true);
+        assert.ok(regex.test('sensor.pomme/humidity') === false);
+    });
+
+    test('should match + wildcard for single level', () => {
+        const regex = MqttMonitorType.mqttTopicRegex('sensor/+/temperature');
+        assert.ok(regex.test('sensor/room1/temperature') === true)
+        assert.ok(regex.test('sensor/room2/temperature') === true)
+        assert.ok(regex.test('sensor/room1/humidity') === false)
+        assert.ok(regex.test('sensor/temperature') === false)
+    });
+
+    test('should match # wildcard for multi-level', () => {
+        const regex = MqttMonitorType.mqttTopicRegex('sensor/#');
+        assert.ok(regex.test('sensor/room1') === true);
+        assert.ok(regex.test('sensor/room1/temperature') === true);
+        assert.ok(regex.test('sensor/') === true);
+        assert.ok(regex.test('actuator/room1') === false);
+    });
+
+    test('should combine + and # wildcards', () => {
+        const regex = MqttMonitorType.mqttTopicRegex('sensor/+/status/#');
+        assert.ok(regex.test('sensor/room1/status/online') === true);
+        assert.ok(regex.test('sensor/room2/status/offline/extra') === true);
+        assert.ok(regex.test('sensor/status') === false);
+        assert.ok(regex.test('sensor/room1') === false);
+    });
+
+    test('should escape special regex characters in topic', () => {
+        const regex = MqttMonitorType.mqttTopicRegex('some.topic/+/value$');
+        assert.ok(regex.test('some.topic/abc/value$') === true);
+        assert.ok(regex.test('some.topic/abc/value') === false);
+    });
 });