feat: mqtt wildcards support

server/monitor-types/mqtt.js

@@ -48,6 +48,21 @@ class MqttMonitorType extends MonitorType {
         }
     }
 
+    /**
+     * 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} subscribedTopic MQTT subscribed topic
+     * @returns {RegExp} RegExp if the actual topic matches the subscribed topic
+     */
+    static mqttTopicRegex(subscribedTopic) {
+        //eslint-disable-next-line
+        subscribedTopic = subscribedTopic.replace(/([$.|?*{}()\[\]\\])/g, "\\$1"); // Escape special regex chars except + and #
+        //eslint-disable-next-line
+        subscribedTopic = subscribedTopic.replace(/(\+)/g, ".+"); // Replace + with regex for one or more characters except slash
+        subscribedTopic = subscribedTopic.replace(/#/g, ".*"); // Replace # with regex for zero or more levels (including slashes)
+        return new RegExp(`^${subscribedTopic}$`);
+    }
+
     /**
      * Connect to MQTT Broker, subscribe to topic and receive message as String
      * @param {string} hostname Hostname / address of machine to test
@@ -89,12 +104,15 @@ class MqttMonitorType extends MonitorType {
                 clientId: "uptime-kuma_" + Math.random().toString(16).substr(2, 8)
             });
 
+            let 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 +128,7 @@ class MqttMonitorType extends MonitorType {
             });
 
             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 +100,58 @@ describe("MqttMonitorType", {
             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 check specifically for the escaping of '?' regex char", () => {
+        const regex = MqttMonitorType.mqttTopicRegex("sensor.pomme/tempera?ture");
+        assert.ok(regex.test("sensor.pomme/tempera?ture") === true);
+        assert.ok(regex.test("sensor.pomme/humi?dity") === false);
+    });
+
+    test("should check specifically for the escaping of '*' regex char", () => {
+        const regex = MqttMonitorType.mqttTopicRegex("sensor.pomme/tempera*ture");
+        assert.ok(regex.test("sensor.pomme/tempera*ture") === true);
+        assert.ok(regex.test("sensor.pomme/humi*dity") === 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);
+    });
 });