collect and show mqtt state for nodes

src/mqtt.js

@@ -225,6 +225,36 @@ client.on("connect", () => {
 client.on("message", async (topic, message) => {
     try {
 
+        // handle node status
+        if(topic.includes("/stat/!")){
+            try {
+
+                // get node id and status
+                const nodeIdHex = topic.split("/").pop();
+                const mqttConnectionState = message.toString();
+
+                // convert node id hex to int value
+                const nodeId = BigInt('0x' + nodeIdHex.replaceAll("!", ""));
+
+                // update mqtt connection state for node
+                await prisma.node.updateMany({
+                    where: {
+                        node_id: nodeId,
+                    },
+                    data: {
+                        mqtt_connection_state: mqttConnectionState,
+                        mqtt_connection_state_updated_at: new Date(),
+                    },
+                });
+
+                // no need to continue with this mqtt message
+                return;
+
+            } catch(e) {
+                console.error(e);
+            }
+        }
+
         // decode service envelope
         const envelope = ServiceEnvelope.decode(message);
         if(!envelope.packet){