Added mqtt update subscription triggered on log

src/relations.js

@@ -400,6 +400,7 @@ MqttSource.prototype.log = async function(scanClassId) {
           sql = `${sql} VALUES (?,?);`
           params = [host.id, result.lastID]
           await this.constructor.executeUpdate(sql, params)
+          this.pubsub.publish('mqttUpdate', { mqttUpdate: this.mqtt.service })
         }
         resolve()
       })

src/resolvers/Subscription/index.js

@@ -1,5 +1,7 @@
 const tag = require('./tag')
+const mqttUpdate = require('./mqttUpdate')
 
 module.exports = {
+  ...mqttUpdate,
   ...tag
 }

src/schema.graphql

@@ -356,5 +356,6 @@ type Mutation {
 }
 
 type Subscription {
-  tagUpdate: Tag
+  tagUpdate: Tag,
+  mqttUpdate: Service
 }