From 574cb8bb49527d9d1a564beb787f32409ba9d341 Mon Sep 17 00:00:00 2001
From: esensar <esarajcic1@etf.unsa.ba>
Date: Thu, 26 Apr 2018 14:12:20 +0200
Subject: [PATCH] Add devices module with MQTT client

---
 app/__init__.py             | 23 +++++++++--------------
 app/mod_devices/__init__.py | 34 ++++++++++++++++++++++++++++++++++
 2 files changed, 43 insertions(+), 14 deletions(-)
 create mode 100644 app/mod_devices/__init__.py

diff --git a/app/__init__.py b/app/__init__.py
index 767329b..4b8782d 100644
--- a/app/__init__.py
+++ b/app/__init__.py
@@ -1,23 +1,18 @@
+import atexit
 from flask import Flask
-from flask_mqtt import Mqtt
+from app.mod_devices import setup_mqtt, tear_down_mqtt
 
 app = Flask(__name__, instance_relative_config=True)
 app.config.from_object('config')
 app.config.from_pyfile('config.py')
-mqtt = Mqtt(app)
+
+def on_stop():
+    print('Application stopping')
+    tear_down_mqtt()
+
+setup_mqtt(app)
+atexit.register(on_stop)
 
 @app.route("/")
 def hello():
     return "Hello World!"
-
-@mqtt.on_connect()
-def handle_connect(client, userdata, flags, rc):
-    mqtt.subscribe('topic/state')
-
-@mqtt.on_message()
-def handle_mqtt_message(client, userdata, message):
-    data = dict(
-        topic=message.topic,
-        payload=message.payload.decode()
-    )
-    print(message.payload.decode())
diff --git a/app/mod_devices/__init__.py b/app/mod_devices/__init__.py
new file mode 100644
index 0000000..cf5851e
--- /dev/null
+++ b/app/mod_devices/__init__.py
@@ -0,0 +1,34 @@
+from flask_mqtt import Mqtt
+
+mqtt = Mqtt()
+
+def setup_mqtt(app):
+    mqtt.init_app(app)
+    mqtt.client.on_message = handle_mqtt_message
+    mqtt.client.on_subscribe = handle_subscribe
+    print('MQTT client initialized')
+
+def tear_down_mqtt():
+    mqtt.unsubscribe_all()
+    if hasattr(mqtt, 'client') and mqtt.client is not None:
+        mqtt.client.disconnect()
+    print('MQTT client destroyed')
+
+@mqtt.on_connect()
+def handle_connect(client, userdata, flags, rc):
+    print('MQTT client connected')
+    mqtt.subscribe('topic/state')
+
+@mqtt.on_disconnect()
+def handle_disconnect():
+    print('MQTT client disconnected')
+
+def handle_subscribe(client, userdata, mid, granted_qos):
+    print('MQTT client subscribed')
+
+def handle_mqtt_message(client, userdata, message):
+    data = dict(
+        topic=message.topic,
+        payload=message.payload.decode()
+    )
+    print(message.payload.decode())