MQTT-with-Kaa-server

Porting MQTT for Kaa Open Source middleware IOT platform::

What is MQTT?

MQTT is a publish/subscribe, extremely simple and lightweight messaging protocol, designed for constrained devices and low-bandwidth, high-latency or unreliable networks. Since it is perfectly suitable for IOT/M2M communication, we opted to use MQTT. Moreover, we are also using it as communication channel between Kaa server and Dashboard.

For more details about MQTT, Kindly refer http://mqtt.org/

How the MQTT communicate with Kaa server and external application?

https://github.com/ethicstechOSS/MQTT-with-Kaa-server/tree/ethicstechOSS-images/mqtt_kaa.jpg

We are here using MQTT at our dashboard side to exchange the datas between the dashboard application and Kaa server. Kaa server has log appenders such as MongoDB, Cassandra and other some databases. If we are using a dashboard, we need to stream the data directly to the dashboard which will cause more performance overhead in the databases. So we are using this MQTT protocol to append our logs to the MQTT server which can be subscribed and streaming data can be displayed. Since MQTT is open source, we opted to use it.

1.How to compile the source

NOTE : We tried the below steps on Ubuntu 16.04, 64bit version. Kaa server : 0.9.0

Open terminal, do an update and then install mosquitto dependencies. To install mosquitto you must create a mosquitto user.

$sudo adduser mosquitto

$sudo apt-get update

$sudo apt-get install build-essential libwrap0-dev libssl-dev libc-ares-dev uuid-dev xsltproc

$sudo cd /home/mosquitto

$sudo wget http://mosquitto.org/files/source/mosquitto-1.4.8.tar.gz

$sudo tar xvzf mosquitto-1.4.8.tar.gz

$sudo cd mosquitto-1.4.8

Run make to compile and make install:

$sudo make

$sudo make install

2.Setup Mosquitto

Create a mosquitto user/password: the command below will create a user owntracks, you can change

$sudomkdir /var/lib/mosquitto/

$sudo chown mosquitto:mosquitto /var/lib/mosquitto/ -R

$sudo mosquitto_passwd -c /etc/mosquitto/pwfile YOUR_MOSQUITTO_USER_NAME

Here YOUR_MOSQUITTO_USER_NAME - your mosquitto username

you will be prompted to enter a password. Create the directory where persistence db files will be stored, change owner to mosquitto:

$sudo mkdir /var/lib/mosquitto/

Create a config file by copying the example configuration:

$sudo cp /etc/mosquitto/mosquitto.conf.example /etc/mosquitto/mosquitto.conf

$sudo gedit /etc/mosquitto/mosquitto.conf

Open the file by using any one of the editor like "gedit" or "vim" and at the end of the config file, add a block of all suggested configuation changes like the below. (Replace with the IP address & port number).

listener 8883

persistence true

persistence_location /var/lib/mosquitto/

persistence_file mosquitto.db

log_dest syslog

log_dest stdout

log_dest topic

log_type error

log_type warning

log_type notice

log_type information

connection_messages true

log_timestamp true

allow_anonymous false

password_file /etc/mosquitto/pwfile

Finally be sure to run:

$sudo /sbin/ldconfig

3.Run/Test Mosquitto:

$sudo mosquitto -c /etc/mosquitto/mosquitto.conf

It should start running without error.

Then open another terminal/tab try the following command.

$sudo mosquitto_sub -h -p 8883 -v -t 'YOUR_TOPIC/#' -u YOUR_MOSQUITTO_USER_NAME -P YourPassword

Example : $sudo mosquitto_sub -h 192.168.0.105 -p 8883 -v -t 'ethicstech/#' -u ethicstech -P 1234

If everything went correctly you should see no errors when executing this command and in the window where mosquitto is running should acknowledge the connection. if so, create an upstart file to autorun mosquitto:

$sudo gedit /etc/init/mosquitto.conf

Then paste the below.

description "Mosquitto MQTT broker"

start on net-device-up

respawn

exec /usr/sbin/mosquitto -c /etc/mosquitto/mosquitto.conf

Start Mosquitto server by using the following command:

$sudo service mosquitto srart

Now you have a Mosquitto broker working on your server. For any further queries in the setup processof mosquitto refer the link: https://www.digitalocean.com/community/questions/how-to-setup-a-mosquitto-mqtt-server-and-receive-data-from-owntracks

4.Paho MQTT Broker appender configuration on kaa server version 0.9.0.

Compile the source code of mosquitto log appender for kaa server.

Install git, maven and clone the source code from the repository.

$sudo apt-get install git maven

$git clone https://github.com/ethicstechOSS/MQTT-with-Kaa-server.git

$cd

$mvn clean install

After the successful build, you will get the JAR file at /target/pahomqtt-appender-0.9.0.jar. The compiled JAR file also availale on our repository.

5.Install log appender in kaa server

Copy the generated JAR file in the location at kaa node: /usr/lib/kaa-node/lib/
Restart the kaa server node services.

$sudo service kaa-node restart

6.Add Log Appender to your application in Kaa

Login to your kaa server admin page using a developer account.
Under applications select-> YOUR_APPLICATION -> Log Appenders
Select add Log appender
Select the type as PahoMqtt and use the configruations as per your mosquitto server.
See the bellow screen shot.

https://github.com/ethicstechOSS/MQTT-with-Kaa-server/blob/ethicstechOSS-images/paho_kaa.png

vtongcoder/MQTT-with-Kaa-server

MQTT-with-Kaa-server