MQTT Async code

Pushes IOT measurements published on MQTT to Splunk metrics index through HTTP Event Collector or HEC.

Publish to MQTT

The IoT device sends its measurements to MQTT topics having the following structure

RootTopic/thingId/sensorId/metricName

As an example, a board having a MAC address of 00:25:96:FF:FE:12:34:56 fitted with a temperature sensor on port 3 might publish a temperature of 21.3 °C to a topic having the following name:

Things/board-002596FFFE123456/dht11-3/air.temperature

The payload of this topic will be the actual temperature in floating notation: 21.3

The same sensor will publish the humidity to:

Things/board-002596FFFE123456/dht11-3/air.humidity

And the finally the pressure will be published here:

Things/board-002596FFFE123456/dht11-3/air.pressure

Read in Splunk

Splunk will receive a metric having its value read from the payload, its metricName will be the last subtopic name in the hierarchy, and an extra dimension containing the full topic hierarchy.

Example

If the MQTT topic Things/board-002596FFFE123456/dht11-3/air.humidity has a payload of 45.3 Splunk will receive a metric named air.humidity with a value of 45.3 and a dimension named Topic with a value of Things/board-002596FFFE123456/dht11-3/air.humidity

Splunk Analytics dashboard example

Configuration file

There is a single file named mqtt.confthat holds all configurations. A template file mqtt.conf.spechas details of the configurations stanzas and keys.

Local Setup

# Create virtual environment
python3 -m venv .venv
# Select Interpreter in VS Code
# Activate it
source .venv/bin/activate
# make sure pip is up to date
pip install --upgrade pip
# install project's requirements
pip install -r requirements.txt
# Pre commit requirements see: https://www.the-analytics.club/python-code-formatting-git-pre-commit-hook
pip install pre-commit
pre-commit install