Messaging Service Client SDK

Client library for accessing the realtime messaging services of the SmartOcean platform.

The messaging services rely on the MQTT Standard

This client SDK implementation utilises the Paho MQTT library. The Paho MQTT library may also be used directly to access the messaging services in case more advanced use is required.

Credentials

Credentials for accessing the messaging service being consumed must be placed in a .env file with the following content

BROKER_USERNAME=<username>
BROKER_PASSWORD=<password>

Configuration

Broker configuration information must be provided in a yaml configuration file with the following format:

BROKER_HOST: 
BROKER_PORT: 
BROKER_TOPIC: 
TOPIC_QOS: 
CLIENT_ID: 

The name of the configuration file in the example below is to be provided as a command-line argument when running the Python application.

Sample Subscriber

A sample implementation accessing the messaging service as a subscriber:

import sfisop.messaging_sdk.subscriber as mqtt_subscriber
import sfisop.messaging_sdk.configuration as mqtt_configuration

import logging

logging.basicConfig(filename='subscriber_client.log',
                    format="%(asctime)s[%(levelname)s]:%(message)s", encoding='utf-8',
                    level=logging.DEBUG)

logging.info("MQTT Subscriber Client module")


class DataConsumer(mqtt_subscriber.SubscriberClient):

    def __init__(self, config_file : str):

        mqtt_client_config = mqtt_configuration.ClientConfiguration(config_file)

        super().__init__(mqtt_client_config)

    def process_one(self, in_message):

        logging.info(f'Data Consumer process_one: {in_message}')


if __name__ == '__main__':

    config_file = mqtt_configuration.get_config_file()

    data_consumer = DataConsumer(config_file)

    data_consumer.run()

Sample Publisher

A sample implementation accessing the messaging service as a publisher:

from sfisop.messaging_sdk.publisher import PublisherClient
from sfisop.messaging_sdk.configuration import ClientConfiguration, get_config_file

if __name__ == '__main__':

    config_file = get_config_file()

    config = ClientConfiguration(config_file)

    publisher_client = PublisherClient(config)

    publisher_client.publish_one("Hello World Publisher Client")