Messages

What are "Messages"?

"Messages" are the items sent to the central backend of the network via MQTT. There are three types of messages: DataMessage, LogMessage and ConfigMessage. Below, you can find the internal definition of the message schema: it combines a timestamp with a message body for one of the three message types.

import src
 
messaging_agent = src.utils.MessagingAgent()
 
# send measurement datapoints
messaging_agent.add_message(
    src.types.DataMessageBody(
        message_body={"temperature": 22.7, "humidity": 0.63}
    )
)
 
# send log messsages
messaging_agent.add_message(
    src.types.LogMessageBody(
        level="WARNING",
        subject="CPU load is high",
        body="The CPU load was above 75% for the last 5 minutes.",
    )
)
 
# send config "received"/"accepted"/"rejected"/"startup"
messaging_agent.add_message(
    src.types.ConfigMessageBody(
        status="received",
        config={"version": "0.2.0", ...}
    )
)

The different messages will be sent to the configured IOT backend via MQTT.

However, you do not have to manually send out log messages because the logger already does that (see config.logging_verbosity.message_sending):

logger = src.utils.Logger(config=..., origin="some-place")
logger.info("CPU load is high", details="The CPU load was above 75% for the last 5 minutes.")

Local Message Archive

In case the backend is offline for a while or the connection between MQTT broker and server breaks, the messages are stored locally in data/messages/. There is one file YYYY-MM-DD.csv" per day, and each line can be parsed using the schema below. The file name relates to the system date (not UTC date). The following script does just that:

import src
 
with open("data/messages/2021-01-01.csv", "r") as f:
    messages = [
        src.types.MessageArchiveItem.model_validate_json(line)
        for line in f.read().strip("\n ").split()
    ]

The exact schema of src.types.MessageArchiveItem is defined in the API Reference section.

Logging State