ki2-mqtty-cli 1.2.1

Command-line utility designed to facilitate the interconnection between serial devices and an MQTT server. This project is based on the `mqtty` library and allows simple configuration using a TOML file.

mqtty-cli

mqtty-cli is a command-line utility designed to facilitate the interconnection between serial devices and an MQTT server. This project is based on the mqtty library and allows simple configuration using a TOML file.

Installation

You can install mqtty-cli directly from PyPI:

pip install ki2-mqtty-cli

Usage

Basic Command

Once installed, the mqtty-cli command will be available. You can use it to start the interconnection using a TOML configuration file.

mqtty-cli <path-to-settings.toml>

If no path is provided, the program will attempt to load a configuration file named settings.toml from the current directory. You can also specify the path using the MQTTY_CONFIG environment variable.

Configuration

The configuration file must be written in TOML format. Here is an example settings.toml file:

# MQTT Configuration
[mqtt]
host = "localhost"
port = 1883
startup_wait_time = 5
notification_topic = "mqtty/notifications"

[[devices]]
# Device 1 configuration
topic = "device/1"
port = "/dev/ttyACM0"
baudrate = 9600

[[devices]]
# Device 2 configuration
topic = "device/2"
port = "/dev/ttyACM1"
baudrate = 9600

Field Details

MQTT Section ([mqtt])

Field	Type	Default	Description
host	string	"localhost"	Address of the MQTT server
port	int	1883	Port of the MQTT server
auth	table	None	Authentication configuration (optional)
startup_wait_time	int	0	Time to wait (in seconds) before connecting to the MQTT server
notification_topic	string	None	MQTT topic where mqtty-cli can send notifications (e.g., error messages)
pending_calls_threshold	int	None	Maximum number of pending publications before logging a warning

If authentication is required, add the following fields:

[mqtt.auth]
username = "my-username"
password = "my-password"

Devices Section ([[devices]])

Each serial device must be defined as a table in a [[devices]] list.

Field	Type	Default	Description
topic	string	-	MQTT topic associated with the device
port	string	-	Serial port of the device (e.g., /dev/ttyACM0)
name	string	null	Optional name for the device; defaults to its port if not provided
optional	bool	true	If true, the program checks if the port exists before registering the device
baudrate	int	9600	Serial communication speed
bytesize	int	8	Size of serial data
parity	string	"None"	Parity (None, Even, Odd, Mark, Space, or N, E, O, M, S)
stopbits	float	1	Number of stop bits
timeout	int / null	null	Timeout in seconds (null to disable)
xonxoff	bool	False	XON/XOFF flow control
rtscts	bool	False	RTS/CTS flow control
write_timeout	float / null	null	Write timeout
dsrdtr	bool	False	DSR/DTR flow control
inter_byte_timeout	float / null	null	Timeout between bytes
exclusive	bool / null	null	Exclusive mode for the serial port
endline_char	string (1)	"\n"	End-of-line character
mqtt_start	string (1)	"@"	Start character for MQTT messages
mqtt_separator	string (1)	":"	Separator in MQTT messages

Example Execution

1. Create a settings.toml configuration file with your parameters.
2. Run the following command:

mqtty-cli settings.toml

You will see a message indicating that the devices have been configured and the interconnection has started:

Path = settings.toml
New device '/dev/ttyACM0' on topic 'device/1'
New device '/dev/ttyACM1' on topic 'device/2'

Programming Example for Serial Devices

For serial devices, all messages received on the associated topic are sent directly to the device without any specific start or end characters.

To publish to a specific topic from the device, messages written to the serial port should follow the format:

@<topic>:<payload>\n

• <topic> is the target MQTT topic.
• <payload> is the message to be published.

Arduino Example

void setup() {
  Serial.begin(9600);
  Serial.println("Arduino is ready!");
}

void loop() {
  // Send data to the MQTT broker
  if (Serial.available()) {
    String topic = "other-topic"; // Specify the target topic
    String payload = Serial.readStringUntil('\n');
    Serial.print("@");
    Serial.print(topic);
    Serial.print(":");
    Serial.println(payload);
  }
}

In this example, the Arduino listens on its serial input and formats outgoing messages to publish to the topic other-topic.

License

This project is distributed under the MIT License. See the LICENSE file for more details.