# 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:

```bash
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.

```bash
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:

```toml
# 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:

```toml
[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:

```bash
mqtty-cli settings.toml
```

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

```plaintext
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

```cpp
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.
