6 releases

0.3.0-alpha.1 Dec 9, 2021
0.2.1 Jul 30, 2021
0.1.2 Jul 21, 2021
0.1.0 Nov 29, 2020

#732 in Hardware support

MIT/Apache

170KB
4K SLoC

gatt

Bluetooth Low Energy Generic Attribute Profile

ref BLUETOOTH CORE SPECIFICATION Version 5.1 | Vol 3, Part G Generic Attribute Profile (GATT)

Example

use gatt::{CharacteristicProperties, Registration, Server};
use gatt::services as srv;
use gatt::characteristics as ch;

#[derive(Debug, Clone, PartialEq, Eq, Hash)]
enum Token {
    DeviceName,
    BatteryLevelNotify,
}

fn new_registration() -> Registration<Token> {
    let mut registration = Registration::new();

    registration.add_primary_service(srv::GENERIC_ACCESS);
    registration.add_characteristic_with_token(
        Token::DeviceName,
        ch::DEVICE_NAME,
        "abc",
        CharacteristicProperties::WRITE,
    );
    registration.add_characteristic(
        ch::APPEARANCE,
        0x03c0u16.to_le_bytes().to_vec(),
        CharacteristicProperties::READ,
    );

    registration.add_primary_service(srv::GENERIC_ATTRIBUTE);
    registration.add_characteristic(
        ch::SERVICE_CHANGED,
        "",
        CharacteristicProperties::INDICATE,
    );

    registration.add_primary_service(srv::DEVICE_INFORMATION);
    registration.add_characteristic(
        ch::MANUFACTURER_NAME_STRING,
        "機械",
        CharacteristicProperties::READ,
    );
    registration.add_characteristic(
        ch::MODEL_NUMBER_STRING,
        "A123",
        CharacteristicProperties::READ,
    );
    registration.add_characteristic(
        ch::SERIAL_NUMBER_STRING,
        "333-444",
        CharacteristicProperties::READ,
    );

    registration.add_primary_service(srv::BATTERY);
    registration.add_characteristic_with_token(
        Token::BatteryLevelNotify,
        ch::BATTERY_LEVEL,
        "",
        CharacteristicProperties::NOTIFY,
    );

    registration
}

#[tokio::main(flavor = "current_thread")]
async fn main() -> anyhow::Result<()> {
    use std::io::stdin;
    use tokio::task::spawn_blocking;
    use tokio::io::AsyncWriteExt;

    let mut server = Server::bind()?;
    let mut connection = server.accept(new_registration()).await?.unwrap();
    let mut events = connection.events();
    let mut notification = connection.notification(&Token::BatteryLevelNotify)?;
    let task = connection.run();
    tokio::pin!(task);

    let mut n = 0;
    loop {
        tokio::select! {
            r = Pin::new(&mut task) => {
                r?;
                break;
            }

            maybe_line = spawn_blocking(|| stdin().read_line(&mut String::new())) => {
                maybe_line??;
                notification.write_all(&[n]).await?;
                n += 1;
            }

            event = events.next() => {
                if let Some(event) = event {
                    println!("{:?}", event);
                }
            }
        }
    }
    // ...
    # Ok(())
}

Supported target

  • x86_64-unknown-linux-gnu

Tested on Linux 5.13 (Arch Linux)

License

Licensed under either of

Contribution

Unless you explicitly state otherwise, any contribution intentionally submitted for inclusion in the work by you, as defined in the Apache-2.0 license, shall be dual licensed as above, without any additional terms or conditions.!

License: MIT OR Apache-2.0

Dependencies

~4–12MB
~136K SLoC