#component #events #client #repository #tokio #info #ccanvas

libccanvas

Utility for creating ccanvas components

3 unstable releases

0.2.0 Feb 19, 2024
0.1.1 Jan 20, 2024
0.1.0 Jan 14, 2024

#62 in #info

36 downloads per month

AGPL-3.0

170KB
5K SLoC

libccanvas

libccanvas makes easy for creating ccanvas components. For more information, see the ccanvas main repository.

Quickstart

Your component will be ran by the canvas when loaded, get started by creating a client with Client::new(ClientConfig::default()).

Please name your Rust project in format of ccanvas-XXXXX for identification.

#[tokio::main]
async fn main() {
    let mut client = Client::default();

    client.hidecursor();
    client.setchar(0, 0, 'H');
    client.setchar(1, 0, 'e');
    client.setchar(2, 0, 'l');
    client.setchar(3, 0, 'l');
    client.setchar(4, 0, 'o');
    client.setchar(5, 0, '!');

    // flush all changes
    client.renderall().await;


    // listen to all key presses
    client.subscribe(Subscription::AllKeyPresses).await;

    loop {
        let event = client.recv().await;
        // exit when 'q' is pressed
        if let EventVariant::Key(key) = event.get() {
            if key.code == KeyCode::Char('q') => {
                client.exit().await;
                break;
            }
        }
    }
}

Running the component

You will need ccanvas installed on your system.

  1. Install the component using cargo.
cargo install --path . # where `.` is your project directory
  1. Run ccanvas with the component loaded.
ccanvas hello ccanvas-hello # where `ccanvas-hello` is the command to run your component

You can find more examples of advance usage in /examples.

Implementation details

This is not just ccanvas bindings, here are things Client does under the hood to simplify developer ergonomics.

Confirm receiving events

When the server (from now on I will refer to the ccanvas server as just the server) pass an event to the client, it expects the client to confirm that it has received the event. And whether the event should be passed to other components.

  • A confirmation is automatically sent when an Event goes out of scope.
  • You can manually trigger this behaviour using Event.done(true) as well.

Handling responses

To preserve the order of requests, a client request will await until the server respond with a confirmation of the task being completed.

Auto self destruct

When Client goes out of scope, it will automatically call drop of self - thus removing it from the ccanvas session, avoiding the situation of a "ghost component".

Features

Feel free to add implementation of your own API/bindings/functionalities to this crate under a non-default feature gate. Check src/features for more info.

Dependencies

~3–15MB
~125K SLoC