#rpc #xi #json-rpc #front-end #client-send

xrl

Xi Rpc Lib - Tokio based implementation of the RPC used in the Xi editor

9 releases

0.0.9 Dec 27, 2020
0.0.8 Jul 25, 2019
0.0.7 Jun 16, 2019
0.0.5 Mar 12, 2018
0.0.1 Sep 29, 2017

#249 in Text editors

45 downloads per month

Custom license

110KB
2.5K SLoC

XRL (Xi Rpc Lib) is an implementation of a client for Xi RPC. It is used to build xi-tui.

It is still work in progress, but the major features are already in place.


lib.rs:

xrl is a Tokio based library to build clients for the Xi editor. The challenge with Xi RPC is that endpoints are both client (sending requests/notifications) and server (handling incoming requests/notifications).

extern crate futures;
extern crate tokio;
extern crate xrl;

use futures::{future, Future, Stream};
use xrl::*;

// Type that represent a `xi-core` peer. It implements `Frontend`,
// which means it can handle notifications and requests from
// `xi-core`.
#[allow(dead_code)]
struct MyFrontend {
    // This is not actually used in this example, but if we wanted to
    // our frontend could use a `Client` so that it could send
    // requests and notifications to `xi-core`, instead of just
    // handling incoming messages.
    client: Client,
}

// Implement how our client handles notifications & requests from the core.
impl Frontend for MyFrontend {
    type NotificationResult = Result<(), ()>;
    fn handle_notification(&mut self, notification: XiNotification) -> Self::NotificationResult {
        use XiNotification::*;
        match notification {
            Update(update) => println!("received `update` from Xi core:\n{:?}", update),
            ScrollTo(scroll) => println!("received `scroll_to` from Xi core:\n{:?}", scroll),
            DefStyle(style) => println!("received `def_style` from Xi core:\n{:?}", style),
            AvailablePlugins(plugins) => {
                println!("received `available_plugins` from Xi core:\n{:?}", plugins)
            }
            UpdateCmds(cmds) => println!("received `update_cmds` from Xi core:\n{:?}", cmds),
            PluginStarted(plugin) => {
                println!("received `plugin_started` from Xi core:\n{:?}", plugin)
            }
            PluginStoped(plugin) => {
                println!("received `plugin_stoped` from Xi core:\n{:?}", plugin)
            }
            ConfigChanged(config) => {
                println!("received `config_changed` from Xi core:\n{:?}", config)
            }
            ThemeChanged(theme) => println!("received `theme_changed` from Xi core:\n{:?}", theme),
            Alert(alert) => println!("received `alert` from Xi core:\n{:?}", alert),
            AvailableThemes(themes) => {
                println!("received `available_themes` from Xi core:\n{:?}", themes)
            }
            FindStatus(status) => println!("received `find_status` from Xi core:\n{:?}", status),
            ReplaceStatus(status) => {
                println!("received `replace_status` from Xi core:\n{:?}", status)
            }
            AvailableLanguages(langs) => {
                println!("received `available_languages` from Xi core:\n{:?}", langs)
            }
            LanguageChanged(lang) => {
                println!("received `language_changed` from Xi core:\n{:?}", lang)
            }
        }
        Ok(())
    }

    type MeasureWidthResult = Result<Vec<Vec<f32>>, ()>;
    // we don't actually use the `request` argument in this example,
    // hence the attribute.
    #[allow(unused_variables)]
    fn handle_measure_width(&mut self, request: MeasureWidth) -> Self::MeasureWidthResult {
        Ok(Vec::new())
    }
}

struct MyFrontendBuilder;

impl FrontendBuilder for MyFrontendBuilder {
    type Frontend = MyFrontend;
    fn build(self, client: Client) -> Self::Frontend {
        MyFrontend { client }
    }
}

fn init_xrl() {
    tokio::run(future::lazy(move || {
        // spawn Xi core
        let (client, core_stderr) = spawn("xi-core", MyFrontendBuilder {}).unwrap();

        // start logging Xi core's stderr
        tokio::spawn(
            core_stderr
                .for_each(|msg| {
                    println!("xi-core stderr: {}", msg);
                    Ok(())
                })
                .map_err(|_| ()),
        );

        let client_clone = client.clone();
        client
            // Xi core expects the first notification to be
            // "client_started"
            .client_started(None, None)
            .map_err(|e| eprintln!("failed to send \"client_started\": {:?}", e))
            .and_then(move |_| {
                let client = client_clone.clone();
                client
                    .new_view(None)
                    .map(|view_name| println!("opened new view: {}", view_name))
                    .map_err(|e| eprintln!("failed to open a new view: {:?}", e))
                    .and_then(move |_| {
                        // Forces to shut down the Xi-RPC
                        // endoint. Otherwise, this example would keep
                        // running until the xi-core process
                        // terminates.
                        println!("shutting down");
                        client_clone.shutdown();
                        Ok(())
                    })
            })
    }));
}

Dependencies

~9–17MB
~200K SLoC