Crate xrl

Expand description

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(())
                    })
            })
    }));
}

Structs§

Alert
AvailableLanguages
AvailablePlugins
AvailableThemes
Client: A client to send notifications and request to xi-core.
ConfigChanged
ConfigChanges
CoreStderr: A stream of Xi core stderr lines
FindStatus
LanguageChanged
Line
LineCache: Line cache struct to work with xi update protocol.
MeasureWidth
Operation
PluginStarted
PluginStoped
Position
Query
ReplaceStatus
ScrollTo
Status
Style
StyleDef
ThemeChanged
Update
UpdateCmds
ViewId

Enums§

ClientError
ModifySelection
OperationType
ServerError
XiNotification: Represents all possible RPC messages recieved from xi-core.

Traits§

Frontend: The Frontend trait must be implemented by clients. It defines how the client handles notifications and requests coming from xi-core.
FrontendBuilder: A trait to build a type that implements Frontend.
IntoStaticFuture: Class of types which can be converted into a future. This trait is only differs from futures::future::IntoFuture in that the returned future has the 'static lifetime.

Functions§

spawn: Start Xi core, and spawn an RPC client on the current tokio executor.
spawn_command: Same as spawn but accepts an arbitrary std::process::Command.

Type Aliases§