Custom events

Custom lsp requests or notifications can be registered using the register_request or register_notification methods of Session.

Both methods accept a callback as the second parameter, which is executed to fulfill the event.

The callback methods take two parameters:

• Session: The global state of the server.
• Parameters: The request or notification parameters.

To add a request, implement the Request trait from lsp_types:

pub struct GetWorkspaceFilesUris {}

impl Request for GetWorkspaceFilesUris {
    type Params = (); // Parameters for the request
    type Result = Vec<String>; // Expected response type
    const METHOD: &'static str = "custom/GetWorkspaceFilesUris"; // Method name used in the request
}

Similarly, to add a notification, implement the Notification trait instead of Request.

Example: Registering a Custom Request

use auto_lsp::lsp_server::Connection;
use auto_lsp::python::PYTHON_PARSERS;
use auto_lsp::server::{InitOptions, LspOptions, Session};
use auto_lsp::lsp_types::request::Request;

pub struct GetWorkspaceFilesUris {}

impl Request for GetWorkspaceFilesUris {
    type Params = ();
    type Result = Vec<String>;
    const METHOD: &'static str = "custom/GetWorkspaceFilesUris";
}

fn main() -> Result<(), Box<dyn Error + Sync + Send>> {
    let (connection, io_threads) = Connection::stdio();

    let mut session = Session::create(
        InitOptions {
            parsers: &PYTHON_PARSERS,
            lsp_options: LspOptions {
                ..Default::default()
            },
        },
        connection,
    )?;

    session.register_request::<GetWorkspaceFilesUris, _>(|session, _| {
        let guard = session.get_workspace();
        Ok(guard.roots.iter().map(|uri| uri.0.to_string()).collect())
    });

    // Run the server and wait for both threads to terminate (typically triggered by an LSP Exit event).
    session.main_loop()?;
    io_threads.join()?;

    // Shut down gracefully.
    eprintln!("Shutting down server");
    Ok(())
}