Crate async_lsp

Asynchronous Language Server Protocol (LSP) framework based on tower.

See project README for a general overview.

This project is centered at a core service trait LspService for either Language Servers or Language Clients. The main loop driver MainLoop executes the service. The additional features, called middleware, are pluggable can be layered using the tower_layer abstraction. This crate defines several common middlewares for various mandatory or optional LSP functionalities, see their documentations for details.

• concurrency::Concurrency: Incoming request multiplexing and cancellation.
• panic::CatchUnwind: Turn panics into errors.
• tracing::Tracing: Logger spans with methods instrumenting handlers.
• server::Lifecycle: Server initialization, shutting down, and exit handling.
• client_monitor::ClientProcessMonitor: Client process monitor.
• router::Router: “Root” service to dispatch requests, notifications and events.

Users are free to select and layer middlewares to run a Language Server or Language Client. They can also implement their own middlewares for like timeout, metering, request transformation and etc.

Usages

There are two main ways to define a Router root service: one is via its builder API, and the other is to construct via implementing the omnitrait LanguageServer or LanguageClient for a state struct. The former is more flexible, while the latter has a more similar API as tower-lsp.

The examples for both builder-API and omnitrait, cross Language Server and Language Client, can be seen under examples directory.

Cargo features

• client-monitor: Client process monitor middleware client_monitor. Enabled by default.
• omni-trait: Mega traits of all standard requests and notifications, namely LanguageServer and LanguageClient. Enabled by default.
• stdio: Utilities to deal with pipe-like stdin/stdout communication channel for Language Servers. Enabled by default.
• tracing: Integration with crate tracing and the tracing middleware. Enabled by default.
• forward: Impl LspService for {Client,Server}Socket. This collides some method names but allows easy service forwarding. See examples/inspector.rs for a possible use case. Disabled by default.
• tokio: Enable compatible methods for tokio runtime. Disabled by default.

Re-exports

pub use lsp_types;

Modules

client_monitorclient-monitor

Stop the main loop when the Language Client process aborted unexpectedly.

concurrency

Incoming request multiplexing limits and cancellation.

panic

Catch panics of underlying handlers and turn them into error responses.

router

Dispatch requests and notifications to individual handlers.

server

Language Server lifecycle.

stdiostdio and Unix

Utilities to deal with stdin/stdout communication channel for Language Servers.

tracingtracing

Attach tracing::Spans over underlying handlers.

Structs

AnyEvent

A dynamic runtime event.

AnyNotification

A dynamic runtime LSP notification.

AnyRequest

A dynamic runtime LSP request.

ClientSocket

The socket for Language Server to communicate with the Language Client peer.

ErrorCode

A JSON-RPC error code.

MainLoop

Service main loop driver for either Language Servers or Language Clients.

ResponseError

The error object in case a request fails.

ServerSocket

The socket for Language Client to communicate with the Language Server peer.

Enums

Error

Possible errors.

Traits

LanguageClientomni-trait

The omnitrait defining all standard LSP requests and notifications supported by lsp_types for a Language Client.

LanguageServeromni-trait

The omnitrait defining all standard LSP requests and notifications supported by lsp_types for a Language Server.

LspService

The core service abstraction, representing either a Language Server or Language Client.

Type Aliases

RequestId

The identifier of requests and responses.

Result

A convenient type alias for Result with E = crate::Error.