lsp
An implementation of the Language Server Protocol written in Crystal.
This shard is a partial implementation of the Language Server Protocol. It contains json mappings to the data structures and messages as well as a fully working server implementation.
The code has originally been written for the crystalline tool and is now extracted here.
Installation
-
Add the dependency to your
shard.yml
:dependencies: lsp: github: elbywan/crystal-lsp
-
Run
shards install
Usage
require "lsp/server"
# Declare the server capabilities
# See: https://microsoft.github.io/language-server-protocol/specifications/lsp/3.17/specification/#capabilities
server_capabilities = LSP::ServerCapabilities.new(
# ...
)
# STDIN and STDOUT are used by default, but you can pass any IO.
server = LSP::Server.new(STDIN, STDOUT, server_capabilities)
# A Controller is a class or struct that responds to client events.
# Example: https://github.com/elbywan/crystalline/blob/master/src/crystalline/controller.cr
server.start(Controller.new)
struct Controller
# Called just after receiving the "initialize" request
def on_init(init_params : LSP::InitializeParams) : Nil
# …
end
# Called after the handshake is complete and before listening for requests and notifications
def when_ready : Nil
# …
end
# Called when the client sends a request (https://microsoft.github.io/language-server-protocol/specifications/specification-3-16/#requestMessage)
def on_request(message : LSP::RequestMessage)
# …
end
# Called when the client sends a notification (https://microsoft.github.io/language-server-protocol/specifications/specification-3-16/#notificationMessage)
def on_notification(message : LSP::NotificationMessage) : Nil
# …
end
# Called when the client sends a response (https://microsoft.github.io/language-server-protocol/specifications/specification-3-16/#responseMessage)
def on_response(message : LSP::ResponseMessage, original_message : LSP::RequestMessage?) : Nil
# …
end
end
Contributing
- Fork it (https://github.com/elbywan/lsp/fork)
- Create your feature branch (
git checkout -b my-new-feature
) - Commit your changes (
git commit -am 'Add some feature'
) - Push to the branch (
git push origin my-new-feature
) - Create a new Pull Request
Contributors
- Julien Elbaz - creator and maintainer