LSP

A language server protocol built with GO for educational purposes.

( Check LSP specification for more information.)

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Every progress will be tagged as checkpoints. Every tag will have a different README, more detailed explanation for each checkpoint. To be updated contents of the checkpoints:

Checkpoint 1

• Basic DecodeMessage function
• Basic EncodeMessage function
• Basic Split function for the logger
• Basic tests for the functions above
• Basic Logger function
• Starting Stdin scanner in main, with no-op handleMessage function

Checkpoint 2: <-- You are here

• Recieve basic messages from the lsp client and log them
• Decoding the initialize
• Initialize response
• Text Document Synchronization

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Checkpoint 2

1- Basic logging when msg recieved from lsp client

// main.go
func handleMessage(logger *log.Logger, msg any) {
	logger.Println(msg)
}

Starting the LSP from Neovim

in some nvim lua file:

Example below, attaches the lsp client when buffer has the type 'markdown'.
go build main.go should be called, and used it's path for the cmd

--- add this to somewhere with autocmds
local client = vim.lsp.start_client({
	name = "kaandesu/LSP",
	cmd = { "path/to/the/build/LSP/main" },
	filetypes = { "markdown" },
})
if not client then
	vim.notify("there is something wrong with the client")
end
vim.api.nvim_create_autocmd("FileType", {
	pattern = { "md", "markdown" },
	callback = function()
		if not client then
			vim.notify("there is something wrong with the client")
			return
		end
		vim.notify("custom lsp attached!")
		vim.lsp.buf_attach_client(0, client)
	end,
})

About Server Lifecycle - specs

1- Initialize Request:

• The initialize request is sent as the first request from the client to the server.

• Server is not allowed to send any requests or notifications to the client until it has responded with an InitializeResult

• initialize request may only be sent once

• Afterwards, LSP shall respond with a InitializeResult

NEXT:

• TBD

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Honorable Mentions

• tjdevries/educationalsp
• Brazil