Language server

The rules ship as a standalone language server, nestjs-doctor-lsp on npm. Any editor with an LSP client runs them, Neovim and Helix and Emacs among them. The VS Code extension is one such client, wrapping this same server.

The server loads the analysis engine from the project you open, so add it there:

npm install -D nestjs-doctor

The server itself needs no install. npx fetches it from npm on first run.

Every client spawns the same binary over stdio:

npx nestjs-doctor-lsp --stdio

It answers initialize with textDocumentSync: 1 and no other capability. There is no hover, no code action, and no formatting. It publishes diagnostics and nothing else.

Each diagnostic carries nestjs-doctor as its source and the rule id as its code. A schema finding has no line, so it lands on line 1 of the file that declares the entity.

Neovim 0.11 or newer reads this from init.lua:

vim.lsp.config("nestjs_doctor", {
	cmd = { "npx", "nestjs-doctor-lsp", "--stdio" },
	filetypes = { "typescript" },
	root_markers = { "package.json" },
})
 
vim.lsp.enable("nestjs_doctor")

root_markers decides which directory the client sends as rootUri, and that directory is the one the server scans. A client that sends neither rootUri nor the deprecated rootPath has nothing to scan and fails on the first attempt.

Editing without saving publishes nothing, because the server handles didSave and not didChange. Saves are debounced, and a save of anything other than a .ts file is ignored.

The watched-file row is what refreshes a dependency finding. The server never registers a watcher itself, so the client has to send workspace/didChangeWatchedFiles for **/package.json. A client that does not leaves every advisory finding as it was until the session restarts.

While starting, the server asks the client for the nestjsDoctor configuration section. The four settings are the ones the VS Code extension exposes, with the same defaults. Send them the way your client sends configuration, which in Neovim is the settings table on the server config.

A client that never answers the workspace/configuration request leaves the server waiting, and no scan runs. Answering with null is fine and the defaults apply.

When nestjs-doctor is missing from the project you opened, the server sends this warning and stops:

nestjs-doctor is not installed in this workspace. Run: npm install nestjs-doctor

A client that does not display server messages shows nothing at all, so check the install first when no diagnostics appear. Rule configuration comes from the project's nestjs-doctor.config.json, the same file the CLI reads. See Configuration.