Ns LSP

ns lsp command implements language server protocol. It uses stdin/stdout as JSON-RPC2 medium.

The LSP can be used by various editors and IDEs. Notably fn-vscode extension plumbs this LSP into VSCode.

The LSP is implemented inside the ns binary to make sure that it editor integrations behave 100% consistent with the command line tools.

References

• Upstream tracking issue https://github.com/cue-lang/cue/issues/142
• LSP Specification https://microsoft.github.io/language-server-protocol/specifications/lsp/3.17/specification/
• Cue Language specification https://cuelang.org/docs/references/spec/

Related work

• Cue LSP draft implementation https://github.com/galli-leo/cue-lsp-server/
• Go LSP framework https://github.com/go-language-server/jsonrpc2
• Go LSP type definitions https://github.com/sourcegraph/go-lsp/
• Another Go LSP framework https://github.com/TobiasYin/go-lsp/
• Private JSONRPC implementation https://pkg.go.dev/golang.org/x/tools/internal/jsonrpc2

Examples

• VSCode CUE syntax https://github.com/ngkcl/vscode-cuelang
• Abandoned 3p Golang LSP https://github.com/sourcegraph/go-langserver/blob/master/langserver/handler.go
• VSCode->Gopls integration https://github.com/golang/vscode-go/blob/master/src/language/goLanguageServer.ts
• VSCode LSP sample https://github.com/microsoft/vscode-extension-samples/tree/main/lsp-sample/