jlens-lsp

A language server (LSP) for JSONata expressions. Part of jlens.

• Completion of fields from a JSON Schema of the input documents, of variables, and of built-in and host functions.
• Diagnostics: syntax errors, annotation problems, and fields the schema does not have ("did you mean").
• Hover and signature help.

Editors run it as jlens lsp (cargo install jlens-cli). A jlens.json at the root of each workspace folder says which schema, variables and host functions apply to which files:

{
  "rules/**/*.jsonata": {
    "schema": "schemas/order.schema.json",
    "variables": {"minimum": {"type": "number"}},
    "functions": [{"name": "shipping", "signature": "<ns:n>", "summary": "Shipping cost"}]
  }
}

To embed the server, run jlens_lsp::run on an lsp_server::Connection. The editors guide of the jlens book covers the configuration and the setup of Neovim, Helix and Emacs.