HTTP Server Lua Demo

Use this skill when the user wants a simple Lua HTTP server demo page, a Hello World web UI, or a browser switch that calls back into Lua.

Run exactly one bundled Lua script asynchronously with the Lua script execution capability.

If script execution returns an error, report that error directly to the user.

Script Args Schema

{
  "type": "object",
  "properties": {
    "app_id": {
      "type": "string",
      "description": "Optional URL-safe app id. Defaults to lua_demo."
    },
    "web_root": {
      "type": "string",
      "description": "Optional absolute directory for static web files. Defaults to {CUR_SKILL_DIR}/assets."
    }
  }
}

Tool Call Inputs

Default action:

{
  "path": "{CUR_SKILL_DIR}/scripts/lua_demo_server.lua",
  "args": {
    "app_id": "lua_demo",
    "web_root": "{CUR_SKILL_DIR}/assets"
  }
}

Recommended Flow

Run the bundled Lua script asynchronously so the HTTP callbacks stay alive:

• Script: {CUR_SKILL_DIR}/scripts/lua_demo_server.lua
• Capability: lua_run_script_async
• Timeout: 0
• Name: http_server_lua_demo
• Exclusive: http_server_lua_demo
• Replace: true
• Args: optional object

Example args:

{
  "app_id": "lua_demo",
  "web_root": "{CUR_SKILL_DIR}/assets"
}

After the script starts, open:

/lua/lua_demo/

Keep the trailing slash. Opening /lua/lua_demo without the trailing slash can make browsers resolve relative assets under /lua/ instead of /lua/lua_demo/. The bundled page uses absolute asset paths for the default lua_demo app id; if app_id is changed, update the HTML asset URLs or keep using the exact trailing-slash URL.

Behavior

The script mounts the bundled assets/ directory with http_server and registers:

• GET /api/lua/lua_demo/state
• POST /api/lua/lua_demo/toggle

The page displays "Hello World" and a switch. When the switch changes, the browser posts the new state to Lua, and Lua logs:

[http_server_lua_demo] {"enabled":true,"event":"switch_toggled"}

JSON Usage

The script uses lua_module_json to decode the browser POST body instead of matching JSON text manually. The /toggle handler accepts:

{
  "enabled": true
}

Lua parses the request body with:

local data = json.decode(req.body)

The script also uses json.encode() to print structured switch events.

Stop the async Lua job when the demo page should be closed.