Listener

Validated local and network event listeners

Listener

The listener module wraps FiveM event registration and validates arguments before your callback runs. It works with schemas from the validator module.

local listener = sure.getModule('listener')
local v = sure.getModule('validator')

Local events

listener
  :on('inventory:useItem', function(itemName, amount)
    print(('Use %sx %s'):format(amount, itemName))
  end)
  :expect(
    v.string().required(),
    v.integer().min(1)
  )

Network events

listener
  :onNet('shop:buy', function(itemName, amount)
    -- This callback only runs when both arguments pass validation.
  end)
  :expect(
    v.string().required(),
    v.integer().between(1, 100)
  )

API

on(eventName, callback) · function · required

Registers a local event through AddEventHandler.

onNet(eventName, callback) · function · required

Registers a network event through RegisterNetEvent.

expect(...validators) · function

Attaches validators to positional event arguments. Argument 1 is checked by validator 1, argument 2 by validator 2, and so on.

listenerMeta · table

on and onNet return a metadata table with expect(...) so the validation contract can be chained close to the callback.

A failed parameter validation prints an error and raises. Keep validators strict for trusted internal events and wrap external flows with server-side permission checks where needed.

Pattern

Client

client.lua

listener
  :onNet('sure:notify', function(message)
    lib.notify({ description = message })
  end)
  :expect(v.string().required())

Server

server.lua

listener
  :onNet('sure:claimReward', function(rewardId)
    local source = source
    -- Validate permissions before paying rewards.
  end)
  :expect(v.string().required())