Exports

Exports allow resources to share functions with other resources. The server example below uses ESX .

Defining Exports

Server Export


-- server.lua
exports('getPlayerData', function(source)
    local xPlayer = ESX.GetPlayerFromId(source)
    return xPlayer
end)

Client Export


-- client.lua
exports('showNotification', function(message)
    -- Show notification
end)

Consuming Exports

Server


local playerData = exports['myresource']:getPlayerData(source)

Client


exports['myresource']:showNotification('Hello!')

Namespacing

Use resource name as namespace:


-- Good
exports['qb-core']:GetPlayer(source)
 
-- Bad
exports:GetPlayer(source)

Identifying the Caller

Inside an export, GetInvokingResource() returns the name of the resource that called it. It returns nil when there is no invoking script runtime (native , source ). Use it to allow-list callers and to key per-caller state, then drop that state when the caller stops. Listening to onResourceStop for another resource’s name is reliable, because your own resource is still running. Cfx’s own chat resource uses this pattern for registerMessageHook.


-- server.lua (provider resource)
local allowedCallers = { ['my-shop'] = true }
local hooks = {}
 
exports('registerHook', function(fn)
    local caller = GetInvokingResource()
    if not caller or not allowedCallers[caller] then
        return false
    end
    hooks[caller] = fn
    return true
end)
 
AddEventHandler('onResourceStop', function(resourceName)
    -- Drop the registration of a caller that stopped
    hooks[resourceName] = nil
end)

Error Handling Patterns

Checking Export Availability

Before calling an export, check if the resource is started to avoid errors.


if GetResourceState('ox_inventory') == 'started' then
    local items = exports.ox_inventory:Items()
else
    print('ox_inventory is not started')
end

Protected Calls (pcall)

Use pcall when the export might fail internally or return unexpected data.


local success, result = pcall(function()
    return exports['myresource']:riskyOperation()
end)
 
if success then
    print('Result:', result)
else
    print('Export call failed:', result)
end

Versioning Strategies

When updating exports, maintain backward compatibility.

Strategy A: Argument Inspection

Check arguments inside the export to support multiple formats.


exports('giveItem', function(target, item, count)
    if type(target) == 'table' then
        -- Handle new object-style arguments
        count = target.count
        item = target.item
        target = target.source
    end
    -- ... implementation
end)

Strategy B: Versioned Names

Create new exports for breaking changes.


exports('giveItem', function(...) end) -- v1 (Deprecated)
exports('giveItem_v2', function(opts) end) -- v2

Testing Exports

Create a test suite script to verify your exports behave as expected.


-- tests.lua
CreateThread(function()
    Wait(1000) -- Wait for resources to load
 
    print('Testing exports...')
 
    local result = exports['myresource']:calculate(5, 5)
    assert(result == 10, 'Math export failed')
 
    print('Tests passed!')
end)

Documentation Standards

Document your exports clearly in your README or code comments so other developers know how to use them.


--- @export getBalance
--- Retreives the current bank balance for a player
--- @param source number The player server ID
--- @param accountType string "bank" or "cash"
--- @return number The balance, or 0 if not found
exports('getBalance', function(source, accountType)
    -- ...
end)

Best Practices

Use descriptive names: getUser vs get.
Return values: Always return something (even false or nil) to confirm execution.
Async consideration: Remember exports are synchronous. For heavy tasks, use callbacks or events.