Mod API Reference

This explains how to use Warzone's mod API and links to the documentation for each object type.

Types

When writing a mod, you'll encounter variables/objects of three basic types:

  • Primitives: strings, numbers, booleans, etc.
  • Tables: collections of key/value pairs. A table is a lot like a hashmap or dictionary in other languages. Note that in Warzone, the key of a table will always be either a string or an integer. Some places in this reference will refer to Arrays which are just tables with numeric keys starting at 1.
  • Proxy objects: Discussed in the next section.

Proxy Objects

A proxy object proxies information back and forth between your mod and Warzone. You can tell if an object is a proxy object by looking for a proxyType field. All proxy objects always have the following fields:

  • proxyType: A string identifying the type of proxy object.
  • readOnly: False if you're allowed to make changes to this proxy object, or true if it's read-only.
  • readableKeys: An array containing all fields you're allowed to read from this object.
  • writableKeys: An array containing all fields you're allowed to change on this object if readOnly is False.

To read a field, simply read it like a property: obj.field. Similarly, to write to a proxy object, just assign to that field: obj.field = newVal.

Here's a handy function you can include in your mod to print out everything on a proxy object:

function PrintProxyInfo(obj)
    print('type=' .. obj.proxyType .. ' readOnly=' .. tostring(obj.readonly) .. ' readableKeys=' .. table.concat(obj.readableKeys, ',') .. ' writableKeys=' .. table.concat(obj.writableKeys, ','));
end

Writing Tables

If a writable Warzone proxy object exposes a table, and you wish to make changes to that table, you must assign the table back to the proxy object. For example, assume you have a GameStanding object named standing which exposes the Cards table, and you want to add something at index 9:

 standing.Cards[9] = something  --WRONG!

This code won't work since the proxy object isn't having anything assigned to it. Proxy objects are only aware of changes when something is directly assigned into them. To make this work, you must assign the table into the proxy object's field:

 local cards = standing.Cards
 cards[9] = something
 standing.Cards = cards; --Right

Note: If you use lua's type function, proxy objects will identify themselves as tables. However, that should be considered an implementation detail. For the purposes of this wiki, proxy objects aren't considered tables.

API Reference

Newer API features

Some features were introduced after the first version of the Mod API framework and should be checked for using IsVersionOrHigher:

Version Features
5.26 Use ServerGame.SetPlayerResource in Server_StartGame
5.24.2 CustomSpecialUnit.Health
5.24.1 WL.TickCount

CustomSpecialUnit.CombatOrder
5.22.2 Boss1.CombatOrder

Boss2.CombatOrder

Boss3.CombatOrder

Boss4.CombatOrder

Commander.CombatOrder

CustomSpecialUnitBuilder.Health
5.22 GameOrderCustom.OccursInPhaseOpt

TerritoryModification.RemoveSpecialUnitsOpt
5.21 New hook: Client_PresentCommercePurchaseUI

ClientGame.HighlightTerritories

ClientGame.CreateLocatorCircle

UI.IsDestroyed

WL.CancelClickIntercept

CustomSpecialUnit

GameOrderEventResult.CardInstancesCreated

GameOrderEvent.JumpToActionSpotOpt
5.20 Setting TerritoryStanding.OwnerPlayerID to WL.PlayerID.AvailableForDistribution

GameOrderEvent.AddResourceOpt

GameOrderEvent.AddCardPiecesOpt

GameOrderEvent.RemoveWholeCardsOpt

TerritoryModification.AddArmies

TerritoryModification.AddStructuresOpt
5.17 Using argument two of addNewOrder in Server_AdvanceTurn_Order

IncomeMod

GameOrderEvent.IncomeMods

UI.InterceptNextTerritoryClick

UI.InterceptNextBonusLinkClick

WL.StructureType.Arena

WL.StructureType.ArmyCache

WL.StructureType.ArmyCamp

WL.StructureType.Attack

WL.StructureType.Crafter

WL.StructureType.DigSite

WL.StructureType.Draft

WL.StructureType.Hospital

WL.StructureType.Market

WL.StructureType.MercenaryCamp

WL.StructureType.Mine

WL.StructureType.MoneyCache

WL.StructureType.Mortar

WL.StructureType.Power

WL.StructureType.Recipe

WL.StructureType.ResourceCache

WL.StructureType.Smelter

There is a chance that a player has a version of the app that pre-dates the introduction of the IsVersionOrHigher function. Many features were added after the first version of the Mod API Framework, but before the introduction of the function:

Version Features
Up to 4.14.2 Various bug fixes / performance enhancements relating to mods. No other changes made to mods API framework until version 5.17.
3.20.2 Mod support for commerce games (commerce added in 3.20.0)
3.19.3 Data storage

GamePlayer.Income

Game.SendGameCustomMessage

Server_GameCustomMessage

Client_GameRefresh

Client_PresentMenuUI

Game.CreateDialog

Bug fixes for GameOrderPlayCard, Armies.Add, Armies.Subtract
3.19.2 GameOrderCustom

UI.Destroy

UI.PromptFromList

UI.
3.18.2 Moved all WarLight mod classes into the global "WL" namespace. For example, to create an Armies object instead of just saying "Armies()", you now say WL.Armies.Create()
3.18.0 Mods added