Klaussacklock

Based on game build 714014 | Last updated: 2026-03-03

Overview

KlausSackLock enables customizable key-based unlocking logic for entities (specifically designed for Klaus sack locks). It associates a callback function (onusekeyfn) with the lock and executes it when UseKey is called, handling key validation and optional consumption via the stackable component. The component automatically adds and removes the klaussacklock tag on the entity to identify its presence.

Usage example

local inst = CreateEntity()
inst:AddComponent("klaussacklock")

inst.components.klaussacklock:SetOnUseKey(function(lock_inst, key, doer)
    if key.prefab == "klauskey" then
        return true, nil, true -- success, no error message, consume key
    end
    return false, "Does not fit", false -- failure, error message, do not consume
end)

-- Later, attempt to use a key:
local success, msg = inst.components.klaussacklock:UseKey(some_key, some_actor)

Dependencies & tags

Components used: stackable (read via key.components.stackable for key removal) Tags: Adds klaussacklock; removes klaussacklock on component removal.

Properties

Property	Type	Default Value	Description
onusekeyfn	function|nil	nil	Callback function invoked by UseKey. Signature: fn(lock_inst, key, doer) → (success: boolean, fail_msg: string|nil, consumed: boolean).
inst	entity	nil	Reference to the entity this component is attached to (set in constructor).

Main functions

SetOnUseKey(onusekeyfn)

• Description: Sets the callback function that defines unlock logic when a key is used.
• Parameters: onusekeyfn (function|nil) — a function that accepts lock_inst, key, and doer and returns three values: success (boolean), optional fail_msg (string|nil), and consumed (boolean).
• Returns: Nothing.

UseKey(key, doer)

• Description: Attempts to unlock the lock using the provided key, invoking the configured onusekeyfn. Handles key validation and removal if consumed is true.
• Parameters: key (entity|nil) — the key entity to attempt unlocking; doer (entity) — the actor attempting the unlock.
• Returns: true on success; false, fail_msg on failure (with optional message).
• Error states: Returns false immediately if key is nil, key:IsValid() is false, or onusekeyfn is nil.

Events & listeners

None identified.

Key behavior notes

• The component does not manage keys automatically beyond calling UseKey; it relies entirely on the onusekeyfn callback for business logic.
• Key removal is automatic if onusekeyfn returns consumed = true. For stackable keys, stackable:Get():Remove() is used to safely decrement and remove one unit.
• The klaussacklock tag is essential for identification (e.g., via inst:HasTag("klaussacklock")) and must not be manually removed by mods.