Scriptloader

This is a very simple track-script that just serves as a loader for scripts hosted online. The CSP API does not allow track scripts to load scripts via URL directly (unlike apps or server scripts, where you can simply pass a URL instead of a path), however we can go around this by loading the script (that we actually want) from within this script loader.

The advantage of this over a track-script directly built into the map is simply that it can be updated "on the fly", without the track author needing to ship a new version of their track with the updated script.

At the moment, the loaded script should not be able access ini settings or files on the players pc.

Info

Since this loader script takes in a URL, it only works if the player actually has an internet connection! Scripts are not stored locally.

Danger

Loading scripts from an online source can be dangerous. The user will never see the downloaded source and the code it downloads is just run as-is. While CSP has a lot of restrictions on what a track script is even allowed to do, a bad actor could always somehow try to take advantage of this.

Usage

Download the scriptloader lua from github, place it into your extension folder and add this to your ext_config.ini

[SCRIPT_...]
url='https://some.url.to/a.script'
SCRIPT='scriptloader.lua'

You can add this ini config as many times as you want with different URLs.

Important

Script Modifications and Function Naming

Externally loaded scripts can not execute their own script.update or script.update3D functions. The way this is solved is by returning the functions itself so that this loader script can call them. This is a really hacky workaround but it seems to work just fine. Scripts must be changed to return a table with either script.update and script.update3D or update and update3D as values. It is important that the function names used and returned MUST match. For example:

function script.update(dt)
end

function script.draw3D()
end

return {script.update, script.draw3D}
-- NOT return {update, draw3D}

function update(dt)
end

function draw3D()
end

return {update, draw3D}
-- NOT return {script.update, script.draw3D}

Warning

The first value has to be update or script.update, the second value has to be draw3D or script.draw3D. You can pass nil as value if you dont use one or the other function.

The automated solution

This loader script has an automated solution that may or may not work. It checks if a string along the lines of return {script.update, script.draw3D} exists and if not, automatically appends its own code that returns the correct table. It may fail at times because pattern matching in LUA is very limited - however, it worked fine in my testing.

To use it, add autofix=true to the script entry

[SCRIPT_...]
url='https://some.url.to/a.script'
autofix=true
SCRIPT='scriptloader.lua'