XML Patching (XPath)

Part of the 7DTD Modding Knowledgebase. Covers the XPath patch system used by all Config/ XML files.

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Overview

7DTD mods don't replace vanilla XML files — they patch them. Each Config/*.xml file is an XPath patch document. The game merges patches from all mods at startup, then discards the patch files and uses the merged result.

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Basic Patch Operations

Append a child node

<configs>
    <append xpath="/blocks">
        <block name="myBlock">
            <property name="Class" value="MyBlock" />
        </block>
    </append>
</configs>

Set an attribute on an existing node

<configs>
    <set xpath="/blocks/block[@name='stone']/property[@name='MaxDamage']/@value">5000</set>
</configs>

Insert before a node

<configs>
    <insertBefore xpath="/blocks/block[@name='stone']">
        <block name="myBlock">...</block>
    </insertBefore>
</configs>

Remove a node

<configs>
    <remove xpath="/blocks/block[@name='stone']" />
</configs>

Works for any node type — confirmed working on vanilla window definitions and item/entity entries.

Set an attribute (alternative form)

<setattribute> modifies a named attribute on the matched element:

<configs>
    <setattribute xpath="/blocks/block[@name='stone']" name="MaxDamage">5000</setattribute>
</configs>

Equivalent to <set xpath=".../@attrName">value</set>, but more explicit.

Insert after a node

<configs>
    <insertAfter xpath="/blocks/block[@name='stone']">
        <block name="myBlock">...</block>
    </insertAfter>
</configs>

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Targeting Vanilla XUi

To add a window:

<configs>
    <append xpath="/windows">
        <window name="myWindow" ...>
            ...
        </window>
    </append>
</configs>

To add a window group to the default ruleset:

<configs>
    <append xpath="/xui/ruleset[@name='default']">
        <window_group name="myGroup" controller="MyGroupController">
            <window name="myWindow" />
        </window_group>
    </append>
</configs>

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Targeting Blocks

<configs>
    <append xpath="/blocks">
        <block name="PixelPaste">
            <property name="Class" value="PixelPaste" />
            <property name="Material" value="Mconcrete" />
            <!-- ... -->
        </block>
    </append>
</configs>

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Conditional Patching

Apply patches only when another mod is (or isn't) loaded:

<configs>
    <conditional>
        <if cond="mod_loaded('XRamosZUI')">
            <!-- Only applied if XRamosZUI is installed -->
            <set xpath="/xui/ruleset[@name='default']/@scale">1.245</set>
        </if>
    </conditional>

    <conditional>
        <if cond="not mod_loaded('OtherMod')">
            <!-- Only applied if OtherMod is NOT installed -->
        </if>
    </conditional>
</configs>

The mod name in mod_loaded() is the Name value from that mod's ModInfo.xml.

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Advanced XPath Selectors

<!-- Double-slash: recursive descent — match anywhere in tree -->
<remove xpath="//window[@name='windowFoo']" />

<!-- contains() — partial attribute match -->
<set xpath="//item_stack[contains(@controller, 'ItemStack')]/@tooltip">""</set>

<!-- Multiple attribute predicates -->
<set xpath="/items/item[@name='ammo9mmBullet']/property[@name='Stacknumber']/@value">500</set>

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Tips

• The xpath attribute is standard XPath 1.0
• Attribute selectors use [@name='value'] syntax
• Multiple operations can be in one file — list them all inside <configs>
• Patches are applied in load order; mod load order is not guaranteed unless using ModInfo.xml dependencies
• The same <remove> + <append> pattern works for replacing vanilla XUi windows, items, entity classes, etc.

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Sounds

Custom sounds go in Config/sounds.xml:

<configs>
    <append xpath="/SoundDataNode">
        <SoundDataNode name="MySoundName">
            <Noise ID="6" noise="250" time="3" heat_map_strength="5" />
            <AudioClip ClipName="#@modfolder:Resources/MySounds.unity3d?MySoundClip.wav" Loop="false" />
        </SoundDataNode>
    </append>
</configs>

• #@modfolder: resolves to the mod's install directory
• Audio must be inside a .unity3d asset bundle in the Resources/ folder
• heat_map_strength controls how much noise the sound generates (attracts zombies)
• Loop="true" for ambient/looping sounds

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Targeting Items

New items are normally appended to /items:

<configs>
    <append xpath="/items">
        <item name="myCustomItem">
            <property name="Meshfile" value="Items/Misc/oilGP" />
            <property name="Stacknumber" value="64" />
        </item>
    </append>
</configs>

To edit a property on an existing item, target the item by internal name and then the property by name:

<configs>
    <set xpath="/items/item[@name='resourceWood']/property[@name='Stacknumber']/@value">1000</set>
</configs>

Use /items/item[@name='itemName'] for item selectors. Use /blocks/block[@name='blockName'] for block selectors. Do not mix the two: items live in items.xml, blocks live in blocks.xml, though placeable items may reference blocks through properties such as PlaceAsBlock.