> For the complete documentation index, see [llms.txt](https://docs.tonic.ai/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.tonic.ai/app/api/quick-start-guide/tonic-api-generator-assignment/generator-api-reference/generator-api-ref-xml-mask.md).

# XML Mask (XmlMaskGenerator)

The [XML Mask](/app/generation/generators/generator-reference/xml-mask.md) generator runs a selected generator on values that match a user specified path expression.

## Link object structure <a href="#generator-api-xml-mask-link-object" id="generator-api-xml-mask-link-object"></a>

For the XML Mask generator, there is a link object for each path expression value to assign a sub-generator to.

The generator does not itself support consistency or differential privacy.

The `metadata` object is populated from the [`XmlMaskMetadata`](https://app.tonic.ai/apidocs/index.html#/models/XmlMaskMetadata) object. It includes:

* `pathExpression`, which is the expression that identifies the value to apply the sub-generator to.
* The `subGeneratorMetadata` object, which identifies and configures the sub-generator.

{% code overflow="wrap" %}

```json
{
  "schema": "string",
  "table": "string",
  "column": "string",
  "dataType": "string",  //MongoDB only
  "metadata": {
    "generatorId": "XmlMaskGenerator",
    "customValueProcessor": "string",  //If custom value processor applied
    "pathExpression": "string",
    "subGeneratorMetadata": {
      "presetId": "string",
      "generatorId": "string",
      //Metadata for the selected sub-generator
      "customValueProcessor": "string"  //If custom value processor applied to the sub-generator
    }
  }
}
```

{% endcode %}

## Example replacement <a href="#generator-api-xml-mask-replacement" id="generator-api-xml-mask-replacement"></a>

In the following example replacement for the XML Mask generator:

* The Name generator is assigned to the path expression `//view/item-descriptor//@display-name`. The value is in the format First Name Last Name (John Smith), and capitalization is not preserved. Consistency is disabled.
* The Constant generator is assigned to the path expression `//view//object-class`. The constant value is `object-class`.

```json
{
  "name": "xml_data",
  "schema": "public",
  "table": "xml_me",
  "links": [
    {
      "schema": "public",
      "table": "xml_me",
      "column": "xml_data",
      "metadata": {
        "generatorId": "XmlMaskGenerator",
        "presetId": "XmlMaskGenerator",
        "pathExpression": "//view/item-descriptor//@display-name",
        "subGeneratorMetadata": {
          "presetId": "NameGenerator",
          "generatorId": "NameGenerator",
          "nameType": "FirstThenLastName",
          "preserveCapitalization": false,
          "isConsistent": false
        }
      }
    },
    {
      "schema": "public",
      "table": "xml_me",
      "column": "xml_data",
      "metadata": {
        "generatorId": "XmlMaskGenerator",
        "presetId": "XmlMaskGenerator",
        "pathExpression": "//view//object-class",
        "subGeneratorMetadata": {
          "presetId": "ConstantGenerator",
          "generatorId": "ConstantGenerator",
          "constant": "object-class"
        }
      }
    }
  ]
}
```


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