galaxy/config/plugins/visualizations/example/static/example.xml

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE visualization SYSTEM "../../visualization.dtd">
<visualization name="Minimal Example" hidden="true">
    <description>Welcome to the Minimal JS-Based Example Plugin.</description>
    <data_sources>
        <data_source>
            <model_class>HistoryDatasetAssociation</model_class>
            <test type="isinstance" test_attr="datatype" result_type="datatype">tabular.Tabular</test>
            <to_param param_attr="id">dataset_id</to_param>
        </data_source>
    </data_sources>
    <params>
        <param type="dataset" var_name_in_template="hda" required="true">dataset_id</param>
    </params>
    <entry_point entry_point_type="script" src="script.js" />
    <settings>
        <input>
            <name>setting_input</name>
            <help>setting help</help>
            <type>setting_type</type>
        </input>
    </settings>
    <tracks>
        <input>
            <name>track_input</name>
            <help>track help</help>
            <type>track_type</type>
        </input>
    </tracks>
    <specs>
        <spec_name>spec_value</spec_name>
    </specs>
</visualization>