Charts - Export Charts are canvas based and can be exported as static images with client side api.

Chart as an Image
<p:chart type="line" value="#{chartView.lineModel1}" style="width:500px;height:300px" widgetVar="chart"/>
<p:commandButton type="button" value="Export" icon="ui-icon-extlink" onclick="exportChart()"/>

<p:dialog widgetVar="dlg" showEffect="fade" modal="true" header="Chart as an Image" resizable="false">
    <p:outputPanel id="output" layout="block" style="width:500px;height:300px"/>

<script type="text/javascript">
function exportChart() {
    //export image

    //show the dialog
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