Prerequisite for this guide, you must install the package DAM for Sitecore JSS-11.1.zip
If you are using the Sitecore Layout Services /sitecore/api/layout/render/[config]?item=[path]&sc_lang=[language]&sc_apikey=[key]
The connector comes with a fieldserializer for each of the 3 custom field types: asset, assetlink and assetlist.
<?xml version="1.0" encoding="utf-8" ?>
<configuration xmlns:patch="http://www.sitecore.net/xmlconfig/" xmlns:role="http://www.sitecore.net/xmlconfig/role/" xmlns:search="http://www.sitecore.net/xmlconfig/search/">
<sitecore>
<pipelines>
<group groupName="layoutService">
<pipelines>
<getFieldSerializer performanceCritical="true">
<processor patch:before="processor[@type='Sitecore.LayoutService.Serialization.Pipelines.GetFieldSerializer.GetDefaultFieldSerializer, Sitecore.LayoutService']" type="DFS.JSS.Serializers.GetAssetFieldSerializer, DFS.JSS" resolve="true">
<FieldTypes hint="list">
<fieldType id="1">Asset</fieldType>
</FieldTypes>
</processor>
<processor patch:before="processor[@type='Sitecore.LayoutService.Serialization.Pipelines.GetFieldSerializer.GetDefaultFieldSerializer, Sitecore.LayoutService']" type="DFS.JSS.Serializers.GetAssetLinkFieldSerializer, DFS.JSS" resolve="true">
<FieldTypes hint="list">
<fieldType id="1">Assetlink</fieldType>
</FieldTypes>
</processor>
<processor patch:before="processor[@type='Sitecore.LayoutService.Serialization.Pipelines.GetFieldSerializer.GetDefaultFieldSerializer, Sitecore.LayoutService']" type="DFS.JSS.Serializers.GetAssetListFieldSerializer, DFS.JSS" resolve="true">
<FieldTypes hint="list">
<fieldType id="1">Assetlist</fieldType>
</FieldTypes>
</processor>
</getFieldSerializer>
</pipelines>
</group>
</pipelines>
</sitecore>
</configuration>