Cannot configure Dynamic Data Lists Display portlet to use a non-default Display Template

• Type: Regression Bug
• Status: Closed
• Resolution: Fixed
• Affects Version/s: Master
• Fix Version/s: 7.0.0 DXP FP23, 7.0.X EE, 7.0.4 CE GA5, 7.1.X, Master
• Component/s: Dynamic Data Lists, Dynamic Data Lists > Display, Dynamic Data Mapping > Template Editor
• Labels:
  • QA-NF
  • fw_test_needed
  • liferay-digital-enterprise-70-sp5
  • liferay-fixpack-de-23-7010
• Branch Version/s:
  7.0.x
• Backported to Branch:
  Committed
• Story Points: 1.25
• Fix Priority: 4
• Git Pull Request: https://github.com/brianchandotcom/liferay-portal/pull/48694

Trying to use a custom Display Template for the Dynamic Data Lists Display portlet will fail to render. This is due to the DDLDisplayTemplateHandler not being found in the registry of TemplateHandlers.

Steps to reproduce:

1. From Content -> Dynamic Data Lists, create a new Data Definition
2. For the new Data Definition, create a Display Template
3. Add a new Dynamic Data List based on the new Data Definition
4. On the Liferay home page, add a Dynamic Data Lists Display portlet
5. Select the list created in step 3 to display
6. Exit to the page, then go to the portlet's configuration
7. Under "Optional Configuration," change the Display Template to the Display Template created in step 2
8. Save the configuration and exit back to the page (or refresh)
   Expected result: the Display Template is loaded and rendered as expected
   Actual result: the Display Template fails to load, and an error is thrown in the console

Reproduced in master: 44fbba759fa8cc88faef2406168d9967eec810dc

The error shown in the console is like the following:

15:48:58,515 ERROR [http-nio-8080-exec-9][IncludeTag:128] Current URL /web/guest/home generates exception: java.lang.NullPointerException
java.lang.NullPointerException
	at com.liferay.dynamic.data.lists.web.internal.template.DDLDisplayTemplateTransformer.transform(DDLDisplayTemplateTransformer.java:99)
	at org.apache.jsp.view_005ftemplate_005frecords_jsp._jspService(view_005ftemplate_005frecords_jsp:327)
	at org.apache.jasper.runtime.HttpJspBase.service(HttpJspBase.java:111)
	at javax.servlet.http.HttpServlet.service(HttpServlet.java:729)
	at org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:411)
	at org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:473)
	at org.apache.jasper.servlet.JspServlet.service(JspServlet.java:377)
	at javax.servlet.http.HttpServlet.service(HttpServlet.java:729)
	at com.liferay.portal.osgi.web.servlet.jsp.compiler.JspServlet.service(JspServlet.java:413)
	at com.liferay.portal.osgi.web.servlet.jsp.compiler.JspServlet.service(JspServlet.java:424)
	at org.eclipse.equinox.http.servlet.internal.registration.EndpointRegistration.service(EndpointRegistration.java:153)
	at org.eclipse.equinox.http.servlet.internal.servlet.ResponseStateHandler.processRequest(ResponseStateHandler.java:62)
	at org.eclipse.equinox.http.servlet.internal.context.DispatchTargets.doDispatch(DispatchTargets.java:117)
	at org.eclipse.equinox.http.servlet.internal.servlet.RequestDispatcherAdaptor.include(RequestDispatcherAdaptor.java:48)
	at com.liferay.portal.servlet.DirectServletPathRegisterDispatcher.include(DirectServletPathRegisterDispatcher.java:67)
	at com.liferay.portal.servlet.ClassLoaderRequestDispatcherWrapper.doDispatch(ClassLoaderRequestDispatcherWrapper.java:78)
	at com.liferay.portal.servlet.ClassLoaderRequestDispatcherWrapper.include(ClassLoaderRequestDispatcherWrapper.java:53)
	at com.liferay.taglib.util.IncludeTag.includePage(IncludeTag.java:372)
	at com.liferay.taglib.util.IncludeTag.include(IncludeTag.java:349)
	at com.liferay.taglib.util.IncludeTag.doInclude(IncludeTag.java:202)