NPE occurs when the pkFieldName is not defined on the cacheTypeMap property

The following NPE occurs when the pkFieldName is not defined on the cacheTypeMap property:

19:11:34,107 WARN [org.teiid.RUNTIME] (teiid-async-threads - 4) TEIID50036 VDB People.1 model "People" metadata failed to load. Reason:java.lang.

NullPointerException: java.lang.NullPointerException
at org.teiid.translator.infinispan.dsl.metadata.ProtobufMetadataProcessor.createRootTable(ProtobufMetadataProcessor.java:186)
at org.teiid.translator.infinispan.dsl.metadata.ProtobufMetadataProcessor.process(ProtobufMetadataProcessor.java:101)
at org.teiid.translator.infinispan.dsl.metadata.ProtobufMetadataProcessor.process(ProtobufMetadataProcessor.java:78)
at org.teiid.translator.ExecutionFactory.getMetadata(ExecutionFactory.java:950)
at org.teiid.query.metadata.NativeMetadataRepository.getMetadata(NativeMetadataRepository.java:96)
at org.teiid.query.metadata.NativeMetadataRepository.loadMetadata(NativeMetadataRepository.java:62)
at org.teiid.query.metadata.ChainingMetadataRepository.loadMetadata(ChainingMetadataRepository.java:55)
at org.teiid.jboss.VDBService$6.run(VDBService.java:395)
at org.teiid.jboss.VDBService$7.run(VDBService.java:446)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142) [rt.jar:1.8.0_111]
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617) [rt.jar:1.8.0_111]
at java.lang.Thread.run(Thread.java:745) [rt.jar:1.8.0_111]
at org.jboss.threads.JBossThread.run(JBossThread.java:122)