private MetaProperties createProps(final Meta parent, final String feedName, final String typeName) {
        final long now = System.currentTimeMillis();
        return MetaProperties.builder()
                .parent(parent)
                .feedName(feedName)
                .typeName(typeName)
                .createMs(now)
                .build();
    }
Make sure that it copes with a map not being in an early stream but is in a later one.
stroom-app/src/test/java/stroom/pipeline/refdata/TestReferenceData.java