@Test
public void testInnerMap() throws Exception {

    Marshaller marshaller = new CsvMarshaller();
    Map<String, Object> map = new HashMap<>();
    map.put(EventConstants.TIMESTAMP, EXPECTED_TIMESTAMP);
    map.put("test", "test");
    Map<String, Object> inner = new HashMap<>();
    inner.put("other", "other");
    map.put("inner", inner);
    String marshalled = marshaller.marshal(new Event(EXPECTED_TOPIC, map));
    System.out.println(marshalled);
    Assert.assertEquals("test=test,inner={other=other},timestamp=1454428780634,event.topics=testTopic", marshalled);
}