@Test
public void testGetExtensionById() {

    final ExtensionEntity extension = metadataService.getExtensionById("e1");
    assertNotNull(extension);
    assertEquals("e1", extension.getId());
    assertEquals("org.apache.nifi.ExampleProcessor", extension.getName());
    assertEquals("{ \"name\" : \"org.apache.nifi.ExampleProcessor\", \"type\" : \"PROCESSOR\" }", extension.getContent());
    assertFalse(extension.getHasAdditionalDetails());
}