private void assertDataFeedRequestContent(final List<DataFeedRequest> dataFeedRequests,
                                              final List<String> expectedFiles) {
        dataFeedRequests.forEach(dataFeedRequest -> {
            for (int i = 0; i < dataFeedRequest.getDataFeedRequestItems().size(); i++) {
                final DataFeedRequestItem zipItem = dataFeedRequest.getDataFeedRequestItems().get(i);
                final String expectedName = expectedFiles.get(i);
                final String actualName = zipItem.baseName() + "." + zipItem.type();
                Assertions.assertThat(actualName).isEqualTo(expectedName);
                Assertions.assertThat(zipItem.content().length()).isGreaterThan(1);
            }
        });
    }
Assert that a http header is present and has this value
stroom-proxy/stroom-proxy-app/src/test/java/stroom/proxy/app/MockHttpDestination.java