@Override
    public Map<String, String> getAll() {
        return flags.values().stream().collect(Collectors.toMap(flag -> flag.name, flag -> flag.value));
    }
@Test
    void testFeatureFlagResourcesCouldBeRead() throws Exception {
        String file = Objects.requireNonNull(this.getClass()
                .getResource("/org/graylog2/featureflag/custom-feature-flag.config")).toURI().getPath();

        FeatureFlags flags = factory.createImmutableFeatureFlags(file, metricRegistry);

        assertThat(flags.getAll().keySet()).contains("feature1");
    }