ImageArchiveTests Class — spring-boot Architecture

Source Code

buildpack/spring-boot-buildpack-platform/src/test/java/org/springframework/boot/buildpack/platform/docker/type/ImageArchiveTests.java lines 41–101

class ImageArchiveTests extends AbstractJsonTests {

	private static final int EXISTING_IMAGE_LAYER_COUNT = 46;

	@Test
	void fromImageWritesToValidArchiveTar() throws Exception {
		Image image = Image.of(getContent("image.json"));
		ImageArchive archive = ImageArchive.from(image, (update) -> {
			update.withNewLayer(Layer.of((layout) -> layout.directory("/spring", Owner.ROOT)));
			update.withTag(ImageReference.of("pack.local/builder/6b7874626575656b6162"));
		});
		ByteArrayOutputStream outputStream = new ByteArrayOutputStream();
		archive.writeTo(outputStream);
		try (TarArchiveInputStream tar = new TarArchiveInputStream(
				new ByteArrayInputStream(outputStream.toByteArray()))) {
			for (int i = 0; i < EXISTING_IMAGE_LAYER_COUNT; i++) {
				TarArchiveEntry blankEntry = tar.getNextEntry();
				assertThat(blankEntry.getName()).isEqualTo("blank_" + i);
			}
			TarArchiveEntry layerEntry = tar.getNextEntry();
			byte[] layerContent = read(tar, layerEntry.getSize());
			TarArchiveEntry configEntry = tar.getNextEntry();
			byte[] configContent = read(tar, configEntry.getSize());
			TarArchiveEntry manifestEntry = tar.getNextEntry();
			byte[] manifestContent = read(tar, manifestEntry.getSize());
			assertExpectedLayer(layerEntry, layerContent);
			assertExpectedConfig(configEntry, configContent);
			assertExpectedManifest(manifestEntry, manifestContent);
		}
	}

	private void assertExpectedLayer(TarArchiveEntry entry, byte[] content) throws Exception {
		assertThat(entry.getName()).isEqualTo("bb09e17fd1bd2ee47155f1349645fcd9fff31e1247c7ed99cad469f1c16a4216.tar");
		try (TarArchiveInputStream tar = new TarArchiveInputStream(new ByteArrayInputStream(content))) {
			TarArchiveEntry contentEntry = tar.getNextEntry();
			assertThat(contentEntry.getName()).isEqualTo("/spring/");
		}
	}

	private void assertExpectedConfig(TarArchiveEntry entry, byte[] content) throws Exception {
		assertThat(entry.getName()).isEqualTo("416c76dc7f691f91e80516ff039e056f32f996b59af4b1cb8114e6ae8171a374.json");
		String actualJson = new String(content, StandardCharsets.UTF_8);
		String expectedJson = StreamUtils.copyToString(getContent("image-archive-config.json"), StandardCharsets.UTF_8);
		JSONAssert.assertEquals(expectedJson, actualJson, false);
	}

	private void assertExpectedManifest(TarArchiveEntry entry, byte[] content) throws Exception {
		assertThat(entry.getName()).isEqualTo("manifest.json");
		String actualJson = new String(content, StandardCharsets.UTF_8);
		String expectedJson = StreamUtils.copyToString(getContent("image-archive-manifest.json"),
				StandardCharsets.UTF_8);
		JSONAssert.assertEquals(expectedJson, actualJson, false);
	}

	private byte[] read(TarArchiveInputStream tar, long size) throws IOException {
		byte[] content = new byte[(int) size];
		tar.read(content);
		return content;
	}

}