JPA 实体必须进行单元测试，如何进行？

Question

我有一个 Spring MVC 应用程序（Spring Boot v. 1.2.5），它使用 JPA 与流行的 Sql 数据库进行交互。
因此，我有几个实体映射了数据库中的所有表。显然，这些类只有 getter/setter 和实体之间关系的注释。

例如：

@Entity
@Table
public class Article {

    @Id
    @GeneratedValue(strategy = GenerationType.IDENTITY)
    @JsonView(View.Private.class)
    private Long id;

    @Column(nullable = false)
    @JsonView(View.Public.class)
    private String name;

    @ManyToOne(optional = false, fetch = FetchType.LAZY)
    @JoinColumn(name = "categoryId", nullable = false, updatable = false)
    @JsonIgnore
    private Category category;

   //Constructors Getters and Setters
   ...
}

我的问题是：我应该对这些类进行单元测试吗？我应该测试什么？如何

Answer 1

我建议你测试你写的所有东西（或者你选择写）......所以在这种情况下，我看到以下元素：

@GeneratedValue(strategy = GenerationType.IDENTITY)
@Column(nullable = false)
@ManyToOne(optional = false, fetch = FetchType.LAZY)
@JoinColumn(name = "categoryId", nullable = false, updatable = false)

您使用此注释定义了一些行为（我只从 JPA 中选择了那些行为，同样的事情应该用 JSONView 注释完成），并且如果一切正常（如您定义的那样），您希望进行单元测试。

@Test(expect = SQLException.class)
public void should_not_allow_null_name() {
    /* Given */ Article article = new Article(null, new Category());
    /* When */  articleRepository.save(article);
}

通过这种（简单的）测试，您可以遵循行为是否尊重您已实现的内容。如果有人（可能是您自己）删除了此注释，您将收到警报。

但是不要测试默认行为（例如，列名，你选择让JPA（和ORM）为你选择......所以不要测试框架，这是限制。

关于如何测试它，我喜欢使用（自 Spring Boot 以来）名为 DBSetup 的项目。它允许我在我的测试中硬编码我的数据集，而不是冗长的 XML。这是忍者小队的一个非常有趣的项目。

测试示例：

数据库测试配置：

@Configuration
@EnableJpaRepositories(basePackages = "lan.dk.podcastserver.repository")
@EntityScan(basePackages = "lan.dk.podcastserver.entity")
public class DatabaseConfiguraitonTest {

    @Bean
    public DataSource dataSource() {
        return new EmbeddedDatabaseBuilder()
                .setType(EmbeddedDatabaseType.H2)
                .build();
    }

    @Bean
    @Autowired
    public FullTextEntityManager fullTextEntityManager(EntityManager entityManager) {
        return getFullTextEntityManager(entityManager);
    }

    public static final DateTimeFormatter formatter = new DateTimeFormatterBuilder().append(DateTimeFormatter.ISO_LOCAL_DATE).appendLiteral(" ").append(DateTimeFormatter.ISO_LOCAL_TIME).toFormatter();
    public static final Operation DELETE_ALL_PODCASTS = deleteAllFrom("PODCAST");
    public static final Operation DELETE_ALL_ITEMS = deleteAllFrom("ITEM");
    public static final Operation DELETE_ALL_TAGS = sequenceOf(deleteAllFrom("PODCAST_TAG"), deleteAllFrom("TAG"));
    public static final Operation DELETE_ALL = sequenceOf(DELETE_ALL_ITEMS, DELETE_ALL_TAGS, DELETE_ALL_PODCASTS, DELETE_ALL_TAGS);
}

==> https://gist.github.com/davinkevin/bb4f62aaec031b68b8f3

并测试：

@Transactional
@RunWith(SpringJUnit4ClassRunner.class)
@ContextConfiguration(classes = {DatabaseConfiguraitonTest.class, HibernateJpaAutoConfiguration.class})
public class ItemRepositoryTest {

    @Autowired DataSource dataSource;
    @Autowired ItemRepository itemRepository;

    private final static DbSetupTracker dbSetupTracker = new DbSetupTracker();
    public static final Operation INSERT_REFERENCE_DATA = sequenceOf(
            insertInto("PODCAST")
                    .columns("ID", "TITLE", "URL", "TYPE", "HAS_TO_BE_DELETED")
                    .values(1, "AppLoad", null, "RSS", false)
                    .values(2, "Geek Inc HD", "http://fake.url.com/rss", "YOUTUBE", true)
                    .build(),
            insertInto("ITEM")
                    .columns("ID", "TITLE", "URL", "PODCAST_ID", "STATUS", "PUBDATE", "DOWNLOADDDATE")
                    .values(1L, "Appload 1", "http://fakeurl.com/appload.1.mp3", 1, Status.FINISH, now().minusDays(15).format(formatter), now().minusDays(15).format(formatter))
                    .values(2L, "Appload 2", "http://fakeurl.com/appload.2.mp3", 1, null, now().minusDays(30).format(formatter), null)
                    .values(3L, "Appload 3", "http://fakeurl.com/appload.3.mp3", 1, Status.NOT_DOWNLOADED, now().format(formatter), null)
                    .values(4L, "Geek INC 123", "http://fakeurl.com/geekinc.123.mp3", 2, Status.DELETED, now().minusYears(1).format(formatter), now().format(formatter))
                    .values(5L, "Geek INC 124", "http://fakeurl.com/geekinc.124.mp3", 2, Status.FINISH, now().minusDays(15).format(formatter), now().minusDays(15).format(formatter))
                    .build(),
            insertInto("TAG")
                    .columns("ID", "NAME")
                    .values(1L, "French Spin")
                    .values(2L, "Studio Knowhere")
                    .build(),
            insertInto("PODCAST_TAG")
                    .columns("PODCAST_ID", "TAG_ID")
                    .values(1, 1)
                    .values(2, 2)
                    .build()
    );

    @Before
    public void prepare() throws Exception {
        Operation operation = sequenceOf(DELETE_ALL, INSERT_REFERENCE_DATA);
        DbSetup dbSetup = new DbSetup(new DataSourceDestination(dataSource), operation);

        dbSetupTracker.launchIfNecessary(dbSetup);
    }

    @Test
    public void should_find_by_podcast_and_page() {
        /* Given */
        dbSetupTracker.skipNextLaunch();
        Integer podcastId = 1;
        PageRequest pageRequest = new PageRequest(1, 1, Sort.Direction.ASC, "id");

        /* When */
        Page<Item> itemByPodcast = itemRepository.findByPodcast(podcastId, pageRequest);

        /* Then */
        PageAssert
                .assertThat(itemByPodcast)
                .hasSize(1)
                .hasTotalElements(3)
                .hasTotalPages(3)
                .hasNumberOfElements(1);

        ItemAssert
                .assertThat(itemByPodcast.getContent().get(0))
                .hasTitle("Appload 2");
    }

==> https://gist.github.com/davinkevin/df041729608dc21bf7f3