如何在单元测试中设置不同的类路径以使用 Spring 加载资源

Question

我想用 JUnit 和 Spring 创建 2 个测试用例，它们都需要相同的 classpath 资源 batch-configuration.properties但此文件的内容因测试而异。

实际上在我的 maven 项目中，我创建了这些文件树：

src/test/resources/test1/batch-configuration.properties
src/test/resources/test2/batch-configuration.properties

但是我如何根据我的测试用例定义我的根 class 路径（文件使用 classpath:batch-configuration.properties 在 ExtractionBatchConfiguration 中加载）

@RunWith(SpringJUnit4ClassRunner.class)
@ContextConfiguration(classes = { ExtractionBatchConfiguration.class }, loader = AnnotationConfigContextLoader.class)
@PropertySource("classpath:test1/batch-configuration.properties") // does not override ExtractionBatchConfiguration declaration
public class ExtractBatchTestCase {
    private static ConfigurableApplicationContext context;

    private JobLauncherTestUtils jobLauncherTestUtils;

    @BeforeClass
    public static void beforeClass() {
        context = SpringApplication.run(ExtractionBatchConfiguration.class);
    }

    @Before
    public void setup() throws Exception {      
        jobLauncherTestUtils = new JobLauncherTestUtils();
        jobLauncherTestUtils.setJobLauncher(context.getBean(JobLauncher.class));
        jobLauncherTestUtils.setJobRepository(context.getBean(JobRepository.class));
    }

    @Test
    public void testGeneratedFiles() throws Exception {     
        jobLauncherTestUtils.setJob(context.getBean("extractJob1", Job.class));
        JobExecution jobExecution = jobLauncherTestUtils.launchJob();
        Assert.assertNotNull(jobExecution);
        Assert.assertEquals(BatchStatus.COMPLETED, jobExecution.getStatus());
        Assert.assertEquals(ExitStatus.COMPLETED, jobExecution.getExitStatus());
        // ... other assert
    }

}

配置：

@Configuration
@EnableAutoConfiguration
@PropertySources({
    @PropertySource("batch-default-configuration.properties"),
    @PropertySource("batch-configuration.properties")
})
public class ExtractionBatchConfiguration { /* ... */ }

我正在使用 Spring 4.0.9（我不能使用 4.1.x）和 JUnit 4.11

编辑：

在使用 hzpz 建议的自定义 ApplicationContextInitializer 覆盖我的解决了一些问题的属性位置（application.properties + batch-configuration.properties）之后，我遇到了 @ConfigurationProperties 的另一个问题：

@ConfigurationProperties(prefix = "spring.ldap.contextsource"/*, locations = "application.properties"*/) 
public class LdapSourceProperties { 
    String url;
    String userDn;
    String password;
    /* getters, setters */
}

和配置：

@Configuration
@EnableConfigurationProperties(LdapSourceProperties.class)
public class LdapConfiguration {
    @Bean
    public ContextSource contextSource(LdapSourceProperties properties) {
        LdapContextSource contextSource = new LdapContextSource();
        contextSource.setUrl(properties.getUrl());
        contextSource.setUserDn(properties.getUserDn());
        contextSource.setPassword(properties.getPassword());
        return contextSource;
    }
}

创建 ContextSource 时，所有 LdapSourceProperties 的字段均为空，但如果我取消注释 locations = "application.properties"，它仅在 application.properties 位于根 class 路径中时才有效。 @ConfigurationProperties 使用的默认环境似乎不包含需要的属性...

备选方案：

最后，我将所有属性放入 application-<profile>.properties 文件（并删除 @PropertySource 定义）。我现在可以使用 application-test1.properties 和 application-test2.properties。在我的测试 class 中，我可以设置 @ActiveProfiles("test1") 来激活配置文件并加载相关属性。

Answer 1

首先，您需要了解 Spring 的 JUnit 测试是如何工作的。 SpringJUnit4ClassRunner 的目的是为您创建 ApplicationContext（使用 @ContextConfiguration）。您不需要自己创建上下文。

如果上下文设置正确，您可以使用 @Autowired 获取测试中所需的依赖项。 ExtractBatchTestCase 应该看起来像这样：

@RunWith(SpringJUnit4ClassRunner.class)
@ContextConfiguration(classes = { ExtractionBatchConfiguration.class })
public class ExtractBatchTestCase {

    @Autowired
    private JobLauncher jobLauncher;

    @Autowired
    private JobRepository jobRepository;

    @Autowired
    @Qualifier("extractJob1")
    private Job job;

    private JobLauncherTestUtils jobLauncherTestUtils;

    @Before
    public void setup() throws Exception {      
        jobLauncherTestUtils = new JobLauncherTestUtils();
        jobLauncherTestUtils.setJobLauncher(jobLauncher);
        jobLauncherTestUtils.setJobRepository(jobRepository);
    }

    @Test
    public void testGeneratedFiles() throws Exception {     
        jobLauncherTestUtils.setJob(job);
        JobExecution jobExecution = jobLauncherTestUtils.launchJob();
        Assert.assertNotNull(jobExecution);
        Assert.assertEquals(BatchStatus.COMPLETED, jobExecution.getStatus());
        Assert.assertEquals(ExitStatus.COMPLETED, jobExecution.getExitStatus());
        // ... other assert
    }

}

其次，@ProperySource 的 Javadoc 声明：

In cases where a given property key exists in more than one .properties file, the last @PropertySource annotation processed will 'win' and override. [...]

In certain situations, it may not be possible or practical to tightly control property source ordering when using @ProperySource annotations. For example, if the @Configuration classes [...] were registered via component-scanning, the ordering is difficult to predict. In such cases - and if overriding is important - it is recommended that the user fall back to using the programmatic PropertySource API.

为您的测试创建一个 ApplicationContextInitializer 以添加一些具有最高搜索优先级的测试属性，这些属性将始终 'win':

public class MockApplicationContextInitializer implements ApplicationContextInitializer<ConfigurableApplicationContext> {

    @Override
    public void initialize(ConfigurableApplicationContext applicationContext) {
        MutablePropertySources propertySources = applicationContext.getEnvironment().getPropertySources();
        MockPropertySource mockEnvVars = new MockPropertySource().withProperty("foo", "bar");
        propertySources.addFirst(mockEnvVars);
    }
}

使用@ContextConfiguration声明它：

@RunWith(SpringJUnit4ClassRunner.class)
@ContextConfiguration(classes = { ExtractionBatchConfiguration.class }, 
                      initializers = MockApplicationContextInitializer.class)
public class ExtractBatchTestCase {
    // ...
}

如何在单元测试中设置不同的类路径以使用 Spring 加载资源

How to set different classpath in an unit test to load resource with Spring

java

spring

unit-testing

spring-batch

spring-boot