如何将@WebMvcTest 用于使用自动装配的 ConversionService 的控制器？

Question

在 Spring 引导应用程序中，我有两个 POJO，Foo 和 Bar，以及一个 BarToFooConverter，它看起来像：

@Component
public class BarToFooConverter implements Converter<Bar, Foo> {
    @Override
    public Foo convert(Bar bar) {
        return new Foo(bar.getBar());
    }
}

我还有一个使用转换器的控制器：

@RestController("test")
public class TestController {
    @Autowired
    private ConversionService conversionService;

    @RequestMapping(method = RequestMethod.PUT)
    @ResponseBody
    public Foo put(@RequestBody Bar bar) {
        return conversionService.convert(bar, Foo.class);
    }
}

我想用 @WebMvcTest 测试这个控制器，比如：

@WebMvcTest
@RunWith(SpringRunner.class)
public class TestControllerTest {
    @Autowired
    private MockMvc mockMvc;

    @Test
    public void test() throws Exception {
        mockMvc.perform(
                put("/test")
                        .contentType(MediaType.APPLICATION_JSON)
                        .content("{\"bar\":\"test\"}"))
                .andExpect(status().isOk());
    }
}

但是当我运行这个的时候，我发现我的 BarToFooConverter 没有注册到 ConversionService:

Caused by: org.springframework.core.convert.ConverterNotFoundException: No converter found capable of converting from type [com.example.demo.web.Bar] to type [com.example.demo.web.Foo]
    at org.springframework.core.convert.support.GenericConversionService.handleConverterNotFound(GenericConversionService.java:324)
    at org.springframework.core.convert.support.GenericConversionService.convert(GenericConversionService.java:206)
    at org.springframework.core.convert.support.GenericConversionService.convert(GenericConversionService.java:187)
    at com.example.demo.web.TestController.put(TestController.java:15)

这似乎是有道理的，因为，根据 the Javadoc:

Using this annotation will disable full auto-configuration and instead apply only configuration relevant to MVC tests (i.e. @Controller, @ControllerAdvice, @JsonComponent Filter, WebMvcConfigurer and HandlerMethodArgumentResolver beans but not @Component, @Service or @Repository beans).

然而，reference guide 略有不同，说 @WebMvcTest 包括 Converters:

@WebMvcTest auto-configures the Spring MVC infrastructure and limits scanned beans to @Controller, @ControllerAdvice, @JsonComponent, Converter, GenericConverter, Filter, WebMvcConfigurer, and HandlerMethodArgumentResolver. Regular @Component beans are not scanned when using this annotation.

这里的参考指南似乎不正确 - 还是我的 Converter 注册不正确？

我还尝试在测试中模拟 ConversionService：

@WebMvcTest
@RunWith(SpringRunner.class)
public class TestControllerTest {
    @Autowired
    private MockMvc mockMvc;

    @MockBean
    private ConversionService conversionService;

    @Test
    public void test() throws Exception {
        when(conversionService.convert(any(Bar.class), eq(Foo.class))).thenReturn(new Foo("test"));

        mockMvc.perform(
                put("/test")
                        .contentType(MediaType.APPLICATION_JSON)
                        .content("{\"bar\":\"test\"}"))
                .andExpect(status().isOk());
    }
}

但现在 Spring 抱怨我的模拟 ConversionService 覆盖了默认模拟：

Caused by: java.lang.IllegalStateException: @Bean method WebMvcConfigurationSupport.mvcConversionService called as a bean reference for type [org.springframework.format.support.FormattingConversionService] but overridden by non-compatible bean instance of type [org.springframework.core.convert.ConversionService$$EnhancerByMockitoWithCGLIB$$da4e303a]. Overriding bean of same name declared in: null
    at org.springframework.context.annotation.ConfigurationClassEnhancer$BeanMethodInterceptor.obtainBeanInstanceFromFactory(ConfigurationClassEnhancer.java:402)
    at org.springframework.context.annotation.ConfigurationClassEnhancer$BeanMethodInterceptor.intercept(ConfigurationClassEnhancer.java:361)
    ...

理想情况下，我想使用我原来的方法，在我的测试中使用真正的转换器而不是模拟 ConversionService，但使用 @WebMvcTest 来限制启动组件的范围，所以我也尝试在 @WebMvcTest 注释中使用 includeFilter：

@WebMvcTest(includeFilters = @ComponentScan.Filter(type = FilterType.REGEX, pattern = "com.example.demo.web.Bar*"))

但它仍然失败并显示原始 'No converter found capable of converting...' 错误消息。

这感觉像是一个很常见的要求 - 我错过了什么？

Answer 1

您可以在 @Before 注释方法中手动注册您的转换器。您所要做的就是注入 GenericConversionService and call addConverter(new BarToFooConverter()) 以使转换器可解析。在这种情况下，您可以摆脱模拟部分。您的测试可能如下所示：

import org.junit.Before;
import org.junit.Test;
import org.junit.runner.RunWith;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.test.autoconfigure.web.servlet.WebMvcTest;
import org.springframework.core.convert.support.GenericConversionService;
import org.springframework.http.MediaType;
import org.springframework.test.context.junit4.SpringRunner;
import org.springframework.test.web.servlet.MockMvc;

import static org.springframework.test.web.servlet.request.MockMvcRequestBuilders.put;
import static org.springframework.test.web.servlet.result.MockMvcResultMatchers.status;

@WebMvcTest
@RunWith(SpringRunner.class)
public class TestControllerTest {

    @Autowired
    private MockMvc mockMvc;

    @Autowired
    private GenericConversionService conversionService;

    @Before
    public void setup() {
        conversionService.addConverter(new BarToFooConverter());
    }

    @Test
    public void test() throws Exception {
        mockMvc.perform(
                put("/test")
                        .contentType(MediaType.APPLICATION_JSON)
                        .content("{\"bar\":\"test\"}"))
                .andExpect(status().isOk());
    }
}

替代解决方案：Spring 自版本 1.4.0 提供 collection of test-related auto-configurations and one of these auto-configurations is @AutoConfigureMockMvc 配置 MockMvc 组件，该组件可与注入转换器一起正常工作组件。

如何将@WebMvcTest 用于使用自动装配的 ConversionService 的控制器？

How can I use @WebMvcTest for a Controller that uses an autowired ConversionService?

java

spring-mvc

spring-mvc-test

spring-boot