Spring WebFlux 控制器中非响应式验证逻辑的集成与测试策略

@RestController
@RequestMapping("/api")
public class MangoController {

    private final MangoService serviceLayer;

    public MangoController(MangoService serviceLayer) {
        this.serviceLayer = serviceLayer;
    }

    @GetMapping("/mango/{id}")
    public Mono<Mango> getMango(@PathVariable("id") final String id) {
        // 非响应式验证方法
        validateId(id); 
        return serviceLayer.someMonoData();
    }

    private void validateId(String id) {
        if (id == null || id.isEmpty() || "invalid".equals(id)) {
            throw new IllegalArgumentException("Invalid ID provided"); // 假设抛出自定义异常
        }
        // 其他验证逻辑
    }
}

@GetMapping("/mango/{id}")
public Mono<Mango> getMango(@PathVariable("id") final String id) {
    // 将非响应式验证方法包装进响应式流
    return Mono.fromRunnable(() -> validateId(id))
               .then(serviceLayer.someMonoData()); // 使用 .then() 链式连接后续响应式操作
}

import org.junit.jupiter.api.Test;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.test.autoconfigure.web.reactive.WebFluxTest;
import org.springframework.boot.test.mock.mockito.MockBean;
import org.springframework.http.MediaType;
import org.springframework.test.web.reactive.server.WebTestClient;
import reactor.core.publisher.Mono;

import static org.mockito.Mockito.when;

@WebFluxTest(MangoController.class) // 只加载MangoController及其依赖
public class MangoControllerTest {

    @Autowired
    private WebTestClient webTestClient;

    @MockBean
    private MangoService serviceLayer; // 模拟服务层

    private static final String ENDPOINT_URL = "/api/mango/{id}";

    @Test
    public void getMango_withInvalidId_shouldReturnBadRequest() {
        // 当validateId抛出异常时，serviceLayer.someMonoData()不应被调用
        // 这里的stubbing是为了满足MockBean的要求，实际不会被触发
        when(serviceLayer.someMonoData()).thenReturn(Mono.just(new Mango("someId", "someName")));

        webTestClient.get()
                .uri(ENDPOINT_URL, "invalid") // 传入一个预期会触发验证异常的ID
                .accept(MediaType.APPLICATION_JSON)
                .exchange()
                .expectStatus()
                .isBadRequest() // 预期HTTP 400 Bad Request
                .expectBody()
                .jsonPath("$.message").isEqualTo("Invalid ID provided"); // 验证响应体中的错误信息，这取决于你的全局异常处理器
    }

    @Test
    public void getMango_withValidId_shouldReturnOk() {
        Mango expectedMango = new Mango("validId", "Sweet Mango");
        when(serviceLayer.someMonoData()).thenReturn(Mono.just(expectedMango));

        webTestClient.get()
                .uri(ENDPOINT_URL, "validId")
                .accept(MediaType.APPLICATION_JSON)
                .exchange()
                .expectStatus()
                .isOk()
                .expectBody(Mango.class)
                .isEqualTo(expectedMango);
    }

    // 假设Mango是一个简单的POJO
    static class Mango {
        public String id;
        public String name;

        public Mango(String id, String name) {
            this.id = id;
            this.name = name;
        }

        // 需要getter/setter和equals/hashCode方法以便WebTestClient正确比较
        public String getId() { return id; }
        public void setId(String id) { this.id = id; }
        public String getName() { return name; }
        public void setName(String name) { this.name = name; }

        @Override
        public boolean equals(Object o) {
            if (this == o) return true;
            if (o == null || getClass() != o.getClass()) return false;
            Mango mango = (Mango) o;
            return id.equals(mango.id) && name.equals(mango.name);
        }

        @Override
        public int hashCode() {
            return java.util.Objects.hash(id, name);
        }
    }
}