Spring Boot RESTful API 开发与测试指南

2. 实体类定义

使用 JPA 注解映射数据库表结构，这里以 Product 为例：

import javax.persistence.*;

@Entity
@Table(name = "product")
public class Product {
    @Id
    @GeneratedValue(strategy = GenerationType.IDENTITY)
    private Long id;
    
    private String productId;
    private String productName;
    private double price;
    private int sales;

    // Getter 和 Setter 方法省略...
    
    @Override
    public String toString() {
        return "Product{" +
                "id=" + id +
                ", productId='" + productId + '\'' +
                ", productName='" + productName + '\'' +
                ", price=" + price +
                ", sales=" + sales +
                '}';
    }
}

3. 数据访问层 (Repository)

继承 JpaRepository 即可快速获得基础 CRUD 能力，还可以自定义查询方法：

import org.springframework.data.jpa.repository.JpaRepository;
import org.springframework.stereotype.Repository;
import java.util.List;

@Repository
public interface ProductRepository extends JpaRepository<Product, Long> {
    List<Product> findBySalesGreaterThan(int sales);
}

4. 业务逻辑层 (Service)

Service 层负责事务管理和复杂逻辑编排：

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;
import org.springframework.transaction.annotation.Transactional;
import java.util.List;

@Service
public class ProductService {
    @Autowired
    private ProductRepository productRepository;

    @Transactional
    public void addProduct(Product product) {
        productRepository.save(product);
    }

    @Transactional
    public void updateProduct(Product product) {
        productRepository.save(product);
    }

    @Transactional
    public void deleteProduct(Long id) {
        productRepository.deleteById(id);
    }

    @Transactional(readOnly = true)
    public List<Product> getAllProducts() {
        return productRepository.findAll();
    }

    @Transactional(readOnly = true)
    public List<Product> getTopSellingProducts(int topN) {
        List<Product> products = productRepository.findBySalesGreaterThan(0);
        products.sort((p1, p2) -> p2.getSales() - p1.getSales());
        if (products.size() > topN) {
            return products.subList(0, topN);
        }
        return products;
    }
}

5. 控制器层 (Controller)

使用 @RestController 和 @RequestMapping 等注解暴露接口：

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.http.HttpStatus;
import org.springframework.http.ResponseEntity;
import org.springframework.web.bind.annotation.*;
import java.util.List;

@RestController
@RequestMapping("/api/products")
public class ProductController {
    @Autowired
    private ProductService productService;

    @GetMapping("/")
    public ResponseEntity<List<Product>> getAllProducts() {
        List<Product> products = productService.getAllProducts();
        return new ResponseEntity<>(products, HttpStatus.OK);
    }

    @PostMapping("/")
    public ResponseEntity<Void> addProduct(@RequestBody Product product) {
        productService.addProduct(product);
        return new ResponseEntity<>(HttpStatus.CREATED);
    }

    @PutMapping("/{id}")
    public ResponseEntity<Void> updateProduct(@PathVariable Long id, @RequestBody Product product) {
        product.setId(id);
        productService.updateProduct(product);
        return new ResponseEntity<>(HttpStatus.OK);
    }

    @DeleteMapping("/{id}")
    public ResponseEntity<Void> deleteProduct(@PathVariable Long id) {
        productService.deleteProduct(id);
        return new ResponseEntity<>(HttpStatus.NO_CONTENT);
    }

    @GetMapping("/top-selling")
    public ResponseEntity<List<Product>> getTopSellingProducts(@RequestParam int topN) {
        List<Product> products = productService.getTopSellingProducts(topN);
        return new ResponseEntity<>(products, HttpStatus.OK);
    }
}

测试策略

为了保证代码质量，我们需要覆盖不同层面的测试。

单元测试

主要针对 Service 层的逻辑进行验证，无需启动整个容器：

import org.junit.jupiter.api.Test;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.test.context.SpringBootTest;
import java.util.List;
import static org.assertj.core.api.Assertions.assertThat;

@SpringBootTest
class ProductServiceTests {
    @Autowired
    private ProductService productService;

    @Test
    void testAddProduct() {
        Product product = new Product("P006", "平板", 2000.0, 70);
        productService.addProduct(product);
        List<Product> products = productService.getAllProducts();
        assertThat(products).hasSize(6);
    }
}

集成测试

测试 Controller 与外部交互的情况，需要启动真实服务器端口：

import org.junit.jupiter.api.Test;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.test.context.SpringBootTest;
import org.springframework.boot.test.web.client.TestRestTemplate;
import org.springframework.boot.web.server.LocalServerPort;
import java.util.List;
import static org.assertj.core.api.Assertions.assertThat;

@SpringBootTest(webEnvironment = SpringBootTest.WebEnvironment.RANDOM_PORT)
class ProductControllerTests {
    @LocalServerPort
    private int port;
    
    @Autowired
    private TestRestTemplate restTemplate;

    @Test
    void testGetAllProducts() {
        List<Product> products = restTemplate.getForObject("http://localhost:" + port + "/api/products/", List.class);
        assertThat(products).hasSize(5);
    }
}

Mock 测试

针对 Controller 层，Mock 掉 Service 依赖，专注于接口响应验证：

import org.junit.jupiter.api.Test;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.test.autoconfigure.web.servlet.WebMvcTest;
import org.springframework.boot.test.mock.mockito.MockBean;
import org.springframework.http.MediaType;
import org.springframework.test.web.servlet.MockMvc;
import java.util.Arrays;
import java.util.List;
import static org.mockito.ArgumentMatchers.any;
import static org.mockito.Mockito.*;
import static org.springframework.test.web.servlet.request.MockMvcRequestBuilders.*;
import static org.springframework.test.web.servlet.result.MockMvcResultMatchers.*;

@WebMvcTest(ProductController.class)
class ProductControllerMockTests {
    @Autowired
    private MockMvc mockMvc;
    
    @MockBean
    private ProductService productService;

    @Test
    void testGetAllProducts() throws Exception {
        List<Product> products = Arrays.asList(
            new Product("P001", "手机", 1000.0, 100),
            new Product("P002", "电脑", 5000.0, 50)
        );
        when(productService.getAllProducts()).thenReturn(products);
        mockMvc.perform(get("/api/products/"))
               .andExpect(status().isOk())
               .andExpect(content().contentType(MediaType.APPLICATION_JSON));
        verify(productService, times(1)).getAllProducts();
    }
}

安全认证与授权

生产环境中的 API 必须考虑安全性，Spring Security 提供了完善的解决方案。

基础认证 (Basic Auth)

适用于内部系统或简单场景，通过用户名密码直接鉴权：

import org.springframework.context.annotation.Configuration;
import org.springframework.security.config.annotation.authentication.builders.AuthenticationManagerBuilder;
import org.springframework.security.config.annotation.web.builders.HttpSecurity;
import org.springframework.security.config.annotation.web.configuration.EnableWebSecurity;
import org.springframework.security.config.annotation.web.configuration.WebSecurityConfigurerAdapter;
import org.springframework.security.crypto.password.NoOpPasswordEncoder;

@Configuration
@EnableWebSecurity
public class SecurityConfig extends WebSecurityConfigurerAdapter {
    @Override
    protected void configure(AuthenticationManagerBuilder auth) throws Exception {
        auth.inMemoryAuthentication()
            .passwordEncoder(NoOpPasswordEncoder.getInstance())
            .withUser("admin").password("admin123").roles("ADMIN")
            .and()
            .withUser("user").password("user123").roles("USER");
    }

    @Override
    protected void configure(HttpSecurity http) throws Exception {
        http.authorizeRequests()
            .antMatchers("/api/products/top-selling").hasRole("ADMIN")
            .antMatchers("/api/products/**").hasRole("USER")
            .and().httpBasic();
    }
}

JWT 无状态认证

对于前后端分离架构，JWT 更为常用。客户端登录后获取 Token，后续请求携带 Token 即可：

工具类生成与校验：

import io.jsonwebtoken.Claims;
import io.jsonwebtoken.Jwts;
import io.jsonwebtoken.SignatureAlgorithm;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.stereotype.Component;
import java.util.Date;
import java.util.HashMap;
import java.util.Map;
import java.util.function.Function;

@Component
public class JwtUtil {
    @Value("${jwt.secret}")
    private String secret;
    
    @Value("${jwt.expiration}")
    private Long expiration;

    public String generateToken(String username) {
        Map<String, Object> claims = new HashMap<>();
        return createToken(claims, username);
    }

    private String createToken(Map<String, Object> claims, String subject) {
        return Jwts.builder()
                .setClaims(claims)
                .setSubject(subject)
                .setIssuedAt(new Date(System.currentTimeMillis()))
                .setExpiration(new Date(System.currentTimeMillis() + expiration * 1000))
                .signWith(SignatureAlgorithm.HS256, secret)
                .compact();
    }

    public Boolean validateToken(String token, String username) {
        final String extractedUsername = extractUsername(token);
        return (extractedUsername.equals(username) && !isTokenExpired(token));
    }

    private String extractUsername(String token) {
        return extractClaim(token, Claims::getSubject);
    }

    private Boolean isTokenExpired(String token) {
        return extractExpiration(token).before(new Date());
    }

    private <T> T extractClaim(String token, Function<Claims, T> claimsResolver) {
        final Claims claims = extractAllClaims(token);
        return claimsResolver.apply(claims);
    }

    private Claims extractAllClaims(String token) {
        return Jwts.parser().setSigningKey(secret).parseClaimsJws(token).getBody();
    }

    private Date extractExpiration(String token) {
        return extractClaim(token, Claims::getExpiration);
    }
}

过滤器拦截请求：

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.security.authentication.UsernamePasswordAuthenticationToken;
import org.springframework.security.core.context.SecurityContextHolder;
import org.springframework.security.core.userdetails.UserDetails;
import org.springframework.security.core.userdetails.UserDetailsService;
import org.springframework.security.web.authentication.WebAuthenticationDetailsSource;
import org.springframework.stereotype.Component;
import org.springframework.web.filter.OncePerRequestFilter;
import javax.servlet.FilterChain;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;

@Component
public class JwtRequestFilter extends OncePerRequestFilter {
    @Autowired
    private UserDetailsService userDetailsService;
    
    @Autowired
    private JwtUtil jwtUtil;

    @Override
    protected void doFilterInternal(HttpServletRequest request, HttpServletResponse response, FilterChain chain)
            throws ServletException, IOException {
        final String authorizationHeader = request.getHeader("Authorization");
        String username = null;
        String jwt = null;

        if (authorizationHeader != null && authorizationHeader.startsWith("Bearer ")) {
            jwt = authorizationHeader.substring(7);
            username = jwtUtil.extractUsername(jwt);
        }

        if (username != null && SecurityContextHolder.getContext().getAuthentication() == null) {
            UserDetails userDetails = this.userDetailsService.loadUserByUsername(username);
            if (jwtUtil.validateToken(jwt, userDetails.getUsername())) {
                UsernamePasswordAuthenticationToken usernamePasswordAuthenticationToken =
                        new UsernamePasswordAuthenticationToken(userDetails, null, userDetails.getAuthorities());
                usernamePasswordAuthenticationToken.setDetails(new WebAuthenticationDetailsSource().buildDetails(request));
                SecurityContextHolder.getContext().setAuthentication(usernamePasswordAuthenticationToken);
            }
        }
        chain.doFilter(request, response);
    }
}

配置文件示例：

server.port=8080
spring.datasource.url=jdbc:h2:mem:testdb
spring.datasource.driver-class-name=org.h2.Driver
spring.datasource.username=sa
spring.datasource.password=password
spring.jpa.hibernate.ddl-auto=update
spring.jpa.show-sql=true
spring.h2.console.enabled=true
spring.h2.console.path=/h2-console
jwt.secret=mysecret
jwt.expiration=3600

场景落地

实际项目中，RESTful API 广泛应用于商品展示、订单管理、用户中心及博客发布等场景。通过上述分层设计与安全机制，可以快速构建出稳定、可扩展的后端服务。

例如，访问 http://localhost:8080/api/products/ 可获取产品列表，而 http://localhost:8080/api/products/top-selling?topN=3 则返回销量前三的商品。结合测试用例的持续运行，能有效保障功能迭代过程中的稳定性。