SpringBoot3之Web编程

标签：Rest.拦截器.swagger.测试;

一、简介

基于web包的依赖，SpringBoot可以快速启动一个web容器，简化项目的开发；

在web开发中又涉及如下几个功能点：

拦截器：可以让接口被访问之前，将请求拦截到，通过对请求的识别和校验，判断请求是否允许通过；

页面交互：对于服务端的开发来说，需要具备简单的页面开发能力，解决部分场景的需求；

Swagger接口：通过简单的配置，快速生成接口的描述，并且提供对接口的测试能力；

Junit测试：通过编写代码的方式对接口进行测试，从而完成对接口的检查和验证，并且可以不入侵原代码结构；

二、工程搭建

1、工程结构

2、依赖管理

<!-- 基础框架组件 -->
<dependency>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-starter-web</artifactId>
    <version>${spring-boot.version}</version>
</dependency>
<!-- 接口文档组件 -->
<dependency>
    <groupId>org.springdoc</groupId>
    <artifactId>springdoc-openapi-starter-webmvc-ui</artifactId>
    <version>${springdoc.version}</version>
</dependency>
<!-- 前端页面组件 -->
<dependency>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-starter-thymeleaf</artifactId>
    <version>${spring-boot.version}</version>
</dependency>
<!-- 单元测试组件 -->
<dependency>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-starter-test</artifactId>
    <version>${spring-boot.version}</version>
    <exclusions>
        <exclusion>
            <groupId>org.slf4j</groupId>
            <artifactId>slf4j-api</artifactId>
        </exclusion>
    </exclusions>
</dependency>
<dependency>
    <groupId>junit</groupId>
    <artifactId>junit</artifactId>
    <version>${junit.version}</version>
</dependency>

三、Web开发

1、接口开发

编写四个简单常规的接口，从对资源操作的角度，也就是常说的：增Post、删Delete、改Put、查Get，并且使用了swagger注解，可以快速生成接口文档；

@RestController
@Tag(name = "Rest接口")
public class RestWeb {

    @Operation(summary = "Get接口")
    @GetMapping("rest/get/{id}")
    public String restGet(@PathVariable Integer id) {
        return "OK:"+id;
    }

    @Operation(summary = "Post接口")
    @PostMapping("/rest/post")
    public String restPost(@RequestBody ParamBO param){
        return "OK:"+param.getName();
    }

    @Operation(summary = "Put接口")
    @PutMapping("/rest/put")
    public String restPut(@RequestBody ParamBO param){
        return "OK:"+param.getId();
    }

    @Operation(summary = "Delete接口")
    @DeleteMapping("/rest/delete/{id}")
    public String restDelete(@PathVariable Integer id){
        return "OK:"+id;
    }
}

2、页面交互

对于服务端开发来说，在部分场景下是需要进行简单的页面开发的，比如通过页面渲染再去生成文件，或者直接通过页面填充邮件内容等；

数据接口

@Controller
public class PageWeb {

    @RequestMapping("/page/view")
    public ModelAndView pageView (HttpServletRequest request){
        ModelAndView modelAndView = new ModelAndView() ;
        // 普通参数
        modelAndView.addObject("name", "cicada");
        modelAndView.addObject("time", "2023-07-12");
        // 对象模型
        modelAndView.addObject("page", new PageBO(7,"页面数据模型"));
        // List集合
        List<PageBO> pageList = new ArrayList<>() ;
        pageList.add(new PageBO(1,"第一页"));
        pageList.add(new PageBO(2,"第二页"));
        modelAndView.addObject("pageList", pageList);
        // Array数组
        PageBO[] pageArr = new PageBO[]{new PageBO(6,"第六页"),new PageBO(7,"第七页")} ;
        modelAndView.addObject("pageArr", pageArr);
        modelAndView.setViewName("/page-view");
        return modelAndView ;
    }
}

页面解析：分别解析了普通参数，实体对象，集合容器，数组容器等几种数据模型；

<div style="text-align: center">
    <hr/>
    <h5>普通参数解析</h5>
    姓名：<span th:text="${name}"></span>
    时间：<span th:text="${time}"></span>
    <hr/>
    <h5>对象模型解析</h5>
    整形：<span th:text="${page.getKey()}"></span>
    字符：<span th:text="${page.getValue()}"></span>
    <hr/>
    <h5>集合容器解析</h5>
    <table style="margin:0 auto;width: 200px">
        <tr>
            <th>Key</th>
            <th>Value</th>
        </tr>
        <tr th:each="page:${pageList}">
            <td th:text="${page.getKey()}"></td>
            <td th:text="${page.getValue()}"></td>
        </tr>
    </table>
    <hr/>
    <h5>数组容器解析</h5>
    <table style="margin:0 auto;width: 200px">
        <tr>
            <th>Key</th>
            <th>Value</th>
        </tr>
        <tr th:each="page:${pageArr}">
            <td th:text="${page.getKey()}"></td>
            <td th:text="${page.getValue()}"></td>
        </tr>
    </table>
    <hr/>
</div>

效果图展示

四、拦截器

1、拦截器定义

通过实现HandlerInterceptor接口，完成对两个拦截器的自定义，请求在访问服务时，必须通过两个拦截器的校验；

/**
 * 拦截器一
 */
public class HeadInterceptor implements HandlerInterceptor {
    private static final Logger log  = LoggerFactory.getLogger(HeadInterceptor.class);
    @Override
    public boolean preHandle(HttpServletRequest request, HttpServletResponse response,
                             Object handler) throws Exception {
        log.info("HeadInterceptor:preHandle");
        Iterator<String> headNames = request.getHeaderNames().asIterator();
        log.info("request-header");
        while (headNames.hasNext()){
            String headName = headNames.next();
            String headValue = request.getHeader(headName);
            System.out.println(headName+":"+headValue);
        }
        // 放开拦截
        return true;
    }
    @Override
    public void postHandle(HttpServletRequest request,HttpServletResponse response,
                           Object handler, ModelAndView modelAndView) throws Exception {
        log.info("HeadInterceptor:postHandle");
    }
    @Override
    public void afterCompletion(HttpServletRequest request,HttpServletResponse response,
                                Object handler, Exception e) throws Exception {
        log.info("HeadInterceptor:afterCompletion");
    }
}

/**
 * 拦截器二
 */
public class BodyInterceptor implements HandlerInterceptor {
    private static final Logger log  = LoggerFactory.getLogger(BodyInterceptor.class);
    @Override
    public boolean preHandle(HttpServletRequest request,HttpServletResponse response,
                             Object handler) throws Exception {
        log.info("BodyInterceptor:preHandle");
        Iterator<String> paramNames = request.getParameterNames().asIterator();
        log.info("request-param");
        while (paramNames.hasNext()){
            String paramName = paramNames.next();
            String paramValue = request.getParameter(paramName);
            System.out.println(paramName+":"+paramValue);
        }
        // 放开拦截
        return true;
    }
    @Override
    public void postHandle(HttpServletRequest request,HttpServletResponse response,
                           Object handler, ModelAndView modelAndView) throws Exception {
        log.info("BodyInterceptor:postHandle");
    }
    @Override
    public void afterCompletion(HttpServletRequest request,HttpServletResponse response,
                                Object handler, Exception e) throws Exception {
        log.info("BodyInterceptor:afterCompletion");
    }
}

2、拦截器配置

自定义拦截器之后，还需要添加到web工程的配置文件中，可以通过实现WebMvcConfigurer接口，完成自定义的配置添加；

@Configuration
public class WebMvcConfig implements WebMvcConfigurer {

    /**
     * 添加自定义拦截器
     */
    @Override
    public void addInterceptors(InterceptorRegistry registry) {
        registry.addInterceptor(new HeadInterceptor()).addPathPatterns("/**");
        registry.addInterceptor(new BodyInterceptor()).addPathPatterns("/**");
    }
}

五、测试工具

1、Swagger接口

添加上述的springdoc依赖之后，还可以在配置文件中简单定义一些信息，访问IP:端口/swagger-ui/index.html即可；

@Configuration
public class WebMvcConfig implements WebMvcConfigurer {

    /**
     * 接口文档配置
     */
    @Bean
    public OpenAPI openAPI() {
        return new OpenAPI()
                .info(new Info().title("【boot-web】").description("Rest接口文档-2023-07-11")
                .version("1.0.0"));
    }
}

2、Junit测试

在个人的习惯上，Swagger接口文档更偏向在前后端对接的时候使用，而Junit单元测试更符合开发的时候使用，这里是对RestWeb中的接口进行测试；

@RunWith(SpringRunner.class)
@SpringBootTest
@AutoConfigureMockMvc
public class RestWebTest {

    @Autowired
    private MockMvc mockMvc;

    @Test
    public void testGet () throws Exception {
        // GET接口测试
        MvcResult mvcResult = mockMvc
                .perform(MockMvcRequestBuilders.get("/rest/get/1"))
                .andReturn();
        printMvcResult(mvcResult);
    }

    @Test
    public void testPost () throws Exception {
        // 参数模型
        JsonMapper jsonMapper = new JsonMapper();
        ParamBO param = new ParamBO(null,"单元测试",new Date()) ;
        String paramJson = jsonMapper.writeValueAsString(param) ;
        // Post接口测试
        MvcResult mvcResult = mockMvc.perform(MockMvcRequestBuilders.post("/rest/post")
                .contentType(MediaType.APPLICATION_JSON)
                .accept(MediaType.APPLICATION_JSON).content(paramJson)).andReturn();
        printMvcResult(mvcResult);
    }

    @Test
    public void testPut () throws Exception {
        // 参数模型
        JsonMapper jsonMapper = new JsonMapper();
        ParamBO param = new ParamBO(7,"Junit组件",new Date()) ;
        String paramJson = jsonMapper.writeValueAsString(param) ;
        // Put接口测试
        MvcResult mvcResult = mockMvc.perform(MockMvcRequestBuilders.put("/rest/put")
                .contentType(MediaType.APPLICATION_JSON)
                .accept(MediaType.APPLICATION_JSON).content(paramJson)).andReturn();
        printMvcResult(mvcResult);
    }

    @Test
    public void testDelete () throws Exception {
        // Delete接口测试
        MvcResult mvcResult = mockMvc
                .perform(MockMvcRequestBuilders.delete("/rest/delete/2"))
                .andReturn();
        printMvcResult(mvcResult);
    }

    /**
     * 打印【MvcResult】信息
     */
    private void printMvcResult (MvcResult mvcResult) throws Exception {
        System.out.println("请求-URI【"+mvcResult.getRequest().getRequestURI()+"】");
        System.out.println("响应-status【"+mvcResult.getResponse().getStatus()+"】");
        System.out.println("响应-content【"+mvcResult.getResponse().getContentAsString(StandardCharsets.UTF_8)+"】");
    }
}

六、参考源码

文档仓库：
https://gitee.com/cicadasmile/butte-java-note

源码仓库：
https://gitee.com/cicadasmile/butte-spring-parent