Spring Cloud微服务-4-SpringBoot日志，JSP，WebSocket等

SpringBoot日志处理

默认情况下，SpringBoot会引入spring-boot-starter-logging，也就是logback的日志实现。

在resources下新建logback-spring.xml可以自定义日志配置，这是约定的文件名字。

在spring-boot-starter-logging-2.1.4.RELEASE这个依赖中，在/org/springframework/boot/logging/logback/base.xml位置可以找到SpringBoot提供的一个默认配置，基于这个配置进行自定义

<?xml version="1.0" encoding="utf-8" ?>
<Configuration>
    <include resource="org/springframework/boot/logging/logback/base.xml" />
    <logger name="com.test.springlecture" level="DEBUG"/>
    <springProfile name="default">
        <logger name="com.test.springlecture" level="INFO"/>
    </springProfile>
</Configuration>

可以指定不同的springProfile，可以做到当在开发环境的时候打印debug日志，在生产的时候则打印info。

也可以直接在application.yml里配置日志级别：

logging:
  level:
    root: debug

SprintBoot整合JSP

现在用JSP的项目应该已经很少了，大部分都是前后端分离的项目。不过SpringBoot还是提供了对JSP的支持。

在SpringBoot中访问jsp，需要新增一个依赖，没有这个依赖，SpringBoot是无法编译jsp文件的。

'org.apache.tomcat.embed:tomcat-embed-jasper'

以及路径配置：

spring:
  mvc:
    view:
      prefix: /WEB-INF/jsp
      suffix: .jsp

SpringBoot整合WebSocket

SpringBoot对WebSocket也提供了强有力的支持，这里简单介绍一下如何在SpringBoot里开发WebSocket接口，首先引入依赖

'org.springframework.boot:spring-boot-starter-websocket',
'org.springframework.boot:spring-boot-starter-json'

/**
 * @author yangfan
 * @date 2019/11/23
 */
public interface EchoService {
    String getMessage(String message);
}

/**
 * @author yangfan
 * @date 2019/11/23
 */
public class DefaultEchoService implements EchoService {
    private final String echoFormat;

    public DefaultEchoService(String echoFormat) {
        this.echoFormat = echoFormat != null ? echoFormat : "%s";
    }

    @Override
    public String getMessage(String message) {
        return String.format(this.echoFormat, message);
    }
}

上面是用户的业务代码，下面是要实现TextWebSocketHandler，对WebSocket连接进行处理。

/**
 * @author yangfan
 * @date 2019/11/23
 */
public class EchoWebSocketHandler extends TextWebSocketHandler {

    private EchoService echoService;

    public EchoWebSocketHandler(EchoService echoService) {
        this.echoService = echoService;
    }

    @Override
    public void afterConnectionEstablished(WebSocketSession session) throws Exception {
        System.out.println("连接建立");
    }

    @Override
    public void handleTransportError(WebSocketSession session, Throwable exception) throws Exception {
        session.close(CloseStatus.SERVER_ERROR);
    }

    @Override
    protected void handleTextMessage(WebSocketSession session, TextMessage message) throws Exception {
        String echoMessage = echoService.getMessage(message.getPayload());
        session.sendMessage(new TextMessage(echoMessage));
    }
}

最后对所有的类进行配置，注意添加@EnableWebSocket注解和实现WebSocketConfigurer：

/**
 * @author yangfan
 * @date 2019/11/23
 */
@Configuration
@EnableWebSocket
public class WebSocketConfig implements WebSocketConfigurer {

    @Override
    public void registerWebSocketHandlers(WebSocketHandlerRegistry registry) {
        registry.addHandler(webSocketHandler(), "/echo").setAllowedOrigins("*");
    }

    @Bean
    public EchoService echoService() {
        return new DefaultEchoService("You said \"%s\"");
    }

    @Bean
    public WebSocketHandler webSocketHandler() {
        return new EchoWebSocketHandler(echoService());
    }
}

测试页面

http://www.websocket.org/echo.html

SpringBoot单元测试

SpringBoot为单元测试提供了非常方便的集成，引入依赖：

'org.springframework.boot:spring-boot-starter-test'

编写单元测试类：

/**
 * @author yangfan
 * @date 2019/11/23
 */
@RunWith(SpringRunner.class)
@SpringBootTest
public class MyControllerTest {

    @Autowired
    private WebApplicationContext webApplicationContext;

    private MockMvc mockMvc;

    @Before
    public void setUpMockMvc() {
        mockMvc = MockMvcBuilders.webAppContextSetup(webApplicationContext).build();
    }

    @Test
    public void testGetPerson() throws Exception {
        mockMvc.perform(MockMvcRequestBuilders.get("/api/person")
                .contentType(MediaType.APPLICATION_JSON_UTF8)
                .accept(MediaType.APPLICATION_JSON_UTF8))
                .andExpect(MockMvcResultMatchers.status().isOk())
                .andDo(MockMvcResultHandlers.print());
    }
}

控制台输出结果：

MockHttpServletRequest:
      HTTP Method = GET
      Request URI = /api/person
       Parameters = {}
          Headers = [Content-Type:"application/json;charset=UTF-8", Accept:"application/json;charset=UTF-8"]
             Body = null
    Session Attrs = {}

Handler:
             Type = com.test.springlecture.controller.MyController
           Method = public com.test.springlecture.domain.Person com.test.springlecture.controller.MyController.getPerson()

Async:
    Async started = false
     Async result = null

Resolved Exception:
             Type = null

ModelAndView:
        View name = null
             View = null
            Model = null

FlashMap:
       Attributes = null

MockHttpServletResponse:
           Status = 200
    Error message = null
          Headers = [Content-Type:"application/json;charset=UTF-8"]
     Content type = application/json;charset=UTF-8
             Body = {"id":18,"name":"张三","birthday":"2019-11-23T09:59:18.761+0000"}
    Forwarded URL = null
   Redirected URL = null
          Cookies = []

SpringBoot重要组件就介绍到这里，后面的文章会介绍Apache kafka的使用以及和SpringBoot应用的集成。

本文涉及到的源码：https://github.com/sail-y/spring-cloud-lecture/tree/master/spring-lecture