COLA常用组件

A BiliBili video

Maven依赖

• pom.xml

    <properties>
        <cola.components.version>5.0.0</cola.components.version>
    </properties>

    <!-- 版本管理 -->
    <dependencyManagement>
        <dependencies>
            <dependency>
                <groupId>com.alibaba.cola</groupId>
                <artifactId>cola-components-bom</artifactId>
                <version>${cola.components.version}</version>
                <type>pom</type>
                <scope>import</scope>
            </dependency>
        </dependencies>
    </dependencyManagement>

    <!-- 组件 -->
    <dependencies>
        <dependency>
            <groupId>com.alibaba.cola</groupId>
            <artifactId>cola-component-dto</artifactId>
        </dependency>
        <dependency>
            <groupId>com.alibaba.cola</groupId>
            <artifactId>cola-component-exception</artifactId>
        </dependency>
        <dependency>
            <groupId>com.alibaba.cola</groupId>
            <artifactId>cola-component-catchlog-starter</artifactId>
        </dependency>
        <dependency>
            <groupId>com.alibaba.cola</groupId>
            <artifactId>cola-component-domain-starter</artifactId>
        </dependency>
        <dependency>
            <groupId>com.alibaba.cola</groupId>
            <artifactId>cola-component-extension-starter</artifactId>
        </dependency>
        <dependency>
            <groupId>com.alibaba.cola</groupId>
            <artifactId>cola-component-statemachine</artifactId>
        </dependency>
        <dependency>
            <groupId>com.alibaba.cola</groupId>
            <artifactId>cola-component-test-container</artifactId>
        </dependency>

      <!-- ruleengine -->
    </dependencies>

dto

• 规范请求参数、规范响应结果，Api对接统一处理

        <dependency>
            <groupId>com.alibaba.cola</groupId>
            <artifactId>cola-component-dto</artifactId>
        </dependency>

请求

Query/Command

• Query类中没有任何字段，仅标识读数据请求

@Data
@EqualsAndHashCode(callSuper = true)
public class UserFindQry extends Query {
    @Parameter(title = "姓名(模糊搜索)")
    private String name;
}

• Command类中没有任何字段，仅标识写数据请求

@Data
@EqualsAndHashCode(callSuper = true)
public class UserAddCmd extends Command {
    @Schema(title = "姓名")
    @NotBlank(message = "name不能为空")
    private String name;

    @Schema(title = "性别")
    @NotEmpty(message = "sex不能为空")
    private Sex sex;

    @Schema(title = "密码")
    @NotBlank(message = "password不能为空")
    private String password;
}

PageQuery

• PageQuery是分页请求，包含了分页需要的字段
  • int pageIndex: 页码，默认1
  • int pageSize: 页面大小，默认10
  • String orderBy: 排序字段
  • String orderDirection: 排序方向，"ASC"/"DESC"
  • String groupBy: 分组
  • boolean needTotalCount: 是否显示总行数

@Data
@EqualsAndHashCode(callSuper = true)
public class UserPageQry extends PageQuery {
    @Parameter(description = "姓名")
    private String name;

    @Parameter(description = "性别")
    private Sex sex;
}

响应

• Response是所有响应类的基类，理论上返回值都可以用Response
• 但是建议写成"SingleResponse<...>"这样的子类，Swagger文档生成的响应值更加明确，有利于团队协作

Response

• 响应结果，所有响应的基类，即所有响应必定有以下字段
• 其他系统对接时做统一解析
  • HTTP对接，使用状态码判断结果
  • RPC对接，使用"success"判断结果

{
  "success": true,
  "errCode": "string",
  "errMessage": "string"
}

• 示例：无需返回值的结果

    public Response delete(Long id) {
        // 直接响应成功
        return Response.buildSuccess();

        // 可直接响应失败，但一般用在异常处理中，配合响应码使用
        // return Response.buildFailure("UNKNOWN_ERROR","错误信息");
    }

SingleResponse

• 返回一个对象，格式如下

{
  "success": true,
  "errCode": null,
  "errMessage": null,
  "data": null
}

• 示例：返回用户详情

    public SingleResponse<UserDetailCO> getDetail(Long id) {
        UserDetailCO detailCO = ...;
        // 返回一个对象结果
        return SingleResponse.of(detailCO);
    }

MultiResponse

• 返回列表，格式如下

{
  "success": true,
  "errCode": null,
  "errMessage": null,
  "empty": true,
  "notEmpty": false,
  "data": []
}

• 示例：返回所有用户

    public MultiResponse<UserDetailCO> getAll() {
        List<UserDetailCO> allUser = userService.getAll();
        return MultiResponse.of(allUser);
    }

PageResponse

• 返回分页信息，格式如下

{
  "success": true,
  "errCode": null,
  "errMessage": null,
  "empty": true,
  "notEmpty": false,
  "pageIndex": 1,
  "pageSize": 10,
  "totalPages": 0,
  "totalCount": 0,
  "data": []
}

• 示例：返回用户分页

    public PageResponse<UserPageCO> getPage(UserPageQry qry) {
        List<UserPageCO> list = ...;
        int totalCount = ...;
        return PageResponse.of(list, totalCount, qry.getPageSize(), qry.getPageIndex());
    }

exception

• 官网定义：https://github.com/alibaba/COLA/tree/master/cola-components/cola-component-exception
  • BizException: 业务异常，有明确业务语义，不需要记录Error日志，不需要Retry
    • 如：请求参数错误，账户余额不足等
  • SysException: 已知的系统异常，需要记录Error日志，可以Retry
    • 如：数据库无法连接，RPC调用失败等
  • Exception: 未知的其它异常，需要完整的Error Stack日志，可以Retry

        <dependency>
            <groupId>com.alibaba.cola</groupId>
            <artifactId>cola-component-exception</artifactId>
        </dependency>

业务抛出异常

• 使用COLA中的Assert抛出BizException异常

import com.alibaba.cola.exception.BizException;
import com.alibaba.cola.exception.SysException;
import com.alibaba.cola.exception.Assert;


// 直接抛出异常
throw new BizException("这里写业务错误信息");
throw new BizException("UNKNOWN_ERROR","这里写业务错误信息");

throw new SysException("这里写系统错误信息");
throw new SysException("SYSTEM_ERROR","这里写系统错误信息");

// Assert不通过时，抛出BizException异常
Assert.isFalse(user == null, "user不能为null");
// 自定义错误码，默认错误码是"BIZ_ERROR"
Assert.isFalse(user == null, "DATA_NOR_FOUND_ERROR", "user不能为null");

全局异常捕捉

@Slf4j
@RestControllerAdvice
public class GlobalExceptionHandler {

    @ResponseBody
    @ResponseStatus(HttpStatus.BAD_REQUEST)
    @ExceptionHandler(BizException.class)
    public Response handleBizException(BizException e) {
        // 业务异常，无需记录日志
        return Response.buildFailure(e.getErrCode(), e.getMessage());
    }

    @ResponseBody
    @ResponseStatus(HttpStatus.BAD_REQUEST)
    @ExceptionHandler(SysException.class)
    public Response handleSysException(SysException e) {
        // 已知系统异常，打印报错信息
        log.warn("已知系统异常：{} {}", e.getErrCode(), e.getMessage());
        return Response.buildFailure(e.getErrCode(), e.getMessage());
    }

    @ResponseBody
    @ResponseStatus(HttpStatus.BAD_REQUEST)
    @ExceptionHandler(Exception.class)
    public Response handleException(Exception e) {
        // 未知系统异常，打印堆栈信息
        log.error("未知系统异常： {}", e.getMessage(), e);
        return Response.buildFailure("UNKNOWN_ERROR", e.getMessage());
    }
}

catchlog-starter

• 使用aop打印方法入参出参，以及耗时
• 官方说明：https://github.com/alibaba/COLA/tree/master/cola-components/cola-component-catchlog-starter
• @CatchAndLog注解在类上
• 注意fastjson的版本，是fastjson的2.x版本，而不是fastjson2

        <!-- cola示例放在app包 -->
        <dependency>
            <groupId>com.alibaba.cola</groupId>
            <artifactId>cola-component-catchlog-starter</artifactId>
        </dependency>

        <!-- 打印日志依赖fastjson-2.x版本，底层为fastjson2的兼容版本 -->
        <dependency>
            <groupId>com.alibaba</groupId>
            <artifactId>fastjson</artifactId>
            <version>2.0.51</version>
        </dependency>

• 入口类增加扫描配置"com.alibaba.cola"

@SpringBootApplication(scanBasePackages = {"com.xxc.demo", "com.alibaba.cola"})
public class Application {
    public static void main(String[] args) {
        SpringApplication.run(Application.class, args);
    }
}

• start/resource/logback-spring.xml
  • 日志级别为"DEBUG"

<!-- 日志记录组件的日志 -->
<logger name="com.alibaba.cola.catchlog" level="DEBUG" />

• 需要的类中注解
  • @CatchAndLog注解在类上，因为aop匹配使用@within()，匹配类注解

// 或者放在Controller层
@CatchAndLog	// aop匹配使用@within，匹配类注解
public class UserServiceImpl implements UserService{
    // ...
}

• 打印日志示例如下
  • 打印请求参数、响应解雇、耗时

# 正常响应日志
DEBUG c.alibaba.cola.catchlog.CatchLogAspect   : START PROCESSING: UserServiceImpl.getPage(..)
DEBUG c.alibaba.cola.catchlog.CatchLogAspect   : REQUEST: {"pageIndex":1,"pageSize":10}
#...其他日志
DEBUG c.alibaba.cola.catchlog.CatchLogAspect   : RESPONSE: {"data":{"current":1,"pages":0,"records":[{"age":18,"id":1,"name":"老王"},{"age":18,"id":2,"name":"老王"},{"age":0,"id":3,"name":"string"}],"size":10,"total":0},"success":true}
DEBUG c.alibaba.cola.catchlog.CatchLogAspect   : COST: 520ms


# 报错日志
DEBUG c.alibaba.cola.catchlog.CatchLogAspect   : START PROCESSING: UserServiceImpl.getPage(..)
DEBUG c.alibaba.cola.catchlog.CatchLogAspect   : REQUEST: {"pageIndex":1,"pageSize":10}
WARN c.alibaba.cola.catchlog.CatchLogAspect   : BIZ EXCEPTION : 故意报错
ERROR c.alibaba.cola.catchlog.CatchLogAspect   : 故意报错
# ...报错堆栈
WARN c.a.c.catchlog.ApplicationContextHelper  : No bean found for com.alibaba.cola.catchlog.ResponseHandlerI
DEBUG c.alibaba.cola.catchlog.CatchLogAspect   : RESPONSE: {"errCode":"BIZ_ERROR","errMessage":"故意报错","success":false}
DEBUG c.alibaba.cola.catchlog.CatchLogAspect   : COST: 227ms

domain-starter

• 使用@Entity注解scope为"prototype"的Bean
• DomainFactory实例化Bean

        <!-- cola archetypes生成 -->
        <dependency>
            <groupId>com.alibaba.cola</groupId>
            <artifactId>cola-component-domain-starter</artifactId>
        </dependency>

• 入口类增加扫描配置"com.alibaba.cola"

@SpringBootApplication(scanBasePackages = {"com.xxc.demo", "com.alibaba.cola"})
public class Application {
    public static void main(String[] args) {
        SpringApplication.run(Application.class, args);
    }
}

• 注解为@Entity，scope为"prototype"的Bean

import com.alibaba.cola.domain.Entity;

@Entity
public class Heartbeat{
    // ...
}

• 使用DomainFactory实例化一个对象

@Component
public class HeartbeatExe{
    @Async
    public void execute(){
        // 获取新对象
        Heartbeat heartbeat = DomainFactory.create(Heartbeat.class);
        //...
    }
}