[开发测试]单元测试Mock工具TestableMock使用

单元测试原则

单元测试必须遵循AIR（Automatic, Independent, Repeatable）原则：单元测试在线上运行时，感觉像空气（AIR）一样感觉不到，但在测试质量的保障上，却是非常关键的。好的单元测试宏观上来说，具有自动化、独立性、可重复执行的特点。

• Automatic（自动化）：单元测试应该是全自动执行的，并且非交互式的。测试用例通常是被定期执行的，执行过程必须完全自动化才有意义。输出结果需要人工检查的测试不是一个好的单元测试。单元测试中禁止使用System.out来进行人肉验证，必须使用assert来验证。
• Independent（独立性）：保持单元测试的独立性。为了保证单元测试稳定可靠且便于维护，单元测试用例之间决不能互相调用，也不能依赖执行的先后次序。
• Repeatable（可重复）：单元测试是可以重复执行的，不能受到外界环境的影响。单元测试通常会被放到持续集成中，每次有代码check in时单元测试都会被执行。如果单测对外部环境（网络、服务、中间件等）有依赖，容易导致持续集成机制的不可用。

Mock工具对比

目前主要的Mock工具主要有Mockito、Spock、PowerMock和JMockit等，基本差异如下：

本文以TestableMock为例，针对单元测试中常出现的几种场景进行测试。

TestableMock 官方文档：https://alibaba.github.io/testable-mock/#/

TestableMock GitHub地址：https://github.com/alibaba/testable-mock

备注：单元测试基础学习：https://www.yuque.com/atguigu/springboot/ksndgx

本文使用代码样例环境：Spring Boot 2.5.7、TestableMock 0.70、MySQL 5.7.32、MyBatis 2.2.0、H2 1.4.200等，详见pom.xml文件

数据初始化准备

创建数据库goodsdb，创建表并初始化数据：

DROP TABLE IF EXISTS book_t;
CREATE TABLE book_t (
  book_id int(11) AUTO_INCREMENT PRIMARY KEY,
  book_name varchar(32) NOT NULL,
  book_price decimal(5,2) NOT NULL
);
INSERT INTO book_t VALUES (1, '安徒生童话', 99.99);
INSERT INTO book_t VALUES (2, 'MySQL实战教程', 88.88);

创建SpringBoot项目

官方地址：https://start.spring.io/

pom.xml文件如下：

<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 https://maven.apache.org/xsd/maven-4.0.0.xsd">
    <modelVersion>4.0.0</modelVersion>
    <parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>2.5.7</version>
        <relativePath/>
    </parent>
    <groupId>com.lwy.it</groupId>
    <artifactId>testablemock-demo</artifactId>
    <version>0.0.1-SNAPSHOT</version>
    <name>testablemock-demo</name>
    <description>Demo project for Spring Boot With TestableMock</description>
    <properties>
        <java.version>1.8</java.version>
        <testable.version>0.7.0</testable.version>
    </properties>
    <dependencies>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
        </dependency>
        <dependency>
            <groupId>org.mybatis.spring.boot</groupId>
            <artifactId>mybatis-spring-boot-starter</artifactId>
            <version>2.2.0</version>
        </dependency>
        <dependency>
            <groupId>mysql</groupId>
            <artifactId>mysql-connector-java</artifactId>
            <scope>runtime</scope>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-configuration-processor</artifactId>
            <optional>true</optional>
        </dependency>
        <dependency>
            <groupId>org.projectlombok</groupId>
            <artifactId>lombok</artifactId>
            <optional>true</optional>
        </dependency>

        <!-- 单元测试相关依赖-->
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-test</artifactId>
            <scope>test</scope>
        </dependency>
        <dependency>
            <groupId>com.alibaba.testable</groupId>
            <artifactId>testable-all</artifactId>
            <version>${testable.version}</version>
            <scope>test</scope>
        </dependency>
        <!-- 内存数据库，用于Mock MySQL-->
        <dependency>
            <groupId>com.h2database</groupId>
            <artifactId>h2</artifactId>
            <version>1.4.200</version>
            <scope>test</scope>
        </dependency>
    </dependencies>

    <build>
        <plugins>
            <plugin>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-maven-plugin</artifactId>
                <configuration>
                    <excludes>
                        <exclude>
                            <groupId>org.projectlombok</groupId>
                            <artifactId>lombok</artifactId>
                        </exclude>
                    </excludes>
                </configuration>
            </plugin>
            <plugin>
                <groupId>org.apache.maven.plugins</groupId>
                <artifactId>maven-surefire-plugin</artifactId>
                <configuration>
                    <argLine>
                        -javaagent:${settings.localRepository}/com/alibaba/testable/testable-agent/${testable.version}/testable-agent-${testable.version}.jar
                    </argLine>
                </configuration>
            </plugin>
            <!-- 插件介绍：http://maven.apache.org/surefire/maven-surefire-report-plugin/ -->
            <plugin>
                <groupId>org.apache.maven.plugins</groupId>
                <artifactId>maven-surefire-report-plugin</artifactId>
                <version>3.0.0-M5</version>
                <configuration>
                    <outputDirectory>${basedir}/target/report</outputDirectory>
                </configuration>
            </plugin>
        </plugins>
    </build>

</project>

代码结构

本文采用MVC结构：

创建ResultVO对象，用于封装返回结果给前端：

package com.lwy.it;

import lombok.Data;

import java.io.Serializable;
import java.util.List;

@Data
public class ResultVO<T> implements Serializable {
    private List<T> data;
    private String message;

    public ResultVO() {
    }

    public ResultVO(List<T> data) {
        this.data = data;
    }

    public ResultVO(List<T> data, String message) {
        this.data = data;
        this.message = message;
    }
}

vo对象：BookVO

package com.lwy.it.book.vo;

import lombok.Data;

import java.io.Serializable;

@Data
public class BookVO implements Serializable {
    private Integer bookId;
    private String bookName;
    private Double bookPrice;
}

控制器层controller对象：BookController

package com.lwy.it.book.controller;

import com.lwy.it.ResultVO;
import com.lwy.it.book.service.BookService;
import com.lwy.it.book.vo.BookVO;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.RestController;

import java.util.Arrays;

@RestController
public class BookController {

    @Autowired
    private BookService bookService;

    @GetMapping("/books")
    public ResultVO<BookVO> findAllBook() {
        return bookService.getAllBook();
    }

    /**
     * 用于模拟远程服务，通过RestTemplate调用
     * 接口服务地址：http://localhost:8080/mock/book
     *
     * @return ResultVO<BookVO>
     */
    @GetMapping("/book")
    public ResultVO<BookVO> exclusiveBook() {
        BookVO bookVO = new BookVO();
        bookVO.setBookId(100000);
        bookVO.setBookName("专属丛书：十万个为什么");
        bookVO.setBookPrice(998d);
        ResultVO<BookVO> resultVO = new ResultVO<>(Arrays.asList(bookVO));
        resultVO.setMessage("获取专属丛书成功");
        return resultVO;
    }

}

服务层service对象：BookService

package com.lwy.it.book.service;

import com.lwy.it.ResultVO;
import com.lwy.it.book.configuration.BookConfiguration;
import com.lwy.it.book.dao.BookDao;
import com.lwy.it.book.vo.BookVO;
import com.lwy.it.utils.DataUtils;
import lombok.extern.slf4j.Slf4j;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.core.ParameterizedTypeReference;
import org.springframework.http.HttpMethod;
import org.springframework.http.HttpStatus;
import org.springframework.http.ResponseEntity;
import org.springframework.stereotype.Service;
import org.springframework.web.client.RestTemplate;

import java.util.List;
import java.util.Objects;

@Slf4j
@Service
public class BookService {

    @Autowired
    private BookDao bookDao;

    @Autowired
    private BookConfiguration bookConfiguration;

    @Autowired
    private RestTemplate restTemplate;

    public ResultVO<BookVO> getAllBook() {
        List<BookVO> list = bookDao.getAllBook();
        ResultVO<BookVO> resultVO = DataUtils.convert(list);
        // 调用私有方法
        ResultVO<BookVO> vo = this.getExclusiveBook();
        log.info("获取到远程服务结果为：{}", vo);
        return resultVO;
    }

    // 用于模拟远程服务接口获取数据过程
    private ResultVO<BookVO> getExclusiveBook() {
        ResultVO<BookVO> resultVO = null;
        String url = bookConfiguration.getServerUrl();
        log.info("获取到的配置服务URL地址为：{}", url);
        // 返回结果是泛型类型，使用ParameterizedTypeReference进行包装
        ParameterizedTypeReference<ResultVO<BookVO>> reference = new ParameterizedTypeReference<ResultVO<BookVO>>() {
        };
        ResponseEntity<ResultVO<BookVO>> responseEntity = restTemplate.exchange(url, HttpMethod.GET, null, reference);
        if (Objects.equals(responseEntity.getStatusCode(), HttpStatus.OK)) {
            resultVO = responseEntity.getBody();
            log.info("获取到的结果为：{}", resultVO);
        } else {
            log.error("获取数据失败");
        }
        return resultVO;
    }
}

备注：RestTemplate基础学习：https://mp.weixin.qq.com/s/jIZCFOW4iy0j-epKVKQpOQ

数据库持久层dao对象：BookDao

package com.lwy.it.book.dao;

import com.lwy.it.book.vo.BookVO;
import org.apache.ibatis.annotations.Mapper;

import java.util.List;

@Mapper
public interface BookDao {
    List<BookVO> getAllBook();
}

对应mapper文件：book.mysql.xml

<?xml version="1.0" encoding="UTF-8" ?>
<!DOCTYPE mapper PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN" "http://mybatis.org/dtd/mybatis-3-mapper.dtd">
<mapper namespace="com.lwy.it.book.dao.BookDao">
    <select id="getAllBook" resultType="com.lwy.it.book.vo.BookVO">
        SELECT
            book_id AS bookId,
            book_name AS bookName,
            book_price AS bookPrice
        FROM
            book_t
    </select>
</mapper>

相关配置信息

application.properties

server.port=8080

server.servlet.context-path=/mock

#MyBatis配置
mybatis.configuration.map-underscore-to-camel-case=true
mybatis.mapper-locations=classpath:mapper/*.xml

#MySQL配置
spring.datasource.url=jdbc:mysql://localhost:3306/goodsdb?allowMultiQueries=true&serverTimezone=GMT&characterEncoding=utf8
spring.datasource.driver-class-name=com.mysql.cj.jdbc.Driver
spring.datasource.username=root
spring.datasource.password=123456

#配置远程服务地址
book.server.url=${bookUrl}

创建配置类，用于接收book.server.url变量参数，BookConfiguration

package com.lwy.it.book.configuration;

import lombok.Data;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.boot.web.client.RestTemplateBuilder;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.web.client.RestTemplate;

@Data
@Configuration
public class BookConfiguration {

    @Value("${book.server.url}")
    private String serverUrl;

    @Bean
    public RestTemplate restTemplate(RestTemplateBuilder builder) {
        return builder.build();
    }

}

工具类：DataUtils

package com.lwy.it.utils;

import com.lwy.it.ResultVO;
import org.springframework.util.CollectionUtils;

import java.util.Collections;
import java.util.List;

public class DataUtils {

    /**
     * 用于数据包装转换
     *
     * @param list 泛型结合
     * @param <T>  泛型类型
     * @return ResultVO<T>
     */
    public static <T> ResultVO<T> convert(List<T> list) {
        ResultVO<T> resultVO = new ResultVO<>();
        if (CollectionUtils.isEmpty(list)) {
            resultVO.setData(Collections.emptyList());
            resultVO.setMessage("数据为空");
        } else {
            resultVO.setData(list);
            resultVO.setMessage("数据不为空");
        }
        return resultVO;
    }

}

以上为服务的相关代码，均在src/main目录下面的目录中。

启动服务（要添加环境变量参数：bookUrl=http://localhost:8080/mock/book）：访问http://localhost:8080/mock/books，得到数据库中数据：

{"data":[{"bookId":1,"bookName":"安徒生童话","bookPrice":99.99},{"bookId":2,"bookName":"MySQL实战教程","bookPrice":88.88}],"message":"数据不为空"}

编写单元测试代码

单元测试文件均位于在src/test目录下：

数据持久层单元测试

对于Dao层（数据库相关的查询，更新，删除等）操作，使用嵌入式内存数据库H2 Database验证逻辑。和数据库相关的单元测试，不给数据库造成脏数据。不能假设数据库里的数据是存在的，或者直接操作数据库把数据插入进去，请使用程序插入或者导入数据的方式来准备数据。 反例：删除某一行数据的单元测试，在数据库中，先直接手动增加一行作为删除目标，但是这一行新增数据并不符合业务插入规则，导致测试结果异常。

针对BookDao访问数据库进行单元测试，需要在src/test/resources目录下新建application.properties文件，内容如下

server.port=8080
server.servlet.context-path=/mock
#MyBatis配置
mybatis.configuration.map-underscore-to-camel-case=true
mybatis.mapper-locations=classpath:mapper/*.xml

########################数据更改###########################
#内存数据库H2以MYSQL模式运行，初始化时执行classpath:initdb.sql脚本，详情参考：http://www.h2database.com/html/features.html
spring.datasource.url=jdbc:h2:mem:goodsdb;MODE=MYSQL;INIT=RUNSCRIPT FROM 'classpath:initdb.sql'
spring.datasource.driver-class-name=org.h2.Driver
spring.datasource.username=
spring.datasource.password=
#########################数据更改##########################

#自定义变量配置
book.server.url=${bookUrl}

H2数据库初始化脚本initdb.sql文件如下：

DROP TABLE IF EXISTS book_t;
CREATE TABLE book_t (
                        book_id int(11) AUTO_INCREMENT PRIMARY KEY,
                        book_name varchar(32) NOT NULL,
                        book_price decimal(5,2) NOT NULL,
                        PRIMARY KEY (book_id)
);

INSERT INTO book_t VALUES (1, '测试数据1', 99.99);
INSERT INTO book_t VALUES (2, '测试数据2', 88.88);
INSERT INTO book_t VALUES (3, '测试数据2', 77.77);
INSERT INTO book_t VALUES (4, '测试数据2', 66.66);
INSERT INTO book_t VALUES (5, '测试数据2', 55.55);
INSERT INTO book_t VALUES (6, '测试数据2', 44.44);

BookDao对应单元测试BookDaoTest代码如下（包路径一致）：

package com.lwy.it.book.dao;

import com.lwy.it.book.vo.BookVO;
import lombok.extern.slf4j.Slf4j;
import org.junit.jupiter.api.DisplayName;
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.junit.jupiter.api.Assertions.assertEquals;

@Slf4j
@SpringBootTest
public class BookDaoTest {

    @Autowired
    private BookDao bookDao;

    @Test
    @DisplayName("getAllBook")
    public void getAllBook_test() {
        List<BookVO> list = bookDao.getAllBook();
        log.info("结果为：{}", list);
        assertEquals(6, list.size());
    }
}

启动测试方法（要添加环境变量参数：bookUrl=http://localhost:8080/mock/book），日志如下，执行成功。我们发现数据被H2数据库中我们初始化的数据进行了替代。

2021-12-01 16:25:31.458  INFO 21644 --- [           main] com.zaxxer.hikari.HikariDataSource       : HikariPool-1 - Starting...
2021-12-01 16:25:31.919  INFO 21644 --- [           main] com.zaxxer.hikari.HikariDataSource       : HikariPool-1 - Start completed.
2021-12-01 16:25:31.983  INFO 21644 --- [           main] com.lwy.it.book.dao.BookDaoTest          : 结果为：[BookVO(bookId=1, bookName=测试数据1, bookPrice=99.99), BookVO(bookId=2, bookName=测试数据2, bookPrice=88.88), BookVO(bookId=3, bookName=测试数据2, bookPrice=77.77), BookVO(bookId=4, bookName=测试数据2, bookPrice=66.66), BookVO(bookId=5, bookName=测试数据2, bookPrice=55.55), BookVO(bookId=6, bookName=测试数据2, bookPrice=44.44)]

服务层单元测试

因为前面场景服务层依赖外部服务等，测试案例应不依赖环境，所以我们需要把依赖Mock掉

我们使用TestableMock工具，按照官方文档进行操作：https://alibaba.github.io/testable-mock/#/

备注：这里的版本我们使用0.7.x版本，<testable.version>0.7.0</testable.version>，对应泛型Mock更加便捷。

单元测试代码如下：

package com.lwy.it.book.service;

import com.alibaba.testable.core.annotation.MockInvoke;
import com.alibaba.testable.core.tool.PrivateAccessor;
import com.lwy.it.ResultVO;
import com.lwy.it.book.dao.BookDao;
import com.lwy.it.book.vo.BookVO;
import com.lwy.it.utils.DataUtils;
import lombok.extern.slf4j.Slf4j;
import org.junit.jupiter.api.DisplayName;
import org.junit.jupiter.api.Test;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.test.context.SpringBootTest;
import org.springframework.core.ParameterizedTypeReference;
import org.springframework.http.HttpEntity;
import org.springframework.http.HttpMethod;
import org.springframework.http.HttpStatus;
import org.springframework.http.ResponseEntity;
import org.springframework.lang.Nullable;
import org.springframework.web.client.RestClientException;
import org.springframework.web.client.RestTemplate;

import java.util.ArrayList;
import java.util.Collections;
import java.util.List;

import static org.junit.jupiter.api.Assertions.assertEquals;
import static org.junit.jupiter.api.Assertions.assertNull;

@Slf4j
@SpringBootTest
public class BookServiceTest {

    @Autowired
    private BookService bookService;

    // 前置步骤，准备Mock容器
    public static class Mock {
        // 放置Mock方法的地方，按照官方示例 把Mock方法访问控制都改成private

        /**
         * 静态方法&泛型类型方法进行Mock
         * DataUtils类中public static <T> ResultVO<T> convert(List<T> list)
         *
         * @param list 泛型集合
         * @param <T>  泛型类型
         * @return ResultVO<T>
         */
        @MockInvoke(targetClass = DataUtils.class)
        private static <T> ResultVO<T> convert(List<T> list) {
            log.info("~~~~~~泛型&静态方法被执行~~~~~~");
            return new ResultVO<>(Collections.emptyList());
        }

        /**
         * Mock掉数据访问层BookDao的List<BookVO> getAllBook()方法
         *
         * @return List<BookVO>
         */
        @MockInvoke(targetClass = BookDao.class)
        private List<BookVO> getAllBook() {
            BookVO bookVO = new BookVO();
            bookVO.setBookId(10000);
            bookVO.setBookName("测试数据");
            bookVO.setBookPrice(99.99d);
            log.info("~~~~~~Dao层访问被Mock替代~~~~~~");
            return new ArrayList<BookVO>() {{
                add(bookVO);
            }};
        }

        /**
         * BookService getExclusiveBook()方法中调用RestTemplate的方法，外部依赖需要Mock掉
         * public <T> ResponseEntity<T> exchange(String url, HttpMethod method, @Nullable HttpEntity<?> requestEntity, ParameterizedTypeReference<T> responseType, Object... uriVariables) throws RestClientException
         *
         * @param url           访问url
         * @param method        get/post访问方式等
         * @param requestEntity 请求参数
         * @param responseType  返回类型（因为涉及泛型）
         * @param uriVariables
         * @param <T>           泛型类型
         * @return
         * @throws RestClientException
         */
        @MockInvoke(targetClass = RestTemplate.class)
        private <T> ResponseEntity<T> exchange(String url, HttpMethod method, @Nullable HttpEntity<?> requestEntity,
                                               ParameterizedTypeReference<T> responseType, Object... uriVariables) throws RestClientException {
            log.info("~~~~~~调用RestTemplate方法被Mock替代~~~~~~");
            return new ResponseEntity<T>(HttpStatus.OK);
        }
    }

    @Test
    @DisplayName("public方法：getAllBook单元测试")
    public void getAllBook_test() {
        ResultVO<BookVO> resultVO = bookService.getAllBook();
        log.info("ResultVO结果为：{}", resultVO);
        assertEquals(0, resultVO.getData().size());

    }

    /**
     * 对私有方法进行单元测试
     */
    @Test
    @DisplayName("private方法：getExclusiveBook单元测试")
    public void getExclusiveBook_test() {
        ResultVO<BookVO> resultVO = PrivateAccessor.invoke(bookService, "getExclusiveBook");
        log.info("ResultVO结果为：{}", resultVO);
        assertNull(resultVO);
    }

}

执行验证逻辑：

执行getAllBook_test测试用例（要添加环境变量参数：bookUrl=http://localhost:8080/mock/book），结果如下，实际调用过程中被替代

2021-12-01 16:56:32.623  INFO 23380 --- [           main] com.lwy.it.book.service.BookServiceTest  : ~~~~~~Dao层访问被Mock替代~~~~~~
2021-12-01 16:56:32.625  INFO 23380 --- [           main] com.lwy.it.book.service.BookServiceTest  : ~~~~~~泛型&静态方法被执行~~~~~~
2021-12-01 16:56:32.625  INFO 23380 --- [           main] com.lwy.it.book.service.BookService      : 获取到的配置服务URL地址为：http://localhost:8080/mock/book
2021-12-01 16:56:32.628  INFO 23380 --- [           main] com.lwy.it.book.service.BookServiceTest  : ~~~~~~调用RestTemplate方法被Mock替代~~~~~~
2021-12-01 16:56:32.638  INFO 23380 --- [           main] com.lwy.it.book.service.BookService      : 获取到的结果为：null
2021-12-01 16:56:32.638  INFO 23380 --- [           main] com.lwy.it.book.service.BookService      : 获取到远程服务结果为：null
2021-12-01 16:56:32.638  INFO 23380 --- [           main] com.lwy.it.book.service.BookServiceTest  : ResultVO结果为：ResultVO(data=[], message=null)

执行getExclusiveBook_test测试用例（要添加环境变量参数：bookUrl=http://localhost:8080/mock/book），结果如下，实际调用过程中被替代

2021-12-01 17:08:10.378  INFO 7740 --- [           main] com.lwy.it.book.service.BookService      : 获取到的配置服务URL地址为：http://localhost:8080/mock/book
2021-12-01 17:08:10.383  INFO 7740 --- [           main] com.lwy.it.book.service.BookServiceTest  : ~~~~~~调用RestTemplate方法被Mock替代~~~~~~
2021-12-01 17:08:10.394  INFO 7740 --- [           main] com.lwy.it.book.service.BookService      : 获取到的结果为：null
2021-12-01 17:08:10.394  INFO 7740 --- [           main] com.lwy.it.book.service.BookServiceTest  : ResultVO结果为：null

执行所有测试用例：

mvn clean test -DbookUrl=http://localhost:8080/mock/book
若涉及多profile文件，则添加-P参数

执行所有测试用例并生成报告：

mvn clean surefire-report:report -DbookUrl=http://localhost:8080/mock/book

在target/report/（pom.xml文件配置的${basedir}/target/report）目录下生成了surefire-report.html文件，用浏览器打开即可。

如果需要覆盖率信息，则需要使用Jacoco。