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OJ在线评测系统 后端基础部分开发 完善CRUD相关接口

完善相关接口

判斷编程语言是否合法

先从用户的请求拿到Language

package com.dduo.dduoj.service.impl;import com.baomidou.mybatisplus.core.conditions.query.QueryWrapper;
import com.baomidou.mybatisplus.extension.service.impl.ServiceImpl;
import com.dduo.dduoj.common.ErrorCode;
import com.dduo.dduoj.exception.BusinessException;
import com.dduo.dduoj.model.dto.questionsubmit.JudgeInfo;
import com.dduo.dduoj.model.dto.questionsubmit.QuestionSubmitAddRequest;
import com.dduo.dduoj.model.enums.QuestionSubmitLanguageEnum;
import com.dduo.dduoj.model.enums.QuestionSubmitStatusEnum;
import com.dduo.dduoj.service.mapper.QuestionSubmitMapper;
import com.dduo.dduoj.service.mapper.entity.Question;
import com.dduo.dduoj.service.mapper.entity.QuestionSubmit;
import com.dduo.dduoj.service.mapper.entity.User;
import com.dduo.dduoj.service.QuestionService;
import com.dduo.dduoj.service.QuestionSubmitService;
import javax.annotation.Resource;
import org.springframework.aop.framework.AopContext;
import org.springframework.stereotype.Service;
import org.springframework.transaction.annotation.Transactional;/*** 提交题目服务实现**/
@Service
public class QuestionSubmitServiceImpl extends ServiceImpl<QuestionSubmitMapper, QuestionSubmit>implements QuestionSubmitService {@Resourceprivate QuestionService questionService;/*** 提交题目** @param questionSubmitAddRequest* @param loginUser* @return*/@Overridepublic long doQuestionSubmit(QuestionSubmitAddRequest questionSubmitAddRequest, User loginUser) {// 编程语言是否合法String language = questionSubmitAddRequest.getLanguage();QuestionSubmitLanguageEnum enumByValue = QuestionSubmitLanguageEnum.getEnumByValue(language);if (enumByValue==null){throw new BusinessException(ErrorCode.PARAMS_ERROR,"编程语言错误");}long questionId = questionSubmitAddRequest.getQuestionId();// 判断实体是否存在,根据类别获取实体Question question = questionService.getById(questionId);if (question == null) {throw new BusinessException(ErrorCode.NOT_FOUND_ERROR);}// 是否提交题目long userId = loginUser.getId();// 每个用户串行提交题目// 锁必须要包裹住事务方法QuestionSubmit questionSubmit = new QuestionSubmit();questionSubmit.setUserId(userId);questionSubmit.setQuestionId(questionId);questionSubmit.setCode(questionSubmitAddRequest.getCode());questionSubmit.setLanguage(language);//设置初始状态questionSubmit.setStatus(QuestionSubmitStatusEnum.WATING.getValue());questionSubmit.setJudgeInfo("{}");boolean save = this.save(questionSubmit);if(!save){throw new BusinessException(ErrorCode.SYSTEM_ERROR,"数据插入失败");}return questionSubmit.getId();}}

写好了 idea启动

代码运行成功

我们

使用接口文档提交题目试一试

数据库中数据录入成功

为了防止用户根据id爬取题目

建议把id的生成规则改成ASSIGN_ID

非连续递增

而不是从1开始递增

数值传到数据库中进行一个转换

/*** 创建** @param questionAddRequest* @param request* @return*/
@PostMapping("/add")
public BaseResponse<Long> addQuestion(@RequestBody QuestionAddRequest questionAddRequest, HttpServletRequest request) {if (questionAddRequest == null) {throw new BusinessException(ErrorCode.PARAMS_ERROR);}Question question = new Question();BeanUtils.copyProperties(questionAddRequest, question);List<String> tags = questionAddRequest.getTags();if (tags != null) {question.setTags(GSON.toJson(tags));}List<JudgeCase> judgeCase = questionAddRequest.getJudgeCase();if (judgeCase != null) {question.setJudgeCase(GSON.toJson(judgeCase));}List<JudgeConfig> judgeConfig = questionAddRequest.getJudgeConfig();if (judgeConfig != null) {question.setJudgeConfig(GSON.toJson(judgeConfig));}questionService.validQuestion(question, true);User loginUser = userService.getLoginUser(request);question.setUserId(loginUser.getId());question.setFavourNum(0);question.setThumbNum(0);boolean result = questionService.save(question);ThrowUtils.throwIf(!result, ErrorCode.OPERATION_ERROR);long newQuestionId = question.getId();return ResultUtils.success(newQuestionId);
}

@PostMapping("/update")
@AuthCheck(mustRole = UserConstant.ADMIN_ROLE)
public BaseResponse<Boolean> updateQuestion(@RequestBody QuestionUpdateRequest questionUpdateRequest) {if (questionUpdateRequest == null || questionUpdateRequest.getId() <= 0) {throw new BusinessException(ErrorCode.PARAMS_ERROR);}Question question = new Question();BeanUtils.copyProperties(questionUpdateRequest, question);List<String> tags = questionUpdateRequest.getTags();if (tags != null) {question.setTags(GSON.toJson(tags));}List<JudgeCase> judgeCase = questionUpdateRequest.getJudgeCase();if (judgeCase != null) {question.setJudgeCase(GSON.toJson(judgeCase));}List<JudgeConfig> judgeConfig = questionUpdateRequest.getJudgeConfig();if (judgeConfig != null) {question.setJudgeConfig(GSON.toJson(judgeConfig));}// 参数校验questionService.validQuestion(question, false);long id = questionUpdateRequest.getId();// 判断是否存在Question oldQuestion = questionService.getById(id);ThrowUtils.throwIf(oldQuestion == null, ErrorCode.NOT_FOUND_ERROR);boolean result = questionService.updateById(question);return ResultUtils.success(result);
}

@PostMapping("/edit")
public BaseResponse<Boolean> editQuestion(@RequestBody QuestionEditRequest questionEditRequest, HttpServletRequest request) {if (questionEditRequest == null || questionEditRequest.getId() <= 0) {throw new BusinessException(ErrorCode.PARAMS_ERROR);}Question question = new Question();BeanUtils.copyProperties(questionEditRequest, question);List<String> tags = questionEditRequest.getTags();if (tags != null) {question.setTags(GSON.toJson(tags));}List<JudgeCase> judgeCase = questionEditRequest.getJudgeCase();if (judgeCase != null) {question.setJudgeCase(GSON.toJson(judgeCase));}List<JudgeConfig> judgeConfig = questionEditRequest.getJudgeConfig();if (judgeConfig != null) {question.setJudgeConfig(GSON.toJson(judgeConfig));}// 参数校验questionService.validQuestion(question, false);User loginUser = userService.getLoginUser(request);long id = questionEditRequest.getId();// 判断是否存在Question oldQuestion = questionService.getById(id);ThrowUtils.throwIf(oldQuestion == null, ErrorCode.NOT_FOUND_ERROR);// 仅本人或管理员可编辑if (!oldQuestion.getUserId().equals(loginUser.getId()) && !userService.isAdmin(loginUser)) {throw new BusinessException(ErrorCode.NO_AUTH_ERROR);}boolean result = questionService.updateById(question);return ResultUtils.success(result);
}

枯燥的测试

完善

查询提交信息

接口功能 能够根据用户id 题目id 编程语言 去查询提交记录

注意事项 仅本人和管理员能看见自己提交代码的答案 提交代码

实现方案 先查询

package com.dduo.dduoj.model.dto.questionsubmit;import com.baomidou.mybatisplus.annotation.TableField;
import lombok.Data;import java.io.Serializable;//查询请求
@Data
public class QuestionSubmitQueryRequest implements Serializable {/*** 编程语言*/private String language;    /*** 提交状态*/private Integer status;/*** 题目id*/private Long questionId;/*** 用户id*/private Long userId;@TableField(exist = false)private static final long serialVersionUID = 1L;
}

QuestionSubmitVO

/*** 包装类转对象** @param questionSubmitVO* @return*/
public static QuestionSubmit voToObj(QuestionSubmitVO questionSubmitVO) {if (questionSubmitVO == null) {return null;}QuestionSubmit questionSubmit = new QuestionSubmit();BeanUtils.copyProperties(questionSubmitVO, questionSubmit);JudgeInfo judgeInfoObj = questionSubmitVO.getJudgeInfo();if (judgeInfoObj != null) {questionSubmit.setJudgeInfo(JSONUtil.toJsonStr(judgeInfoObj));}return questionSubmit;
}/*** 对象转包装类** @param questionSubmit* @return*/
public static QuestionSubmitVO objToVo(QuestionSubmit questionSubmit) {if (questionSubmit == null) {return null;}QuestionSubmitVO questionSubmitVO = new QuestionSubmitVO();BeanUtils.copyProperties(questionSubmit, questionSubmitVO);String judgeInfoStr = questionSubmit.getJudgeInfo();questionSubmitVO.setJudgeInfo(JSONUtil.toBean(judgeInfoStr, JudgeInfo.class));return questionSubmitVO;
}

先查询再根据权限去脱敏

/*** 分页获取题目提交(除了管理员外 普通用户是能看见非答案 提交代码等非公开信息)** @param questionSubmitQueryRequest* @return*/
@PostMapping("/list/page")
@AuthCheck(mustRole = UserConstant.ADMIN_ROLE)
public BaseResponse<Page<QuestionSubmitVO>> listQuestionSubmitByPage(@RequestBody QuestionSubmitQueryRequest questionSubmitQueryRequest,HttpServletRequest request) {long current = questionSubmitQueryRequest.getCurrent();long size = questionSubmitQueryRequest.getPageSize();//从数据库中获取信息Page<QuestionSubmit> questionSubmitPage = questionSubmitService.page(new Page<>(current, size),questionSubmitService.getQueryWrapper(questionSubmitQueryRequest));//返回脱敏方法return ResultUtils.success(questionSubmitService.getQuestionSubmitVOPage(questionSubmitPage,request));
}

脱敏处理

/*
* 单条数据
* */
@Override
public QuestionSubmitVO getQuestionSubmitVO(QuestionSubmit questionSubmit, User loginUser) {QuestionSubmitVO questionSubmitVO = QuestionSubmitVO.objToVo(questionSubmit);// 脱敏:仅本人和管理员能看见自己(提交 userId 和登录用户 id 不同)提交的代码long userId = loginUser.getId();// 处理脱敏if (userId != questionSubmit.getUserId() && !userService.isAdmin(loginUser)) {questionSubmitVO.setCode(null);}return questionSubmitVO;
}/** 多条数据* */
@Override
public Page<QuestionSubmitVO> getQuestionSubmitVOPage(Page<QuestionSubmit> questionSubmitPage, User loginUser) {List<QuestionSubmit> questionSubmitList = questionSubmitPage.getRecords();Page<QuestionSubmitVO> questionSubmitVOPage = new Page<>(questionSubmitPage.getCurrent(), questionSubmitPage.getSize(), questionSubmitPage.getTotal());if (CollectionUtils.isEmpty(questionSubmitList)) {return questionSubmitVOPage;}List<QuestionSubmitVO> questionSubmitVOList = questionSubmitList.stream().map(questionSubmit -> getQuestionSubmitVO(questionSubmit, loginUser)).collect(Collectors.toList());questionSubmitVOPage.setRecords(questionSubmitVOList);return questionSubmitVOPage;
}

QuestionSubmitServiceImpl

package com.dduo.dduoj.service.impl;import com.baomidou.mybatisplus.core.conditions.query.QueryWrapper;
import com.baomidou.mybatisplus.extension.plugins.pagination.Page;
import com.baomidou.mybatisplus.extension.service.impl.ServiceImpl;
import com.dduo.dduoj.common.ErrorCode;
import com.dduo.dduoj.constant.CommonConstant;
import com.dduo.dduoj.exception.BusinessException;
import com.dduo.dduoj.judge.JudgeService;
import com.dduo.dduoj.model.dto.questionsubmit.QuestionSubmitAddRequest;
import com.dduo.dduoj.model.dto.questionsubmit.QuestionSubmitQueryRequest;
import com.dduo.dduoj.model.entity.Question;
import com.dduo.dduoj.model.entity.QuestionSubmit;
import com.dduo.dduoj.model.entity.User;
import com.dduo.dduoj.model.enums.QuestionSubmitLanguageEnum;
import com.dduo.dduoj.model.enums.QuestionSubmitStatusEnum;
import com.dduo.dduoj.mapper.QuestionSubmitMapper;
import com.dduo.dduoj.model.vo.QuestionSubmitVO;
import com.dduo.dduoj.service.QuestionService;
import com.dduo.dduoj.service.QuestionSubmitService;
import javax.annotation.Resource;import com.dduo.dduoj.service.UserService;
import com.dduo.dduoj.utils.SqlUtils;
import org.apache.commons.collections4.CollectionUtils;
import org.apache.commons.lang3.ObjectUtils;
import org.apache.commons.lang3.StringUtils;
import org.springframework.context.annotation.Lazy;
import org.springframework.stereotype.Service;import java.util.List;
import java.util.concurrent.CompletableFuture;
import java.util.stream.Collectors;/*** 提交题目服务实现**/
@Service
public class QuestionSubmitServiceImpl extends ServiceImpl<QuestionSubmitMapper, QuestionSubmit>implements QuestionSubmitService {@Resourceprivate QuestionService questionService;@Resourceprivate UserService userService;@Resource@Lazyprivate JudgeService judgeService;/*** 提交题目** @param questionSubmitAddRequest* @param loginUser* @return*/@Overridepublic long doQuestionSubmit(QuestionSubmitAddRequest questionSubmitAddRequest, User loginUser) {// 校验编程语言是否合法String language = questionSubmitAddRequest.getLanguage();QuestionSubmitLanguageEnum languageEnum = QuestionSubmitLanguageEnum.getEnumByValue(language);if (languageEnum == null) {throw new BusinessException(ErrorCode.PARAMS_ERROR, "编程语言错误");}long questionId = questionSubmitAddRequest.getQuestionId();// 判断实体是否存在,根据类别获取实体Question question = questionService.getById(questionId);if (question == null) {throw new BusinessException(ErrorCode.NOT_FOUND_ERROR);}// 是否已提交题目long userId = loginUser.getId();// 每个用户串行提交题目QuestionSubmit questionSubmit = new QuestionSubmit();questionSubmit.setUserId(userId);questionSubmit.setQuestionId(questionId);questionSubmit.setCode(questionSubmitAddRequest.getCode());questionSubmit.setLanguage(language);// 设置初始状态questionSubmit.setStatus(QuestionSubmitStatusEnum.WAITING.getValue());questionSubmit.setJudgeInfo("{}");boolean save = this.save(questionSubmit);if (!save){throw new BusinessException(ErrorCode.SYSTEM_ERROR, "数据插入失败");}Long questionSubmitId = questionSubmit.getId();// 执行判题服务CompletableFuture.runAsync(() -> {judgeService.doJudge(questionSubmitId);});return questionSubmitId;}/*** 获取查询包装类(用户根据哪些字段查询,根据前端传来的请求对象,得到 mybatis 框架支持的查询 QueryWrapper 类)** @param questionSubmitQueryRequest* @return*/@Overridepublic QueryWrapper<QuestionSubmit> getQueryWrapper(QuestionSubmitQueryRequest questionSubmitQueryRequest) {QueryWrapper<QuestionSubmit> queryWrapper = new QueryWrapper<>();if (questionSubmitQueryRequest == null) {return queryWrapper;}String language = questionSubmitQueryRequest.getLanguage();Integer status = questionSubmitQueryRequest.getStatus();Long questionId = questionSubmitQueryRequest.getQuestionId();Long userId = questionSubmitQueryRequest.getUserId();String sortField = questionSubmitQueryRequest.getSortField();String sortOrder = questionSubmitQueryRequest.getSortOrder();// 拼接查询条件queryWrapper.eq(StringUtils.isNotBlank(language), "language", language);queryWrapper.eq(ObjectUtils.isNotEmpty(userId), "userId", userId);queryWrapper.eq(ObjectUtils.isNotEmpty(questionId), "questionId", questionId);queryWrapper.eq(QuestionSubmitStatusEnum.getEnumByValue(status) != null, "status", status);queryWrapper.eq("isDelete", false);queryWrapper.orderBy(SqlUtils.validSortField(sortField), sortOrder.equals(CommonConstant.SORT_ORDER_ASC),sortField);return queryWrapper;}/** 单条数据* */@Overridepublic QuestionSubmitVO getQuestionSubmitVO(QuestionSubmit questionSubmit, User loginUser) {QuestionSubmitVO questionSubmitVO = QuestionSubmitVO.objToVo(questionSubmit);// 脱敏:仅本人和管理员能看见自己(提交 userId 和登录用户 id 不同)提交的代码long userId = loginUser.getId();// 处理脱敏if (userId != questionSubmit.getUserId() && !userService.isAdmin(loginUser)) {questionSubmitVO.setCode(null);}return questionSubmitVO;}/** 多条数据* */@Overridepublic Page<QuestionSubmitVO> getQuestionSubmitVOPage(Page<QuestionSubmit> questionSubmitPage, User loginUser) {List<QuestionSubmit> questionSubmitList = questionSubmitPage.getRecords();Page<QuestionSubmitVO> questionSubmitVOPage = new Page<>(questionSubmitPage.getCurrent(), questionSubmitPage.getSize(), questionSubmitPage.getTotal());if (CollectionUtils.isEmpty(questionSubmitList)) {return questionSubmitVOPage;}List<QuestionSubmitVO> questionSubmitVOList = questionSubmitList.stream().map(questionSubmit -> getQuestionSubmitVO(questionSubmit, loginUser)).collect(Collectors.toList());questionSubmitVOPage.setRecords(questionSubmitVOList);return questionSubmitVOPage;}}

controller层代码

/*** 提交题目** @param questionSubmitAddRequest* @param request* @return 提交记录的 id*/
@PostMapping("/")
public BaseResponse<Long> doQuestionSubmit(@RequestBody QuestionSubmitAddRequest questionSubmitAddRequest,HttpServletRequest request) {if (questionSubmitAddRequest == null || questionSubmitAddRequest.getQuestionId() <= 0) {throw new BusinessException(ErrorCode.PARAMS_ERROR);}// 登录才能点赞final User loginUser = userService.getLoginUser(request);long questionSubmitId = questionSubmitService.doQuestionSubmit(questionSubmitAddRequest, loginUser);return ResultUtils.success(questionSubmitId);
}

listQuestionSubmitByPage

/*** 分页获取题目提交(除了管理员外 普通用户是能看见非答案 提交代码等非公开信息)** @param questionSubmitQueryRequest* @return*/
@PostMapping("/list/page")
@AuthCheck(mustRole = UserConstant.ADMIN_ROLE)
public BaseResponse<Page<QuestionSubmitVO>> listQuestionSubmitByPage(@RequestBody QuestionSubmitQueryRequest questionSubmitQueryRequest, HttpServletRequest request) {long current = questionSubmitQueryRequest.getCurrent();long size = questionSubmitQueryRequest.getPageSize();//从数据库中获取信息Page<QuestionSubmit> questionSubmitPage = questionSubmitService.page(new Page<>(current, size),questionSubmitService.getQueryWrapper(questionSubmitQueryRequest));final User loginUser = userService.getLoginUser(request);//返回脱敏方法return ResultUtils.success(questionSubmitService.getQuestionSubmitVOPage(questionSubmitPage, loginUser));
}

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