Virtual-Judge

基础代码来自 https://github.com/zhblue/vjudge

本人初步工作：

• 整理了所有的jar依赖，转变为Maven项目
• 接入新的OJ
• 给出Docker部署方案，实现一键部署
• 给出核心模块源码的简要解析

部署

docker-compose部署

1. 安装docker

curl -fsSL https://get.docker.com | bash -s docker --mirror Aliyun

2. 安装docker-compose

curl -L "https://github.com/docker/compose/releases/download/1.24.1/docker-compose-$(uname -s)-$(uname -m)" -o /usr/local/bin/docker-compose

chmod +x /usr/local/bin/docker-compose

ln -s /usr/local/bin/docker-compose /usr/bin/docker-compose

docker-compose --version

3. 编写docker-compose.yml（见deploy目录）

version: "3"
services:
  voj-mysql:
    image: mysql:5.7
    container_name: voj-mysql
    command: mysqld --character-set-server=utf8mb4 --collation-server=utf8mb4_unicode_ci
    restart: always
    environment:
      - MYSQL_ROOT_PASSWORD=root #设置root帐号密码
      - TZ=Asia/Shanghai
    ports:
      - 3306:3306
    volumes:
      - /mydata/vjudge/mysql/data/db:/var/lib/mysql #数据文件挂载
      - /mydata/vjudge/mysql/data/conf:/etc/mysql/conf.d #配置文件挂载
      - /mydata/vjudge/mysql/log:/var/log/mysql #日志文件挂载

  voj-tomcat:
    image: tomcat:9.0
    container_name: voj-tomcat
    restart: always
    depends_on:
      - voj-mysql
    volumes:
      - /mydata/vjudge/tomcat/logs:/usr/local/tomcat/logs
      - /mydata/vjudge/tomcat/webapps:/usr/local/tomcat/webapps
      - /mydata/vjudge/data:/data
    environment:
      - TZ=Asia/Shanghai
    ports:
      - 80:8080

4. 启动

docker-compose up -d

5. 将vjudge.war放至/mydata/vjudge/tomcat/webapps目录
6. 修改log4j.properties

sed -i 's#../logs/log4j.log#/usr/local/tomcat/logs/log4j.log#g' /mydata/vjudge/tomcat/webapps/vjudge/WEB-INF/classes/log4j.properties

7. 将数据库SQL脚本导入MySQL（见deploy目录）

8. 远程账户可在/mydata/vjudge/tomcat/webapps/vjudge/WEB-INF/classes/remote_accounts.json配置

9. 重启voj-tomcat容器

   docker restart voj-tomcat

   访问ip/vjudge测试

10. 配置vjudge项目可通过根路径访问

• docker cp voj-tomcat:/usr/local/tomcat/conf/server.xml ./

• vi server.xml作出如下修改

<Host name="localhost"  appBase=""
    unpackWARs="true" autoDeploy="true">
	<Context docBase="webapps/vjudge" path="" /> 
</Host>

• docker cp ./server.xml voj-tomcat:/usr/local/tomcat/conf/

• 重启voj-tomcat容器

• 访问ip测试

https://stackoverflow.com/questions/4044129/tomcat-making-a-project-folder-the-web-root

https://segmentfault.com/a/1190000002985203

docker部署

docker run -p 3306:3306 --name mysql \
-v /mydata/mysql/log:/var/log/mysql \
-v /mydata/mysql/data:/var/lib/mysql \
-v /mydata/mysql/conf:/etc/mysql \
-e MYSQL_ROOT_PASSWORD=root  \
-d mysql:5.7

docker run -p 8080:8080 --name tomcat \
--link mysql:db \
-v /mydata/tomcat/webapps:/usr/local/tomcat/webapps \
-v /mydata/tomcat/logs:/usr/local/tomcat/logs \
-e TZ="Asia/Shanghai" \
-d tomcat:8.0.20

导入数据

修改config.properties的

• jdbc.url=jdbc:mysql://db/vhoj

访问ip:8080/vjudge

源码解析

judge.executor.TaskExecutor定义了线程池

两个方法：submitNoDelay和submitDelay（使用ScheduledExecutorService实现）

↓

judge.executor.Task定义任务

重要方法submit

被以下几个地方调用

• judge.remote.ProblemInfoUpdateManager#updateProblem 爬取
• judge.remote.SubmitCodeManager#submitCode 提交
• judge.remote.QueryStatusManager#createQuery 轮询
• judge.remote.account.RemoteAccountRepository#execute

loginer

judge.remote.loginer.RetentiveLoginer#login

crawler

业务

添加比赛功能：

contest_edit.js#updateTitle

addContest.jsp

judge.service.JudgeService#findProblemSimple

judge.remote.ProblemInfoUpdateManager#updateProblem

judge.remote.ProblemInfoUpdateTask具体实现Callable接口

核心代码 judge.remote.ProblemInfoUpdateTask#call

call方法中调用crawler.crawl(problemId, handler)执行爬题

judge.remote.crawler.SyncCrawler#crawl(problemId, handler)

info = judge.remote.crawler.SimpleCrawler#crawl(problemId)

judge.remote.provider.hdu.HDUCrawler#populateProblemInfo(info, problemId, html)

执行handler

crawler

CrawlersHolder维护一个HashMap

private static HashMap<RemoteOj, Crawler> crawlers = new HashMap<>();

SyncCrawler#crawl(problemId, handler)
	调用子类的crawl(problemId)
		调用子类的populateProblemInfo
	执行handler

submitter

RunningSubmissions
// submission.id -> submission
private Map<Integer, Submission> records = new ConcurrentHashMap<>();

业务

judge.action.ProblemAction#submit

judge.remote.SubmitCodeManager#submitCode进行判题

​ submission缓存到judge.remote.RunningSubmissions

​ new SubmitCodeTask(submission).submit();提交线程池执行

​ 核心代码 judge.remote.SubmitCodeManager.SubmitCodeTask#call

​ judge.remote.submitter.SubmittersHolder#getSubmitter根据OJ获取submitter实例

​ 调用judge.remote.submitter.SimpleSubmitter#submitCode(SubmissionInfo, Handler)

​ new SubmitTask(info, handler).submit();调用RemoteAccountTask的submit交由RemoteAccountTaskExecutor执行

​ RemoteAccountTaskExecutor的守护线程调用RemoteAccountRepository#handle(task)

​ RemoteAccountRepository#tryExecute(task)

​ findAccount

​ execute(task, account) Task实现Callable接口 并调用submit方法 交由TaskExecutor线程池去执行

​ 执行task.call 实际 judge.remote.submitter.SimpleSubmitter.SubmitTask#call

​ 需要登录则登录 获取HttpClient

​ SimpleSubmitter#submitCode(info, remoteAccount, client)完成远程提交 实际由子类(如MXTSubmitter)实现

​ SimpleSubmitter#getMaxRunId完成最新runID的获取

​ 结果放入RemoteAccountTask#resultQueue 任务执行完毕 再次入队

​ 调用Handler【将结果(SubmissionReceipt)作为参数】

​ submission.setRealRunId(receipt.remoteRunId);

​ queryStatusManager.createQuery(submission);开始查询

querier

每次提交时 将submissionId->Submission缓存于judge.remote.RunningSubmissions#records

private Map<Integer, Submission> records = new ConcurrentHashMap<>();

业务

提交后进行轮询judge.service.JudgeService#getResult

查询judge.remote.RunningSubmissions

judge.remote.QueryStatusManager#createQuery

​ runningSubmissions.add(submission); ​ new QueryStatusTask(submission, 0).submit();提交线程池执行

​ 核心代码judge.remote.QueryStatusManager.QueryStatusTask#call

​ QueriersHolder.getQuerier(info.remoteOj);获取Querier

​ judge.remote.querier.SyncQuerier#query(info, handler)

​ 具体query由子类具体实现 返回SubmissionRemoteStatus

​ 执行handler回调

​ int nextQueryDelaySeconds = submission.getQueryCount() + 2;

​ new QueryStatusTask(submission, nextQueryDelaySeconds).submit();

account

RemoteAccountTaskExecutorFactory创建RemoteAccountTaskExecutor

RemoteAccountTaskExecutor的构造函数中，根据远程账户配置构造RemoteAccountRepository

private Map<RemoteOj, RemoteAccountRepository> repos = new HashMap<>();

public RemoteAccountTaskExecutor(Map<RemoteOj, RemoteAccountOJConfig> config) {
    for (RemoteOj remoteOj : config.keySet()) {
        RemoteAccountOJConfig ojConfig = config.get(remoteOj);
        repos.put(remoteOj, new RemoteAccountRepository(remoteOj, ojConfig, this));
    }
}

RemoteAccountRepository

private final Map<String, RemoteAccountStatus> publicRepo = new HashMap<>();
private final Map<String, RemoteAccountStatus> privateRepo = new HashMap<>();

public RemoteAccountRepository(RemoteOj remoteOj, RemoteAccountOJConfig ojConfig, RemoteAccountTaskExecutor remoteAuthTaskExecutor) {
    this.remoteOj = remoteOj;
    this.remoteAuthTaskExecutor = remoteAuthTaskExecutor;
    // 初始化publicRepo和privateRepo
    for (RemoteAccountConfig accountConfig : ojConfig.accounts) {
        RemoteAccountStatus status = new RemoteAccountStatus(
                remoteOj,
                accountConfig.id,
                accountConfig.password,
                accountConfig.isPublic,
                ojConfig.contextNumber);
        (accountConfig.isPublic ? publicRepo : privateRepo).put(accountConfig.id, status);
    }
}

RemoteAccountRepository解析

execute

实现Callable接口 并调用submit方法 交由TaskExecutor去执行

tryBacklog

handle

被RemoteAccountTaskExecutor#init所调用

public void handle(RemoteAccountTask<?> task) {
    if (task.isDone()) {
        releaseAccount(task.getAccount());
    } else {
        tryExecute(task);
    }
}

tryExecute

​ findAccount获取未锁定的账号

​ execute(task, account);

releaseAccount

RemoteAccountTask

RemoteAccountTask#call方法交由子类去实现

被RemoteAccountRepository#execute调用

submit方法

public void submit() {
    if (!_submitted) {
        _submitted = true;
        SpringBean.getBean(RemoteAccountTaskExecutor.class).submit(this);
    }
}

调用RemoteAccountTaskExecutor#submit

核心RemoteAccountTaskExecutor

private LinkedBlockingQueue<RemoteAccountTask<?>> running = new LinkedBlockingQueue<>();

一个RemoteAccountTask两次进入该队列

• Apply for an account and execute 一次执行
• Return the account, whatever that task finishes normally 一次释放

submit

public void submit(RemoteAccountTask<?> task) {
    running.offer(task);//将任务放入队列
}

核心 RemoteAccountTaskExecutor#init

通过在配置文件中通过init-method指定该方法来初始化remoteAccountTaskExecutor

language

获取语言列表

judge.remote.language.LanguageManager#getLanguages(remoteOj, remoteProblemId)

自动登录

使用redis实现了自动登录功能