# MailListen

**Repository Path**: dftdla/mail-listen

## Basic Information

- **Project Name**: MailListen
- **Description**: 监听邮箱未读文件，对满足条件的邮件处理转发给webhook地址
- **Primary Language**: Java
- **License**: MulanPSL-2.0
- **Default Branch**: master
- **Homepage**: None
- **GVP Project**: No

## Statistics

- **Stars**: 1
- **Forks**: 0
- **Created**: 2023-08-22
- **Last Updated**: 2024-11-19

## Categories & Tags

**Categories**: Uncategorized

**Tags**: mail, Java, webhook

## README

#  业务背景

​    当服务器的告警日志信息发送到邮箱时，我们无法及时查收，这可能导致问题扩大，需要一个全天候的服务监听邮箱的邮件

# 服务流程

​    定时执行邮件列表过滤流程，当检测到是未读的告警日志邮件时，将邮件富文本转为普通文本，经过post json方式推送至webhook地址（这里使用飞书机器人）

​    这样的做法可以保证日志信息的完整，并且在服务宕机时，还可以在重启时继续无损运行

## 邮件列表过滤

​    将符合条件的邮件（主题包含yml文件中配置的filterTitle字符串）的部件组合为一个String字符串，注意这里无法处理附件

```java
public void fetchMail() {

        if(OPEN){
            System.out.println("邮件转发已被关闭");
            return;
        }

        synchronized (OPEN){
            try {
                if(!(folder!=null&&folder.isOpen())){
                    openFolder();
                }
                int size = folder.getMessageCount();

                System.out.println("邮件个数：" + size);

                if(skip!=null&&skip&&messageLastSize!=null&&messageLastSize==size){
                    System.out.println("跳过未读邮件检测");
                }else{
                    messageLastSize = size;
                    for(int i = 0;i<size;i++){

                        Message message = folder.getMessage(size-i);
                        String subject = message.getSubject();

                        //判断主题包含WGCLOUD
                        if(!subject.contains(filterTitle)){
                            continue;
                        }

                        if(message.getFlags().contains(Flags.Flag.SEEN)){
                            continue;
                        }

                        System.out.println("未读邮件为:");

                        String from = message.getFrom()[0].toString();
                        Date date = message.getSentDate();
                        System.out.println("\tFrom: \t" + from.replaceAll("<.+?>",""));
                        System.out.println("\tSubject: \t" + subject);
                        System.out.println("\tDate: \t" + date);
                        MimeMultipart mimeMultipart = (MimeMultipart) message.getContent();

                        StringBuilder text = new StringBuilder();

                        // 遍历部件列表
                        for (int j = 0; j < mimeMultipart.getCount(); j++) {
                            BodyPart bodyPart = mimeMultipart.getBodyPart(j);

                            // 检查部件的内容类型
                            if (bodyPart.isMimeType("text/plain")) {
                                text.append((String) bodyPart.getContent());
                            } else if (bodyPart.isMimeType("text/html")) {
                                text.append((String) bodyPart.getContent());
                            }

                        }

                        System.out.println(sendFeiShuBot.sendMessageToBot(text.toString()));
                    }
                }

            } catch (Exception e) {
                e.printStackTrace();
            } finally {
                try {
                    if (folder != null) {
                        folder.close(false);
                    }
                    if (store != null) {
                        store.close();
                    }
                } catch (MessagingException e) {
                    e.printStackTrace();
                }
            }
            System.out.println("接收完毕！");
        }
    }
```

![点击并拖拽以移动](data:image/gif;base64,R0lGODlhAQABAPABAP///wAAACH5BAEKAAAALAAAAAABAAEAAAICRAEAOw==)

## 发送webhook

​    需要发送的文本经过正则过滤处理后，post给webHookUrl地址

​    regexStr在yml文件中配置

```java
public String sendMessageToBot(String text){

        System.out.println("接收到发送任务：" + text);
        text = text.replaceAll("[\\\\]", " ");
        text = text.replaceAll("[\b\r\n\t\"]", " ");
        text = text.replaceAll("<[^>]+>"," ");
        text = text.replaceAll(regexStr,"");
        System.out.println("处理后的文本：" + text);

        OkHttpClient client = new OkHttpClient().newBuilder()
                .build();

        MediaType mediaType = MediaType.parse("application/json");

        String json =
                "{\n" +
                "    \"msg_type\": \"text\",\n" +
                "    \"content\":{\n" +
                "        \"text\":\"" + text +"\"\n" +
                "    }\n" +
                "}";

        RequestBody body = RequestBody.create(mediaType, json);

        Request request = new Request.Builder()
                .url(HOST)
                .post(body)
                .build();

        try {
            System.out.println("已发送请求:" + json);
            Response response = client.newCall(request).execute();
            return Objects.requireNonNull(response.body()).string().contains("success") ?"success": Objects.requireNonNull(response.body()).string();
        } catch (IOException e) {
            e.printStackTrace();
            return null;
        }

    }
```

![点击并拖拽以移动](data:image/gif;base64,R0lGODlhAQABAPABAP///wAAACH5BAEKAAAALAAAAAABAAEAAAICRAEAOw==)

## 定时与接口

​    Appilcation的内容包含下面的接口和定时任务

​    需要更复杂处理的可以自己按照需求修改

```java
	@Bean
	public TaskScheduler scheduler() {
		ThreadPoolTaskScheduler taskScheduler = new ThreadPoolTaskScheduler();
		taskScheduler.setPoolSize(10);
		taskScheduler.setThreadNamePrefix("MailServer");
		return taskScheduler;
	}

	@Resource
	private ListenMail listenMail;

	@Scheduled(cron = "0/10 * * * * ? ")
	public void mailHandle(){
		listenMail.fetchMail();
	}

	@RequestMapping("/openListen")
	public String openMailListen(){
		return listenMail.startListen()?"邮件转发已开启":"邮件转发开启失败";
	}

	@RequestMapping("/closeListen")
	public String closeMailListen(){
		return listenMail.stopListen()?"邮件转发已关闭":"邮件转发关闭失败";
	}

	@RequestMapping("/statusListen")
	public String getMailStatus(){
		return !listenMail.getOpen()?"邮箱监听中":"邮箱静默中";
	}

	@RequestMapping("/mailConfig")
	public String configMail(){
		return listenMail.getConfig();
	}

	@RequestMapping("/checkPassword")
	public String checkPassword(String password){
		return listenMail.checkPassword(password)?"密码一致":"密码不一致";
	}

	@RequestMapping("/checkWebHook")
	public String checkWebHook(String url){
		return listenMail.checkWebHook(url)?"webhook地址一致":"webhook地址不一致";
	}
```

![点击并拖拽以移动](data:image/gif;base64,R0lGODlhAQABAPABAP///wAAACH5BAEKAAAALAAAAAABAAEAAAICRAEAOw==)

## yml 配置

​    服务运行在3333端口，下面host为你邮箱的接受邮件服务器地址

​    这里以qq邮箱的imap和飞书机器人为例

​    注意授权码需要在邮箱设置中开启，详细可以百度一下

​    skip参数用于判断是否在邮件数量不变时跳过检测，这一步可以在邮件数量大的情况下大大节省时间

​    filterTitle参数用于判断邮箱是否是所需邮件，它会用于与邮件的主题对比，如果包含则是

```javascript
server:
  port: 3333
spring:
  application:
    name: listenMailServer
listen:
  mail:
    host: imap.qq.com
    port: 993
    usermail: axinfree@qq.com
    password: xxxx #邮箱授权码，不是账号密码
    protocol: imap
    folder: INBOX #获取的邮箱文件夹，如未对邮箱做特别设置，默认INBOX即可
    filterTitle: "WGCLOUD" #邮件检索条件，包含这段字符串的未读邮箱才会被提取数据并发送
    skip: true #ture表示开启，当开启时，若检测到邮件数量没有变化，会跳过检测未读邮件的步骤
send:
  webHookUrl: https://open.feishu.cn/open-apis/bot/v2/hook/xxxx
  regexStr: "WGCLOUD 敬上" #发送webhook之前被替换摘除的文本 如： regexStr = “2” ‘123465’-> ’13465‘
```

![点击并拖拽以移动](data:image/gif;base64,R0lGODlhAQABAPABAP///wAAACH5BAEKAAAALAAAAAABAAEAAAICRAEAOw==)

# 效果图

![输入图片说明](deea9109e2ed45d3991866308b9f03fb.png)