SpringBoot整合Mail

前言

SpringBoot实现邮件功能是非常的方便快捷的，因为SpringBoot默认有starter实现了Mail。
发送邮件应该是网站的必备功能之一，什么注册验证，忘记密码或者是给用户发送营销信息。
最早期的时候我们会使用JavaMail相关api来写发送邮件的相关代码，后来spring退出了
JavaMailSender更加简化了邮件发送的过程，在之后springboot对此进行了封装就有了
现在的spring-boot-starter-mail。

一、基础配置

1.1 引入依赖

<dependency><groupId>org.springframework.boot</groupId><artifactId>spring-boot-starter-mail</artifactId>
</dependency>
<dependency><groupId>org.springframework.boot</groupId><artifactId>spring-boot-starter-freemarker</artifactId>
</dependency>

1.2 获取QQ邮箱授权码

QQ邮箱->设置->账户->POP3/SMTP服务:开启服务后会获得QQ的授权码.

1.3 Mail配置文件

1）qq邮箱的配置

# JavaMailSender 邮件发送的配置
spring.mail.host=smtp.qq.com
spring.mail.username=用户qq邮箱
#QQ邮箱的授权码
spring.mail.password=授权码
spring.mail.properties.mail.smtp.auth=true
spring.mail.properties.mail.smtp.starttls.enable=true
spring.mail.properties.mail.smtp.starttls.required=true
spring.mail.default-encoding=UTF-8

2）163邮箱配置

spring.mail.host=smtp.163.com
spring.mail.username=用户163邮箱
spring.mail.password=邮箱密码
spring.mail.properties.mail.smtp.auth=true
spring.mail.properties.mail.smtp.starttls.enable=true
spring.mail.properties.mail.smtp.starttls.required=true
spring.mail.default-encoding=UTF-8

二、实现过程

2.1 配置文件

spring:#邮箱配置mail:host: smtp.qq.comusername: 917484312@qq.com#QQ邮箱的授权码password: 自己申请default-encoding: UTF-8properties:mail:smtp:auth: truestarttls:enable: truerequired: truefreemarker:content-type: text/html#后缀名suffix: .ftltemplate-loader-path: classpath:/templatescharset: UTF-8check-template-location: true#freemarker配置#设置一个邮件发送人
lance:mail:sender: 917484312@qq.com

2.2 实体Bean

/*** @author lance(ZYH)* @function  发送邮件-封装接受者信息* @date 2018-07-07 13:11*/
@Data
public class MailBean implements Serializable {private String recipient;   //邮件接收人private String subject; //邮件主题private String content; //邮件内容}

2.3 发送一个简单格式的邮件

    public void sendSimpleMail(MailBean mailBean) {try {SimpleMailMessage simpleMailMessage = new SimpleMailMessage();//邮件发送人simpleMailMessage.setFrom(MAIL_SENDER);//邮件接收人simpleMailMessage.setTo(mailBean.getRecipient());//邮件主题simpleMailMessage.setSubject(mailBean.getSubject());//邮件内容simpleMailMessage.setText(mailBean.getContent());javaMailSender.send(simpleMailMessage);} catch (Exception e) {logger.error("邮件发送失败", e.getMessage());}}

2.4 发送一个HTML格式的邮件

    public void sendHTMLMail(MailBean mailBean) {MimeMessage mimeMailMessage = null;try {mimeMailMessage = javaMailSender.createMimeMessage();MimeMessageHelper mimeMessageHelper = new MimeMessageHelper(mimeMailMessage, true);mimeMessageHelper.setFrom(MAIL_SENDER);mimeMessageHelper.setTo(mailBean.getRecipient());mimeMessageHelper.setSubject(mailBean.getSubject());StringBuilder sb = new StringBuilder();sb.append("<h1>SpirngBoot测试邮件HTML</h1>").append("\"<p style='color:#F00'>你是真的太棒了！</p>").append("<p style='text-align:right'>右对齐</p>");mimeMessageHelper.setText(sb.toString(), true);javaMailSender.send(mimeMailMessage);} catch (Exception e) {logger.error("邮件发送失败", e.getMessage());}}

2.5 发送带附件格式的邮件

    public void sendAttachmentMail(MailBean mailBean) {MimeMessage mimeMailMessage = null;try {mimeMailMessage = javaMailSender.createMimeMessage();MimeMessageHelper mimeMessageHelper = new MimeMessageHelper(mimeMailMessage, true);mimeMessageHelper.setFrom(MAIL_SENDER);mimeMessageHelper.setTo(mailBean.getRecipient());mimeMessageHelper.setSubject(mailBean.getSubject());mimeMessageHelper.setText(mailBean.getContent());//文件路径FileSystemResource file = new FileSystemResource(new File("src/main/resources/static/image/mail.png"));mimeMessageHelper.addAttachment("mail.png", file);javaMailSender.send(mimeMailMessage);} catch (Exception e) {logger.error("邮件发送失败", e.getMessage());}}

效果：

2.6 发送带静态资源的邮件

    public void sendInlineMail(MailBean mailBean) {MimeMessage mimeMailMessage = null;try {mimeMailMessage = javaMailSender.createMimeMessage();MimeMessageHelper mimeMessageHelper = new MimeMessageHelper(mimeMailMessage, true);mimeMessageHelper.setFrom(MAIL_SENDER);mimeMessageHelper.setTo(mailBean.getRecipient());mimeMessageHelper.setSubject(mailBean.getSubject());mimeMessageHelper.setText("<html><body>带静态资源的邮件内容，这个一张IDEA配置的照片:<img src='cid:picture' /></body></html>", true);//文件路径FileSystemResource file = new FileSystemResource(new File("src/main/resources/static/image/mail.png"));mimeMessageHelper.addInline("picture", file);javaMailSender.send(mimeMailMessage);} catch (Exception e) {logger.error("邮件发送失败", e.getMessage());}}

2.7 发送基于Freemarker模板的邮件

    public void sendTemplateMail(MailBean mailBean) {MimeMessage mimeMailMessage = null;try {mimeMailMessage = javaMailSender.createMimeMessage();MimeMessageHelper mimeMessageHelper = new MimeMessageHelper(mimeMailMessage, true);mimeMessageHelper.setFrom(MAIL_SENDER);mimeMessageHelper.setTo(mailBean.getRecipient());mimeMessageHelper.setSubject(mailBean.getSubject());Map<String, Object> model = new HashMap<String, Object>();model.put("content", mailBean.getContent());model.put("title", "标题Mail中使用了FreeMarker");Template template = configuration.getTemplate("mail.ftl");String text = FreeMarkerTemplateUtils.processTemplateIntoString(template, model);mimeMessageHelper.setText(text, true);javaMailSender.send(mimeMailMessage);} catch (Exception e) {logger.error("邮件发送失败", e.getMessage());}}

效果：

2.8 发送基于 thymeleaf为模板的邮件

1）pom中导入thymeleaf的包

<dependency><groupId>org.springframework.boot</groupId><artifactId>spring-boot-starter-thymeleaf</artifactId>
</dependency>

2）在resorces/templates下创建emailTemplate.html

<!DOCTYPE html>
<html lang="zh" xmlns:th="http://www.thymeleaf.org"><head><meta charset="UTF-8"/><title>Title</title></head><body>您好,这是验证邮件,请点击下面的链接完成验证,<br/><a href="#" th:href="@{ http://www.ityouknow.com/neo/{id}(id=${id}) }">激活账号</a></body>
</html>

3）解析模板并发送

@Test
public void sendTemplateMail() {//创建邮件正文Context context = new Context();context.setVariable("id", "006");String emailContent = templateEngine.process("emailTemplate", context);mailService.sendHtmlMail("ityouknow@126.com","主题：这是模板邮件",emailContent);
}

三、邮件服务的问题

3.1 邮件发送失败

因为各种原因，总会有邮件发送失败的情况，比如：邮件发送过于频繁、网络异常等。在出现这种情况的时候，
我们一般会考虑重新重试发送邮件，会分为以下几个步骤来实现：

接收到发送邮件请求，首先记录请求并且入库。
调用邮件发送接口发送邮件，并且将发送结果记录入库。
启动定时系统扫描时间段内，未发送成功并且重试次数小于3次的邮件，进行再次发送。

3.2 邮件异步发送

很多时候邮件发送并不是我们主业务必须关注的结果，比如通知类、提醒类的业务可以允许延时或者失败。
这个时候可以采用异步的方式来发送邮件，加快主交易执行速度，在实际项目中可以采用MQ发送邮件相关
参数，监听到消息队列之后启动发送邮件。

四、项目代码地址

https://github.com/LanceToBigData/SpringBootLearning/tree/develop/SpringBoot-Mail
个人觉得不错的邮件项目：
https://gitee.com/52itstyle/spring-boot-mail?spm=a2c4e.11153940.blogcont136451.12.523260361fBGiL