SpringBoot发送邮件

课程目录

1、第一部分 背景

• 使用场景
• 发送原理
• 发送历史
• SpringBoot介绍
• 前置知识

2、第二部分 实践

• 文本邮件
• HTML邮件
• 附件邮件
• 图片邮件
• 邮件模板
• 邮件系统

第一部分 背景

1、邮件使用场景

• 注册验证
• 网站营销
• 安全防线
• 提醒监控
• 触发机制

2、邮件发送原理

• SMPTP协议 发送协议
• POP3协议 接收协议
• IMAP协议 对POP3补充
• Mime协议

3、邮件发送历史

• 1969年10月世界第一封
• 1987年9月14日中国第一封

4、SpringBoot介绍

• 约定大于配置
• 简单快速开发
• 强大生态链

5、前置知识

• Spring
• Maven
• HTML
• Thymeleaf

第二部分 实践

1、学习路径

• 基础配置
• 文本邮件
• HTML邮件
• 附件邮件
• 图片邮件
• 邮件模板
• 异常处理
• 邮件系统

2、环境配置

初始化SpringBoot项目
https://start.spring.io/

版本：2.3.5.RELEASE

Service示例

package com.example.demo.service;import org.springframework.stereotype.Service;@Service
public class HelloService {public void sayHello(){System.out.println("Hello");}
}

测试类

package com.example.demo;import com.example.demo.service.HelloService;
import org.junit.jupiter.api.Test;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.test.context.SpringBootTest;@SpringBootTest
class DemoApplicationTests {@AutowiredHelloService helloService;@Testvoid sayHelloTest() {helloService.sayHello();}}

3、项目配置

• 引入jar包

<!-- 邮件 -->
<dependency><groupId>org.springframework.boot</groupId><artifactId>spring-boot-starter-mail</artifactId>
</dependency><!-- 模板引擎 -->
<dependency><groupId>org.springframework.boot</groupId><artifactId>spring-boot-starter-thymeleaf</artifactId>
</dependency>

• 配置邮箱参数

spring.mail.host=smtp.163.com
spring.mail.username=username@163.com
# 户端授权码
spring.mail.password=password
spring.mail.default-encoding=UTF-8

4、发送邮件

• 封装SimpleMailMessage
• JavaMailSender进行发送

package com.example.demo.service;import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.core.io.FileSystemResource;
import org.springframework.mail.SimpleMailMessage;
import org.springframework.mail.javamail.JavaMailSender;
import org.springframework.mail.javamail.MimeMessageHelper;
import org.springframework.stereotype.Service;import javax.mail.MessagingException;
import javax.mail.internet.MimeMessage;
import java.io.File;@Service
public class MailService {private final Logger logger = LoggerFactory.getLogger(this.getClass());@Value("${spring.mail.username}")private String fromUser;@Autowiredprivate JavaMailSender mailSender;/*** 文本邮件** @param toUser* @param subject* @param content*/public void sendSimpleMail(String toUser, String subject,String content) {SimpleMailMessage message = new SimpleMailMessage();message.setFrom(fromUser);message.setTo(toUser);message.setSubject(subject);message.setText(content);mailSender.send(message);}/*** html邮件** @param toUser* @param subject* @param content*/public void sendHtmlMail(String toUser, String subject,String content) {logger.info("html邮件开始：{} {} {}", toUser, subject, content);MimeMessage message = mailSender.createMimeMessage();MimeMessageHelper helper = null;try {helper = new MimeMessageHelper(message, true);helper.setFrom(fromUser);helper.setTo(toUser);helper.setSubject(subject);helper.setText(content, true);mailSender.send(message);logger.info("html邮件成功");} catch (MessagingException e) {e.printStackTrace();logger.error("html邮件失败：", e);}}/*** 附件邮件** @param toUser* @param subject* @param content* @param filePath 绝对路径* @throws MessagingException*/public void sendAttachmentsMail(String toUser, String subject,String content, String filePath)throws MessagingException {MimeMessage message = mailSender.createMimeMessage();MimeMessageHelper helper = new MimeMessageHelper(message, true);helper.setFrom(fromUser);helper.setTo(toUser);helper.setSubject(subject);helper.setText(content, true);FileSystemResource file = new FileSystemResource(new File(filePath));// 可以多次添加附件helper.addAttachment(file.getFilename(), file);mailSender.send(message);}/*** 图片邮件** @param toUser* @param subject* @param content* @param resourcePath* @param resourceId* @throws MessagingException*/public void sendInlineResourceMail(String toUser, String subject,String content, String resourcePath, String resourceId)throws MessagingException {MimeMessage message = mailSender.createMimeMessage();MimeMessageHelper helper = new MimeMessageHelper(message, true);helper.setFrom(fromUser);helper.setTo(toUser);helper.setSubject(subject);helper.setText(content, true);FileSystemResource resource = new FileSystemResource(new File(resourcePath));// 可以多次添加图片helper.addInline(resourceId, resource);mailSender.send(message);}
}

• 发送测试

package com.example.demo;import com.example.demo.service.MailService;
import org.junit.jupiter.api.Test;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.test.context.SpringBootTest;
import org.springframework.core.io.ClassPathResource;
import org.thymeleaf.TemplateEngine;
import org.thymeleaf.context.Context;import javax.mail.MessagingException;
import java.io.IOException;@SpringBootTest
class DemoApplicationTests {@AutowiredMailService mailService;@AutowiredTemplateEngine templateEngine;@Testvoid sendSimpleMailTest() {mailService.sendSimpleMail("pengshiyuyx@163.com","文本邮件标题","邮件内容");}@Testvoid sendHtmlMailTest() {String content = "<html>" +"<body>" +"<h3>这是邮件内容</h3>" +"</body>" +"</html>";mailService.sendHtmlMail("pengshiyuyx@163.com","HTML邮件标题",content);}@Testvoid sendAttachmentsMailTest() throws MessagingException, IOException {String filePath = "name.txt";ClassPathResource resource = new ClassPathResource(filePath);mailService.sendAttachmentsMail("pengshiyuyx@163.com","附件邮件标题","邮件内容",resource.getFile().getAbsolutePath());}@Testvoid sendInlineResourceMailTest() throws IOException, MessagingException {String imagePath = "demo.jpg";String resourceId = "image001";String content = "<html>" +"<body>" +"<h3>这是邮件内容</h3>" +"<img src='cid:" + resourceId + "'>" +"</body>" +"</html>";ClassPathResource resource = new ClassPathResource(imagePath);mailService.sendInlineResourceMail("pengshiyuyx@163.com","图片邮件标题",content,resource.getFile().getAbsolutePath(),resourceId);}@Testvoid sendTemplateMailTest() {Context content = new Context();content.setVariable("id", "007");String mailContent = templateEngine.process("mail", content);mailService.sendHtmlMail("pengshiyuyx@163.com","模板邮件标题",mailContent);}}

模板

<!DOCTYPE html>
<html lang="en" xmlns:th="https://www.thymeleaf.org/">
<head><meta charset="UTF-8"/><title>Title</title>
</head>
<body><p>感谢注册</p><p><a href="" th:href="@{https://www.baidu.com/{id}(id=${id})}">点击激活</a></p>
</body>
</html>

常见错误

• 421 HL:ICC 该IP同事并发连接数过大
• 451 Requested mail action not taken: too much fail
  登录失败次数过多，被临时禁止登录
• 553 authentication is required 认证失败

更多错误
http://help.163.com/09/1224/17/5RAJ4LMH00753VB8.html

邮件系统

• 独立微服务MQ
• 异常处理
• 定时重试邮件
• 异步发送

总结

• 邮件发送历史和原理
• SpringBoot 和邮件系统
• 各种类型邮件的发送
• 邮件系统