电子病历中没有smtp的提供者

Question

我正试图在完成电子病历作业时发送一封电子邮件。我使用了libraryDependencies+="；com.sun.mail"%"javax.mail"%"1.6.2"；在我的sbt依赖关系中。

我在本地测试了电子邮件发送，它运行良好，但相同的工作在EMR工作中失败，以下例外：

20/11/21 04:28:12 WARN mail: expected resource not found: /META-INF/javamail.default.address.map
javax.mail.NoSuchProviderException: No provider for smtp
at javax.mail.Session.getProvider(Session.java:545)
at javax.mail.Session.getTransport(Session.java:744)
at javax.mail.Session.getTransport(Session.java:725)
at javax.mail.Session.getTransport(Session.java:782)
at javax.mail.Transport.send0(Transport.java:249)
at javax.mail.Transport.send(Transport.java:124)
at util.EmailUtil.sendEmail(EmailUtil.java:44)
at util.EmailUtil.sendMail(EmailUtil.java:59)
at com.here.places.rule.testing.EmailTester$.main(EmailTester.scala:16)
at com.here.places.rule.testing.EmailTester.main(EmailTester.scala)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:498)
at org.apache.spark.deploy.yarn.ApplicationMaster$$anon$4.run(ApplicationMaster.scala:706)

使用的代码是`公共类EmailUtil{public static void sendEmail(会话会话，字符串到电子邮件，字符串主题，字符串身体({尝试{MimeMessage msg=新MimeMessage(会话(；//设置邮件头msg.addHeader("内容类型"，"text/HTML；字符集=UTF-8"(；msg.addHeader("format"，"flow"(；msg.addHeader("内容传输编码"，"8bit"(；

msg.setFrom(new InternetAddress(toEmail));
msg.setReplyTo(InternetAddress.parse(toEmail));
msg.setSubject(subject, "UTF-8");
msg.setText(body, "UTF-8");
msg.setSentDate(new Date());
msg.setRecipients(Message.RecipientType.TO, InternetAddress.parse(toEmail, false));
System.out.println("Message is ready");
Transport.send(msg);
System.out.println("EMail Sent Successfully!!");
}
catch (Exception e) {
e.printStackTrace();
}
}
public static void sendMail() {
Properties props = System.getProperties();
props.put("mail.smtp.host", "***");
props.put("mail.smtp.port", "25");
Session session = Session.getInstance(props, null);
sendEmail(session, "***","SimpleEmail Testing Subject", "SimpleEmail Testing Body");
}

}`

Answer 1

应用程序使用SBT构建，并使用以下合并策略。

assemblyMergeStrategy in assembly := {
case PathList("META-INF", xs @ _*) => MergeStrategy.discard
case x => MergeStrategy.first
}

创建的fat jar没有来自javax.mail jar的必要META_INF文件，这导致了一个问题。出于测试目的，我手动将META-INF文件从javax.mail jar复制到fat jar，它就工作了。