Unable to attach files to the email messages

Whenever I try to send email with attachment via EmailService, I receive following exception:

java.lang.IllegalStateException: Not in multipart mode - create an appropriate MimeMessageHelper via a constructor that takes a 'multipart' flag if you need to set alternative texts or add inline elements or attachments.
	at org.springframework.mail.javamail.MimeMessageHelper.checkMultipart(MimeMessageHelper.java:383)
	at org.springframework.mail.javamail.MimeMessageHelper.getRootMimeMultipart(MimeMessageHelper.java:400)
	at org.springframework.mail.javamail.MimeMessageHelper.addAttachment(MimeMessageHelper.java:998)
	at org.springframework.mail.javamail.MimeMessageHelper.addAttachment(MimeMessageHelper.java:1077)
	at it.ozimov.springboot.templating.mail.utils.EmailToMimeMessage.apply(EmailToMimeMessage.java:80)
	at it.ozimov.springboot.templating.mail.service.EmailServiceImpl.toMimeMessage(EmailServiceImpl.java:124)
	at it.ozimov.springboot.templating.mail.service.EmailServiceImpl.send(EmailServiceImpl.java:81)
...

I tried both plain text messages or created from Freemaker template, in both cases result is the same.

Code snippet:

@ActiveProfiles("service-test")
@RunWith(SpringJUnit4ClassRunner.class)
@SpringBootTest(classes = ServicesTestsConfiguration.class)
@TestPropertySource(locations = "classpath:application-test.properties")
public class MailTest {

    @Autowired
    public EmailService emailService;

    @Value("${mail.from}")
    private String emailFrom;

    @Value("${mail.to}")
    private String emailTo;

    private final Charset charset = Charset.forName("UTF-8");

    @Test
    public void testMail() throws AddressException, CannotSendEmailException {
        final String testData = "col1,col2\n1,2\n3,4";
        final EmailAttachmentImplBuilder attachment = EmailAttachmentImpl.builder().attachmentName("test.csv")
                .attachmentData(testData.getBytes(charset)).mediaType(MediaType.TEXT_PLAIN);
        final Email email = EmailImpl.builder().from(new InternetAddress(emailFrom)).to(Lists.newArrayList(new InternetAddress(emailTo)))
                .subject("subject").body("").encoding(charset).attachments(Lists.newArrayList(attachment.build())).build();

        final Map<String, Object> modelObject = Maps.newHashMap();
        modelObject.put("instance", "FooBar");

        // doesn't work neither: emailService.send(email);
        emailService.send(email, "email_test.ftl", modelObject);
    }

}

Thanks for looking into the issue, Maciej

[maciejlach]

@robertotru thanks! Plain text emails with attachments are now working fine.

With templated ones, original attachments are not present in the final message.

According to SO the email should have structure similar to this one:

multipart/mixed
    multipart/alternative
        text/plain
        multipart/related
            text/html
            image/jpeg
    application/pdf

It seems like method EmailServiceImpl#send(Email email, String template, Map<String, Object> modelObject, InlinePicture... inlinePictures) overwrites the original MimeMessage content and creates structure like:

multipart/related
    text/html
    image/jpeg

[maciejlach]

@robertotru thank you for looking into this.

Unfortunately, after upgrading to 0.3.6, I’m still having issue with attachments.

When using the freemarker template (emailService.send(email, "email_test.ftl", modelObject); in my code snippet), email is sent without any exceptions, but the attachment is missing when I view the email in my inbox:

Return-Path: <[e-mail]>
Received: from ----- ([-----])
        by smtp.gmail.com with ESMTPSA id h15sm4452941ljb.46.2017.01.08.22.37.24
        for <[e-mail]>
        (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128);
        Sun, 08 Jan 2017 22:37:24 -0800 (PST)
From: "[e-mail]" <[e-mail]>
X-Google-Original-From: "[e-mail]" <[e-mail]>
Date: Mon, 9 Jan 2017 07:37:13 +0100 (CET)
To: [e-mail]
Message-ID: <2133612542.3.1483943843982@lachoo-nb>
Subject: 65cb9087-08db-4a6b-b7ce-77446152fc4d
MIME-Version: 1.0
Content-Type: multipart/related; boundary="----=_Part_2_501530336.1483943833656"

------=_Part_2_501530336.1483943833656
Content-Type: text/html; charset=UTF-8
Content-Transfer-Encoding: 7bit

<!doctype html>
<html>
  <body>
    <p>Sent from: FooBar</p>
  </body>
</html>

------=_Part_2_501530336.1483943833656--

While using the library without templates: emailService.send(email);, I’m getting this exception:

org.springframework.mail.MailSendException: Failed messages: javax.mail.internet.ParseException: In Content-Type string <text>, expected '/', got null; message exception details (1) are:
Failed message 1:
javax.mail.internet.ParseException: In Content-Type string <text>, expected '/', got null
	at javax.mail.internet.ContentType.<init>(ContentType.java:104)
	at javax.mail.internet.MimeBodyPart.updateHeaders(MimeBodyPart.java:1467)
	at javax.mail.internet.MimeBodyPart.updateHeaders(MimeBodyPart.java:1131)
	at javax.mail.internet.MimeMultipart.updateHeaders(MimeMultipart.java:515)
	at javax.mail.internet.MimeBodyPart.updateHeaders(MimeBodyPart.java:1490)
	at javax.mail.internet.MimeMessage.updateHeaders(MimeMessage.java:2198)
	at javax.mail.internet.MimeMessage.saveChanges(MimeMessage.java:2159)
	at org.springframework.mail.javamail.JavaMailSenderImpl.doSend(JavaMailSenderImpl.java:443)
	at org.springframework.mail.javamail.JavaMailSenderImpl.send(JavaMailSenderImpl.java:345)
	at org.springframework.mail.javamail.JavaMailSenderImpl.send(JavaMailSenderImpl.java:340)
	at it.ozimov.springboot.templating.mail.service.EmailServiceImpl.send(EmailServiceImpl.java:72)