How to send attachment through Mailjet in JAVA

Question

I want to send mail with an attachment through Mailjet in java. I have no problem while sending simple mail without attachment but when I try to add attachment I am getting this error:

400
[{"ErrorIdentifier":"314408e7-e528-469f-9361-2eb3c24b2b32","ErrorCode":"mj-0004","ErrorRelatedTo":["Messages.Attachments"],"ErrorMessage":"Type mismatch. Expected type \"Attachments\".","StatusCode":400}]

And my code looks like this:

@Service
public class MailJetSenderImp implements MailJetSender {

    Message message = new Message();

    @Override
    public ResponseEntity<Message> sendMail(String To, String Body, String Subject, File attachment) throws MailjetSocketTimeoutException, JSONException, IOException {

        FileInputStream fileInputStream = new FileInputStream(attachment);
        int byteLength=(int) attachment.length(); //bytecount of the file-content
        byte[] filecontent = new byte[byteLength];
        fileInputStream.read(filecontent,0,byteLength);
        byte[] encoded = Base64.getEncoder().encode(filecontent);


        MailjetRequest email = new MailjetRequest(Emailv31.resource)

                .property(Emailv31.MESSAGES, new JSONArray()
                        .put(new JSONObject()
                                .put(Emailv31.Message.FROM, new JSONObject()
                                        .put("Email","xxxxxx@gmail.com" )
                                        .put("Name", "xxxxx"))
                                .put(Emailv31.Message.TO, new JSONArray()
                                        .put(new JSONObject()
                                                .put("Email", To)))
                                .put(Emailv31.Message.SUBJECT, Subject)
                                .put(Emailv31.Message.TEXTPART, "")
                                .put(Emailv31.Message.HTMLPART, Body)
                                    .put(Emailv31.Message.ATTACHMENTS,encoded)));

        final String mailjetApiKey = "xxxxxxxx";
        final String mailjetSecretKey = "yyyyyyyy";

        MailjetClient client = new MailjetClient(
                mailjetApiKey, mailjetSecretKey, new ClientOptions("v3.1"));


        try {
            // trigger the API call
            MailjetResponse response = client.post(email);
            // Read the response data and status
            System.out.println(response.getStatus());
            System.out.println(response.getData());
            message.setCode(response.getStatus());
            message.setMessage(response.getData().toString());
            return ResponseEntity.status(HttpStatus.OK).body(message);
        } catch (MailjetException e) {
            System.out.println("Mailjet Exception: " + e);
            message.setCode(400);
            message.setMessage("could not send email");
            return ResponseEntity.status(HttpStatus.BAD_REQUEST).body(message);

        }
    }
}

I get error message on (.put(Emailv31.Message.ATTACHMENTS,encoded)));

TechFree · Accepted Answer · 2019-12-30T06:32:28.163

Here is the Java code to send the mail attachment

The ATTACHMENTS data is a JSON array containing 3 fields:

ContentType - Content type of the attachment

Filename - name of the file attachment that the receiver would see

Base64Content - Base64 encoded file data as String

So, encode the file content as String ( I used the Base64 encoder from mailjet client JAR itself here ). filecontent is the byte[]. A hardcoded PDF file code sample below :

    java.nio.file.Path pdfPath = 
         java.nio.file.Paths.get("c:\\D\\sample.pdf");
    byte[] filecontent = java.nio.file.Files.readAllBytes(pdfPath);
    String fileData = com.mailjet.client.Base64.encode(filecontent);

Next, use this code to send the attachment, your other code remains same. Example here is for a PDF file, choose your MIME type correctly

  .put(Emailv31.Message.ATTACHMENTS,
            new JSONArray().put(new JSONObject().put("ContentType", "application/pdf")
                           .put("Filename", "abc.pdf")
                           .put("Base64Content", fileData)))
 .put(Emailv31.Message.HTMLPART,...

The code works for but while opening pdf after sending mail, it say file gets corrupted or unsupported (can not open file) — Avinaya Acharya, Dec 29 '19 at 13:59
Added some more code that would help you to test the functionality. The received file in gmail can be opened. Please check your other upstream code for the file corruption issue. — TechFree, Dec 30 '19 at 06:33

How to send attachment through Mailjet in JAVA

1 Answers1