File Attachment not working when attaching crm Content

Question

I have a page where the user selects content (that is 5MB or lower, only 2 attachments allowed per email) to use as an attachment in an email. It all seems to work fine, the email sends and there are attachments in it with the correct title. But the attachments themselves seems to be broken. There is nothing in them, or i get Forbidden Error 403 when i try to download them.

I have tried it will 3 types of content (power_point_x, power_point, pdf) and all fail like this. also when looking at the attachment in google drive, in the details section it says all three have a type of Mime type: application/octet-stream ? I know i am missing something simple here I am sure lol, just looking for some guidance.

Thanks!

  List<Messaging.EmailFileAttachment> attList = new List<Messaging.EmailFileAttachment>();
  Messaging.EmailFileAttachment efa;
  if (!selectedContent.isEmpty()) {
    for (ContentVersion cv : PromoModel_Helper.findSelected(selectedContent)) {
      if (cv != null) {
        efa = new Messaging.EmailFileAttachment();
        efa.setFileName(cv.Title);
        efa.setBody(cv.VersionData);
        attList.add(efa);
      }
    } 
  }

  mail = new Messaging.SingleEmailMessage();
  mail.setToAddresses(sendToIds);
  mail.setReplyTo(replyToEmail);
  mail.setSenderDisplayName(senderDisplayName);
  mail.setBccSender(bcc);
  mail.setUseSignature(signature);
  mail.setSubject(subject);
  mail.setHtmlBody(body);

  if (!attList.isEmpty()) {
    mail.setFileAttachments(attList);
  }

  try {
    List<Messaging.SendEmailResult> results = Messaging.sendEmail(
      new List<Messaging.Email> { mail }
    );
  } catch (Exception e) {
    ApexPages.addMessage(new ApexPages.Message(
      ApexPages.Severity.ERROR, 
      'An Error occured while trying to email, ' + e.getMessage()
    ));
    return null;
  }

Update: So i tried adding efa.setContentType(cv.FileType); which created an error saying the Messaging.SingleEmailMessage was Not Serializable, so I tried making it transient. That created an error around the file type:

An Error occured while trying to email, SendEmail failed. 
First exception on row 0; first error: INVALID_CONTENT_TYPE, An invalid value was specified for contentType.: []

The output of the cv.FileType is typically (PDF, POWER_POINT_X, POWER_POINT, WORD, EXCEL_X) and this seems to not work (given the error above, and yes i checked that it was getting the value i expected) So I tried converting it to file extensions

efa.setContentType(
  (cv.FileType == 'POWER_POINT_X' ? 
    '.pptx' : cv.FileType == 'POWER_POINT' ?
      '.ppt' : cv.FileType == 'PDF' ?
        '.pdf' : cv.FileType == 'EXCEL' ? 
          '.xls' : '.doc')
);

and still no joy :-(

Answer 1

As Daniel stated, you need to set the MIME Content-Type of the email attachment using the setContentType method. Unfortunately, ContentVersion.filetype is only returning the extension from (pdf, ppt, etc.), and the Content-Type is expecting the top-level media type as well. A registry of the top-level MIME Content-Types and their associated sub-types can be found at http://www.iana.org/assignments/media-types/media-types.xhtml, and one solution would be to get the extension, and then manually put the correct MIME Type (i.e. if ContentVersion.Filetype returns 'pdf', setContentType would need to recieve 'application/pdf')

Hopefully you don't have a lot of file types to deal with.

Instead of having a bunch of conditionals, it would also be possible to work this out through custom settings. Apache keeps a mime.types file that has a list of extensions with their associated MIME type here: http://svn.apache.org/repos/asf/httpd/httpd/trunk/docs/conf/mime.types. You could make a custom setting for the extensions and their related MIME Type, and then query the custom setting to retrieve the extensions MIME Type.

Answer 2

You will need to set the Mime Content-Type of the attachment to match that of the ContentVersion. This will tell your browser/mail client how to open the attachment.

The Mime Type for the ContentVersion is in FileType.

You can set the Mime Type on the EmailFileAttachment using setContentType().

efa = new Messaging.EmailFileAttachment();
efa.setFileName(cv.Title);

// Set the Attachment Mime Type to match that of the ContentVersion
efa.setContentType(cv.FileType);

efa.setBody(cv.VersionData);
attList.add(efa);

Also, it may not be strictly required, but you could also set the Content-Disposition to attachment for good measure.

efa.setInline(false);

---

So it appears the FileType doesn't directly map the the Mime Content-Type.

You will need to create a lookup structure to go from the stored value to the correct Mime type. Note that this isn't the same thing as a file extension.

Map<string, string> mimeTypeMap = new Map<string, string>();
mimeTypeMap.put('POWER_POINT_X', 'application/vnd.openxmlformats-officedocument.presentationml.presentation');
mimeTypeMap.put('POWER_POINT', 'application/vnd.ms-powerpoint');
mimeTypeMap.put('EXCEL', 'application/vnd.ms-excel');
// And so on...

// Should probably check here the the FileType is registered in the map.
efa.setContentType(mimeTypeMap.get(cv.FileType));