Question

I’m sending multipart mails with attachment from my grails application using the mail plugin.

On my local machine (Mac OS X) all works fine. If I deploy my app to tomcat6 (Ubuntu – ) the mail could not be sent due to an IllegalStateException:

Stacktrace follows: 
   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 grails.plugin.mail.MailMessageBuilder.doAdd(MailMessageBuilder.groovy:347) 
      at grails.plugin.mail.MailMessageBuilder.attach(MailMessageBuilder.groovy:308) 
      at grails.plugin.mail.MailMessageBuilder.attach(MailMessageBuilder.groovy:284) 
      at grails.plugin.mail.MailMessageBuilder.attachBytes(MailMessageBuilder.groovy:280)
      ...

Simple mails (not multipart) could be sent from tomat6 successfully.

Here is my code for sending multipart mails:

mailService.sendMail {
   multipart true
   to mail
   subject mySubject
   body (view: myView, model: myModel)
   attachBytes "${myTitle}.pdf", CH.config.grails.mime.types['pdf'], myBytes
} 

What can I do to avoid these Exception?

Where is the underlying JavaMail lib located? Is it packed into war file?

How can I find out which version of JavaMail is used within my tomcat6 and on my local machine?

Answer 1

I found the source of the problem – it was a stupid mistake of my own.

The call of the mailService was encapsulated into another service to add a default bcc in the following way:

def sendWithBcc(Closure callable) {
    // build a wrapper closure around the standard mail closure, which adds BCC functionality
    def newMailClosure = {
        if(CH.config.extraMail.bcc) {
            bcc(CH.config.extraMail.bcc)
        }

        // set the delegate of the inner closure to the delegate of this closure and call the inner closure
        callable.delegate = delegate
        callable.resolveStrategy = Closure.DELEGATE_FIRST
        callable.call()
    }

    return mailService.sendMail(newMailClosure)
}

On my local machine all works fine because I havn’t specified extraMail.bcc.

Just in the moment when the bcc is set, the multipart property of the outer closure seems to be ignored within the MailMessageBuilder.

The solution was to change the position of the bcc as shown below:

def sendWithBcc(Closure callable) {
    // build a wrapper closure around the standard mail closure, which adds BCC functionality
    def newMailClosure = {            
        // set the delegate of the inner closure to the delegate of this closure and call the inner closure
        callable.delegate = delegate
        callable.resolveStrategy = Closure.DELEGATE_FIRST
        callable.call()

        if(CH.config.extraMail.bcc) {
            bcc(CH.config.extraMail.bcc)
        }
    }

    return mailService.sendMail(newMailClosure)
}

Shame on me – next time I will post more precise code.