java - 为什么使用 Spring Mail 会丢失附件？ ( Kotlin )

Question

我想使用 Spring Boot 及其邮件库发送电子邮件。我是这样实现的:byteArray 不为 null 且不为空。

class Attachment(val fileName: String, val byteArray: ByteArray)
private val emailSender: JavaMailSender

[...]

private fun sendMessage(to: String, subject: String, text: String, attachments: List<Attachment>? = null) {
        val message = emailSender.createMimeMessage()
        val helper = MimeMessageHelper(message, true)
        message.setContent(text, "text/html; charset=utf-8")

        helper.setFrom(sender)
        helper.setTo(to)
        helper.setSubject(subject)

        // add attachment
        attachments?.forEach { attachment ->
            helper.addAttachment(attachment.fileName, ByteArrayResource(attachment.byteArray))
        }

        try {
            emailSender.send(message)
        } catch (e: MailException) {
            logger.warn("Email could not be sent: $to, reason: ${e.message}")
        }
}

Answer 1

如果您使用 Spring 的邮件帮助器类，那么您还需要在那里指定 html 内容。

private fun sendMessage(to: String, subject: String, text: String, attachments: List<Attachment>? = null) {
        val message = emailSender.createMimeMessage()
        val helper = MimeMessageHelper(message, true)

        helper.setFrom(sender)
        helper.setTo(to)
        helper.setSubject(subject)
        helper.setText(text, true)

        // add attachment
        attachments?.forEach { attachment ->
            helper.addAttachment(attachment.fileName, ByteArrayResource(attachment.byteArray))
        }

        try {
            emailSender.send(message)
        } catch (e: MailException) {
            logger.warn("Email could not be sent: $to, reason: ${e.message}")
        }
}