使用@nestjs/mailer 发送带有 Excel 附件的电子邮件

Question

我正在尝试通过@nestjs/mailer发送带有excel附件的电子邮件:

await this.mailService.send({ //service with @nestjs/mailer
      to: messageTo,
      subject: messageTitle,
      template: 'application-approved',
      context: {
        content: messageBody,
      },
      attachments: attachments.map(({ name, arrayBuffer }) => ({ // array with filenames and arrayBuffers
        filename: name, // filename like `name.xlsx`
        contents: arrayBuffer, // arrayBuffer contains filled excel file
        contentType: // tried to remove this property - no effect
          'application/vnd.openxmlformats-officedocument.spreadsheetml.sheet',
      })),
    });

当邮件到达时，所有附件都被标记为已损坏。我尝试同时发送 ArrayBuffer 和 Buffer - 它没有效果。

另一方面，创建文件并将其附加到响应的 HTTP 路由成功。

有解决这个问题的想法吗？

Answer 1

我从未使用过 @nestjs/mailer，但由于它在底层使用了 nodemailer，我会尝试这样做：

await this.mailService.send({
  to: messageTo,
  subject: messageTitle,
  template: 'application-approved',
  context: {
    content: messageBody,
  },
  attachments: attachments.map(({ name, arrayBuffer }) => ({
    filename: name,
    contents: Buffer.from(arrayBuffer).toString('base64'),
    contentTransferEncoding: 'base64',
    contentType: 'application/vnd.openxmlformats-officedocument.spreadsheetml.sheet',
  })),
});

如果这不起作用，也许您应该首先检查文件内容是否正确。可以把文件存盘打开，如果不行那就是数据问题，不是传输问题。

此外，检查 nodemailer 附件的类型定义，看看您还有哪些其他选项：

interface AttachmentLike {
  /** String, Buffer or a Stream contents for the attachmentent */
  content?: string | Buffer | Readable | undefined;
  /** path to a file or an URL (data uris are allowed as well) if you want to stream the file instead of including it (better for larger attachments) */
  path?: string | Url | undefined;
}

interface Attachment extends AttachmentLike {
  /** filename to be reported as the name of the attached file, use of unicode is allowed. If you do not want to use a filename, set this value as false, otherwise a filename is generated automatically */
  filename?: string | false | undefined;
  /** optional content id for using inline images in HTML message source. Using cid sets the default contentDisposition to 'inline' and moves the attachment into a multipart/related mime node, so use it only if you actually want to use this attachment as an embedded image */
  cid?: string | undefined;
  /** If set and content is string, then encodes the content to a Buffer using the specified encoding. Example values: base64, hex, binary etc. Useful if you want to use binary attachments in a JSON formatted e-mail object */
  encoding?: string | undefined;
  /** optional content type for the attachment, if not set will be derived from the filename property */
  contentType?: string | undefined;
  /** optional transfer encoding for the attachment, if not set it will be derived from the contentType property. Example values: quoted-printable, base64. If it is unset then base64 encoding is used for the attachment. If it is set to false then previous default applies (base64 for most, 7bit for text). */
  contentTransferEncoding?: '7bit' | 'base64' | 'quoted-printable' | false | undefined;
  /** optional content disposition type for the attachment, defaults to ‘attachment’ */
  contentDisposition?: 'attachment' | 'inline' | undefined;
  /** is an object of additional headers */
  headers?: Headers | undefined;
  /** an optional value that overrides entire node content in the mime message. If used then all other options set for this node are ignored. */
  raw?: string | Buffer | Readable | AttachmentLike | undefined;
}

使用@nestjs/mailer 发送带有 Excel 附件的电子邮件

Send email with Excel attachment using @nestjs/mailer

typescript

nodemailer

exceljs

nestjs