MIME email multipart parser [duplicate]

Question

I'm looking for a node.js module that can parse my IMAP request - FETCH 1 BODY[TEXT]. I need multipart parser, because I have messages with few levels in hierarchy.

Example of message:

--94eb2c032ec81bf420053483f579
Content-Type: multipart/alternative; boundary=94eb2c032ec81bf411053483f577

--94eb2c032ec81bf411053483f577
Content-Type: text/plain; charset=UTF-8

test

--94eb2c032ec81bf411053483f577
Content-Type: text/html; charset=UTF-8

<div dir="ltr">test</div>

--94eb2c032ec81bf411053483f577--
--94eb2c032ec81bf420053483f579
Content-Type: image/x-icon; name="favicon.ico"
Content-Disposition: attachment; filename="favicon.ico"
Content-Transfer-Encoding: base64
X-Attachment-Id: f_ip2cdokt0

AAABAAEAEA8AAAEAIA... THIS IS ATTACHMENT ...A8AcAAPw/AAA=
--94eb2c032ec81bf420053483f579--)

Answer 1

With mailparser we can parse source of e-mail messages into a structured object. It's supports multipart levels - so html/text/attachments will stay in the object and we can find them in attributes.

For example:

const simpleParser = require('mailparser').simpleParser


var f = imap.fetch(results, { bodies: '' })

f.on('message', function (msg, seqno) {
  msg.on('body', async function (stream) {
    const parsed = await simpleParser(stream)

    if (parsed) {
      const fromEmail = parsed.from?.value?.[0]?.address

      if (fromEmail) {
        if (parsed.subject?.length > 0) {
          console.log('parsed.subject :>> ', parsed.subject)
        }

        const lines = parsed.text?.split('\n')
        lines.forEach(function (line, indx) {
          if (line?.length > 0) {
            console.log(`parsed.text[${indx}] :>> `, line)
          }
        })
      } else {
        console.warn('No from email found in', parsed)
      }
    }
  })

  msg.once('end', function () {
    console.log(prefix + 'Finished')
  })
})