Extract info and attachments from a raw .eml Email file

email_info.py

# Based on https://stackoverflow.com/a/31392574/14711510

from pathlib import Path
import email
import email.utils as email_utils
import json

class EmailInfo:
    def __init__(self, email_file: str) -> None:
        email_file_path = Path(email_file)
        self.__email_files_dir = email_file_path.parent / 'attachments'
        if not self.__email_files_dir.exists():
            self.__email_files_dir.mkdir()

        with open(email_file_path, 'r') as email_file:
            email_message = email.message_from_file(email_file)

        _, self.from_address = email_utils.parseaddr(email_message['from'])
        _, self.to_address = email_utils.parseaddr(email_message['to'])
        self.subject = email_message['subject'].strip()
        self.date = email_utils.parsedate_to_datetime(email_message['date'])
        self.text, self.html, self.files = self.__extract(email_message)

    def __extract (self, message) -> tuple:
        '''Extracts content from an e-mail message. This works for multipart and nested multipart messages too.
        message -- email.Message() or mailbox.Message()
        Returns tuple(text, html, files)
        text    -- All text from all parts.
        html    -- All HTMLs from all parts.
        files   -- Dictionary mapping extracted attachment files.
        '''
        text = ''
        html = ''
        files = {}
        if not message.is_multipart():
            if message.get_filename(): # It's an attachment
                file_name = message.get_filename()
                files[file_name] = self.__email_files_dir / file_name
                if files[file_name].exists():
                    return text, html, files
                files[file_name].write_bytes(message.get_payload(decode = True))
                return text, html, files
            # Not an attachment!
            # See where this belongs. Text, Html or some other data:
            content_type = message.get_content_type()
            if content_type == 'text/plain':
                text += message.get_payload(decode = True).decode('utf-8') 
            elif content_type == 'text/html':
                html += message.get_payload(decode = True).decode('utf-8') 

            return text, html, files
        # This IS a multipart message.
        # So, we iterate over it and call __extract() recursively for each part.
        y = 0
        while 1:
            # If we cannot get the payload, it means we hit the end:
            try:
                payload = message.get_payload(y)
            except:
                break
            # payload is a new Message object which goes back to __extract
            t, h, f = self.__extract(payload)
            text += t
            html += h
            files.update(f)
            y += 1
        return text, html, files

    def __repr__(self) -> str:
        return json.dumps({
            'subject': self.subject,
            'from': self.from_address,
            'to': self.to_address,
            'date': self.date,
            'text': self.text,
            'html': self.html,
            'files': self.files,
        }, indent=4, sort_keys=True, default=str)