parser.py 文件源码

def get_subject_from_headers(headers):
    """
        Get the subject of an email

        :param `Message` headers: The SMTP headers of the email
        :rtype: str
        :return: The subject of the email
    """
    subject = ''
    subject_part = []
    if 'Subject' in headers and headers['Subject'] is not None:
        try:
            decodefrag = decode_header(headers['Subject'])
        except HeaderParseError:
            return subject

        for line, encoding in decodefrag:
            enc = 'utf-8' if encoding is None or encoding == 'unknown' else encoding
            subject_part.append(utils.decode_every_charset_in_the_world(line, enc))

        subject = ''.join(subject_part)[:1023]
    return subject