| import binascii |
| import email.charset |
| import email.message |
| import email.errors |
| from email import quoprimime |
| |
| class ContentManager: |
| |
| def __init__(self): |
| self.get_handlers = {} |
| self.set_handlers = {} |
| |
| def add_get_handler(self, key, handler): |
| self.get_handlers[key] = handler |
| |
| def get_content(self, msg, *args, **kw): |
| content_type = msg.get_content_type() |
| if content_type in self.get_handlers: |
| return self.get_handlers[content_type](msg, *args, **kw) |
| maintype = msg.get_content_maintype() |
| if maintype in self.get_handlers: |
| return self.get_handlers[maintype](msg, *args, **kw) |
| if '' in self.get_handlers: |
| return self.get_handlers[''](msg, *args, **kw) |
| raise KeyError(content_type) |
| |
| def add_set_handler(self, typekey, handler): |
| self.set_handlers[typekey] = handler |
| |
| def set_content(self, msg, obj, *args, **kw): |
| if msg.get_content_maintype() == 'multipart': |
| # XXX: is this error a good idea or not? We can remove it later, |
| # but we can't add it later, so do it for now. |
| raise TypeError("set_content not valid on multipart") |
| handler = self._find_set_handler(msg, obj) |
| msg.clear_content() |
| handler(msg, obj, *args, **kw) |
| |
| def _find_set_handler(self, msg, obj): |
| full_path_for_error = None |
| for typ in type(obj).__mro__: |
| if typ in self.set_handlers: |
| return self.set_handlers[typ] |
| qname = typ.__qualname__ |
| modname = getattr(typ, '__module__', '') |
| full_path = '.'.join((modname, qname)) if modname else qname |
| if full_path_for_error is None: |
| full_path_for_error = full_path |
| if full_path in self.set_handlers: |
| return self.set_handlers[full_path] |
| if qname in self.set_handlers: |
| return self.set_handlers[qname] |
| name = typ.__name__ |
| if name in self.set_handlers: |
| return self.set_handlers[name] |
| if None in self.set_handlers: |
| return self.set_handlers[None] |
| raise KeyError(full_path_for_error) |
| |
| |
| raw_data_manager = ContentManager() |
| |
| |
| def get_text_content(msg, errors='replace'): |
| content = msg.get_payload(decode=True) |
| charset = msg.get_param('charset', 'ASCII') |
| return content.decode(charset, errors=errors) |
| raw_data_manager.add_get_handler('text', get_text_content) |
| |
| |
| def get_non_text_content(msg): |
| return msg.get_payload(decode=True) |
| for maintype in 'audio image video application'.split(): |
| raw_data_manager.add_get_handler(maintype, get_non_text_content) |
| |
| |
| def get_message_content(msg): |
| return msg.get_payload(0) |
| for subtype in 'rfc822 external-body'.split(): |
| raw_data_manager.add_get_handler('message/'+subtype, get_message_content) |
| |
| |
| def get_and_fixup_unknown_message_content(msg): |
| # If we don't understand a message subtype, we are supposed to treat it as |
| # if it were application/octet-stream, per |
| # tools.ietf.org/html/rfc2046#section-5.2.4. Feedparser doesn't do that, |
| # so do our best to fix things up. Note that it is *not* appropriate to |
| # model message/partial content as Message objects, so they are handled |
| # here as well. (How to reassemble them is out of scope for this comment :) |
| return bytes(msg.get_payload(0)) |
| raw_data_manager.add_get_handler('message', |
| get_and_fixup_unknown_message_content) |
| |
| |
| def _prepare_set(msg, maintype, subtype, headers): |
| msg['Content-Type'] = '/'.join((maintype, subtype)) |
| if headers: |
| if not hasattr(headers[0], 'name'): |
| mp = msg.policy |
| headers = [mp.header_factory(*mp.header_source_parse([header])) |
| for header in headers] |
| try: |
| for header in headers: |
| if header.defects: |
| raise header.defects[0] |
| msg[header.name] = header |
| except email.errors.HeaderDefect as exc: |
| raise ValueError("Invalid header: {}".format( |
| header.fold(policy=msg.policy))) from exc |
| |
| |
| def _finalize_set(msg, disposition, filename, cid, params): |
| if disposition is None and filename is not None: |
| disposition = 'attachment' |
| if disposition is not None: |
| msg['Content-Disposition'] = disposition |
| if filename is not None: |
| msg.set_param('filename', |
| filename, |
| header='Content-Disposition', |
| replace=True) |
| if cid is not None: |
| msg['Content-ID'] = cid |
| if params is not None: |
| for key, value in params.items(): |
| msg.set_param(key, value) |
| |
| |
| # XXX: This is a cleaned-up version of base64mime.body_encode (including a bug |
| # fix in the calculation of unencoded_bytes_per_line). It would be nice to |
| # drop both this and quoprimime.body_encode in favor of enhanced binascii |
| # routines that accepted a max_line_length parameter. |
| def _encode_base64(data, max_line_length): |
| encoded_lines = [] |
| unencoded_bytes_per_line = max_line_length // 4 * 3 |
| for i in range(0, len(data), unencoded_bytes_per_line): |
| thisline = data[i:i+unencoded_bytes_per_line] |
| encoded_lines.append(binascii.b2a_base64(thisline).decode('ascii')) |
| return ''.join(encoded_lines) |
| |
| |
| def _encode_text(string, charset, cte, policy): |
| lines = string.encode(charset).splitlines() |
| linesep = policy.linesep.encode('ascii') |
| def embedded_body(lines): return linesep.join(lines) + linesep |
| def normal_body(lines): return b'\n'.join(lines) + b'\n' |
| if cte==None: |
| # Use heuristics to decide on the "best" encoding. |
| if max((len(x) for x in lines), default=0) <= policy.max_line_length: |
| try: |
| return '7bit', normal_body(lines).decode('ascii') |
| except UnicodeDecodeError: |
| pass |
| if policy.cte_type == '8bit': |
| return '8bit', normal_body(lines).decode('ascii', 'surrogateescape') |
| sniff = embedded_body(lines[:10]) |
| sniff_qp = quoprimime.body_encode(sniff.decode('latin-1'), |
| policy.max_line_length) |
| sniff_base64 = binascii.b2a_base64(sniff) |
| # This is a little unfair to qp; it includes lineseps, base64 doesn't. |
| if len(sniff_qp) > len(sniff_base64): |
| cte = 'base64' |
| else: |
| cte = 'quoted-printable' |
| if len(lines) <= 10: |
| return cte, sniff_qp |
| if cte == '7bit': |
| data = normal_body(lines).decode('ascii') |
| elif cte == '8bit': |
| data = normal_body(lines).decode('ascii', 'surrogateescape') |
| elif cte == 'quoted-printable': |
| data = quoprimime.body_encode(normal_body(lines).decode('latin-1'), |
| policy.max_line_length) |
| elif cte == 'base64': |
| data = _encode_base64(embedded_body(lines), policy.max_line_length) |
| else: |
| raise ValueError("Unknown content transfer encoding {}".format(cte)) |
| return cte, data |
| |
| |
| def set_text_content(msg, string, subtype="plain", charset='utf-8', cte=None, |
| disposition=None, filename=None, cid=None, |
| params=None, headers=None): |
| _prepare_set(msg, 'text', subtype, headers) |
| cte, payload = _encode_text(string, charset, cte, msg.policy) |
| msg.set_payload(payload) |
| msg.set_param('charset', |
| email.charset.ALIASES.get(charset, charset), |
| replace=True) |
| msg['Content-Transfer-Encoding'] = cte |
| _finalize_set(msg, disposition, filename, cid, params) |
| raw_data_manager.add_set_handler(str, set_text_content) |
| |
| |
| def set_message_content(msg, message, subtype="rfc822", cte=None, |
| disposition=None, filename=None, cid=None, |
| params=None, headers=None): |
| if subtype == 'partial': |
| raise ValueError("message/partial is not supported for Message objects") |
| if subtype == 'rfc822': |
| if cte not in (None, '7bit', '8bit', 'binary'): |
| # http://tools.ietf.org/html/rfc2046#section-5.2.1 mandate. |
| raise ValueError( |
| "message/rfc822 parts do not support cte={}".format(cte)) |
| # 8bit will get coerced on serialization if policy.cte_type='7bit'. We |
| # may end up claiming 8bit when it isn't needed, but the only negative |
| # result of that should be a gateway that needs to coerce to 7bit |
| # having to look through the whole embedded message to discover whether |
| # or not it actually has to do anything. |
| cte = '8bit' if cte is None else cte |
| elif subtype == 'external-body': |
| if cte not in (None, '7bit'): |
| # http://tools.ietf.org/html/rfc2046#section-5.2.3 mandate. |
| raise ValueError( |
| "message/external-body parts do not support cte={}".format(cte)) |
| cte = '7bit' |
| elif cte is None: |
| # http://tools.ietf.org/html/rfc2046#section-5.2.4 says all future |
| # subtypes should be restricted to 7bit, so assume that. |
| cte = '7bit' |
| _prepare_set(msg, 'message', subtype, headers) |
| msg.set_payload([message]) |
| msg['Content-Transfer-Encoding'] = cte |
| _finalize_set(msg, disposition, filename, cid, params) |
| raw_data_manager.add_set_handler(email.message.Message, set_message_content) |
| |
| |
| def set_bytes_content(msg, data, maintype, subtype, cte='base64', |
| disposition=None, filename=None, cid=None, |
| params=None, headers=None): |
| _prepare_set(msg, maintype, subtype, headers) |
| if cte == 'base64': |
| data = _encode_base64(data, max_line_length=msg.policy.max_line_length) |
| elif cte == 'quoted-printable': |
| # XXX: quoprimime.body_encode won't encode newline characters in data, |
| # so we can't use it. This means max_line_length is ignored. Another |
| # bug to fix later. (Note: encoders.quopri is broken on line ends.) |
| data = binascii.b2a_qp(data, istext=False, header=False, quotetabs=True) |
| data = data.decode('ascii') |
| elif cte == '7bit': |
| # Make sure it really is only ASCII. The early warning here seems |
| # worth the overhead...if you care write your own content manager :). |
| data.encode('ascii') |
| elif cte in ('8bit', 'binary'): |
| data = data.decode('ascii', 'surrogateescape') |
| msg.set_payload(data) |
| msg['Content-Transfer-Encoding'] = cte |
| _finalize_set(msg, disposition, filename, cid, params) |
| for typ in (bytes, bytearray, memoryview): |
| raw_data_manager.add_set_handler(typ, set_bytes_content) |
