/usr/share/pyshared/messaging/mms/mms_pdu.py is in python-messaging 0.5.11+debian-1.
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#
# It was originally distributed under the terms of the GNU Lesser
# General Public License Version 2.
#
# python-messaging opts to apply the terms of the ordinary GNU
# General Public License v2, as permitted by section 3 of the LGPL
# v2.1. This re-licensing allows the entirety of python-messaging to
# be distributed according to the terms of GPL-2.
#
# See the COPYING file included in this archive
"""MMS Data Unit structure encoding and decoding classes"""
from __future__ import with_statement
import array
import os
import random
from messaging.utils import debug
from messaging.mms import message, wsp_pdu
from messaging.mms.iterator import PreviewIterator
def flatten_list(x):
"""Flattens ``x`` into a single list"""
result = []
for el in x:
if hasattr(el, "__iter__") and not isinstance(el, basestring):
result.extend(flatten_list(el))
else:
result.append(el)
return result
mms_field_names = {
0x01: ('Bcc', 'encoded_string_value'),
0x02: ('Cc', 'encoded_string_value'),
0x03: ('Content-Location', 'uri_value'),
0x04: ('Content-Type', 'content_type_value'),
0x05: ('Date', 'date_value'),
0x06: ('Delivery-Report', 'boolean_value'),
0x07: ('Delivery-Time', None),
0x08: ('Expiry', 'expiry_value'),
0x09: ('From', 'from_value'),
0x0a: ('Message-Class', 'message_class_value'),
0x0b: ('Message-ID', 'text_string'),
0x0c: ('Message-Type', 'message_type_value'),
0x0d: ('MMS-Version', 'version_value'),
0x0e: ('Message-Size', 'long_integer'),
0x0f: ('Priority', 'priority_value'),
0x10: ('Read-Reply', 'boolean_value'),
0x11: ('Report-Allowed', 'boolean_value'),
0x12: ('Response-Status', 'response_status_value'),
0x13: ('Response-Text', 'encoded_string_value'),
0x14: ('Sender-Visibility', 'sender_visibility_value'),
0x15: ('Status', 'status_value'),
0x16: ('Subject', 'encoded_string_value'),
0x17: ('To', 'encoded_string_value'),
0x18: ('Transaction-Id', 'text_string'),
}
class MMSDecoder(wsp_pdu.Decoder):
"""A decoder for MMS messages"""
def __init__(self, filename=None):
"""
:param filename: If specified, decode the content of the MMS
message file with this name
:type filename: str
"""
self._mms_data = array.array('B')
self._mms_message = message.MMSMessage()
self._parts = []
def decode_file(self, filename):
"""
Load the data contained in the specified ``filename``, and decode it.
:param filename: The name of the MMS message file to open
:type filename: str
:raise OSError: The filename is invalid
:return: The decoded MMS data
:rtype: MMSMessage
"""
num_bytes = os.stat(filename)[6]
data = array.array('B')
with open(filename, 'rb') as f:
data.fromfile(f, num_bytes)
return self.decode_data(data)
def decode_data(self, data):
"""
Decode the specified MMS message data
:param data: The MMS message data to decode
:type data: array.array('B')
:return: The decoded MMS data
:rtype: MMSMessage
"""
self._mms_message = message.MMSMessage()
self._mms_data = data
body_iter = self.decode_message_header()
self.decode_message_body(body_iter)
return self._mms_message
def decode_message_header(self):
"""
Decodes the (full) MMS header data
This must be called before :func:`_decodeBody`, as it sets
certain internal variables relating to data lengths, etc.
"""
data_iter = PreviewIterator(self._mms_data)
# First 3 headers (in order
############################
# - X-Mms-Message-Type
# - X-Mms-Transaction-ID
# - X-Mms-Version
# TODO: reimplement strictness - currently we allow these 3 headers
# to be mixed with any of the other headers (this allows the
# decoding of "broken" MMSs, but is technically incorrect)
# Misc headers
##############
# The next few headers will not be in a specific order, except for
# "Content-Type", which should be the last header
# According to [4], MMS header field names will be short integers
content_type_found = False
header = ''
while content_type_found == False:
try:
header, value = self.decode_header(data_iter)
except StopIteration:
break
if header == mms_field_names[0x04][0]:
content_type_found = True
else:
self._mms_message.headers[header] = value
if header == 'Content-Type':
# Otherwise it might break Content-Location
# content_type, params = value
self._mms_message.headers[header] = value
return data_iter
def decode_message_body(self, data_iter):
"""
Decodes the MMS message body
:param data_iter: an iterator over the sequence of bytes of the MMS
body
:type data_iter: iter
"""
######### MMS body: headers ###########
# Get the number of data parts in the MMS body
try:
num_entries = self.decode_uint_var(data_iter)
except StopIteration:
return
#print 'Number of data entries (parts) in MMS body:', num_entries
########## MMS body: entries ##########
# For every data "part", we have to read the following sequence:
# <length of content-type + other possible headers>,
# <length of data>,
# <content-type + other possible headers>,
# <data>
for part_num in range(num_entries):
#print '\nPart %d:\n------' % part_num
headers_len = self.decode_uint_var(data_iter)
data_len = self.decode_uint_var(data_iter)
# Prepare to read content-type + other possible headers
ct_field_bytes = []
for i in range(headers_len):
ct_field_bytes.append(data_iter.next())
ct_iter = PreviewIterator(ct_field_bytes)
# Get content type
ctype, ct_parameters = self.decode_content_type_value(ct_iter)
headers = {'Content-Type': (ctype, ct_parameters)}
# Now read other possible headers until <headers_len> bytes
# have been read
while True:
try:
hdr, value = self.decode_header(ct_iter)
headers[hdr] = value
except StopIteration:
break
# Data (note: this is not null-terminated)
data = array.array('B')
for i in range(data_len):
data.append(data_iter.next())
part = message.DataPart()
part.set_data(data, ctype)
part.content_type_parameters = ct_parameters
part.headers = headers
self._mms_message.add_data_part(part)
@staticmethod
def decode_header(byte_iter):
"""
Decodes a header entry from an MMS message
starting at the byte pointed to by :func:`byte_iter.next`
From [4], section 7.1::
Header = MMS-header | Application-header
The return type of the "header value" depends on the header
itself; it is thus up to the function calling this to determine
what that type is (or at least compensate for possibly
different return value types).
:raise DecodeError: This uses :func:`decode_mms_header` and
:func:`decode_application_header`, and will raise this
exception under the same circumstances as
:func:`decode_application_header`. ``byte_iter`` will
not be modified in this case.
:return: The decoded header entry from the MMS, in the format:
(<str:header name>, <str/int/float:header value>)
:rtype: tuple
"""
try:
return MMSDecoder.decode_mms_header(byte_iter)
except wsp_pdu.DecodeError:
return wsp_pdu.Decoder.decode_header(byte_iter)
@staticmethod
def decode_mms_header(byte_iter):
"""
Decodes the MMS header pointed by ``byte_iter``
This method takes into account the assigned number values for MMS
field names, as specified in [4], section 7.3, table 8.
From [4], section 7.1::
MMS-header = MMS-field-name MMS-value
MMS-field-name = Short-integer
MMS-value = Bcc-value | Cc-value | Content-location-value | Content-type-value | etc
:raise wsp_pdu.DecodeError: The MMS field name could not be parsed.
``byte_iter`` will not be modified.
:return: The decoded MMS header, in the format:
(<str:MMS-field-name>, <str:MMS-value>)
:rtype: tuple
"""
# Get the MMS-field-name
mms_field_name = ''
preview = byte_iter.preview()
byte = wsp_pdu.Decoder.decode_short_integer_from_byte(preview)
if byte in mms_field_names:
byte_iter.next()
mms_field_name = mms_field_names[byte][0]
else:
byte_iter.reset_preview()
raise wsp_pdu.DecodeError('Invalid MMS Header: could '
'not decode MMS field name')
# Now get the MMS-value
mms_value = ''
try:
name = mms_field_names[byte][1]
mms_value = getattr(MMSDecoder, 'decode_%s' % name)(byte_iter)
except wsp_pdu.DecodeError, msg:
raise wsp_pdu.DecodeError('Invalid MMS Header: Could '
'not decode MMS-value: %s' % msg)
except:
raise RuntimeError('A fatal error occurred, probably due to an '
'unimplemented decoding operation. Tried to '
'decode header: %s' % mms_field_name)
return mms_field_name, mms_value
@staticmethod
def decode_encoded_string_value(byte_iter):
"""
Decodes the encoded string value pointed by ``byte_iter``
From [4], section 7.2.9::
Encoded-string-value = Text-string | Value-length Char-set Text-string
The Char-set values are registered by IANA as MIBEnum value.
This function is not fully implemented, in that it does not
have proper support for the Char-set values; it basically just
reads over that sequence of bytes, and ignores it (see code for
details) - any help with this will be greatly appreciated.
:return: The decoded text string
:rtype: str
"""
try:
# First try "Value-length Char-set Text-string"
value_length = wsp_pdu.Decoder.decode_value_length(byte_iter)
# TODO: add proper support for charsets...
try:
charset = wsp_pdu.Decoder.decode_well_known_charset(byte_iter)
except wsp_pdu.DecodeError, msg:
raise Exception('encoded_string_value decoding error - '
'Could not decode Charset value: %s' % msg)
return wsp_pdu.Decoder.decode_text_string(byte_iter)
except wsp_pdu.DecodeError:
# Fall back on just "Text-string"
return wsp_pdu.Decoder.decode_text_string(byte_iter)
@staticmethod
def decode_boolean_value(byte_iter):
"""
Decodes the boolean value pointed by ``byte_iter``
From [4], section 7.2.6::
Delivery-report-value = Yes | No
Yes = <Octet 128>
No = <Octet 129>
A lot of other yes/no fields use this encoding (read-reply,
report-allowed, etc)
:raise wsp_pdu.DecodeError: The boolean value could not be parsed.
``byte_iter`` will not be modified.
:return: The value for the field
:rtype: bool
"""
byte = byte_iter.preview()
if byte not in (128, 129):
byte_iter.reset_preview()
raise wsp_pdu.DecodeError('Error parsing boolean value '
'for byte: %s' % hex(byte))
byte = byte_iter.next()
return byte == 128
@staticmethod
def decode_from_value(byte_iter):
"""
Decodes the "From" value pointed by ``byte_iter``
From [4], section 7.2.11::
From-value = Value-length (Address-present-token Encoded-string-value | Insert-address-token )
Address-present-token = <Octet 128>
Insert-address-token = <Octet 129>
:return: The "From" address value
:rtype: str
"""
value_length = wsp_pdu.Decoder.decode_value_length(byte_iter)
# See what token we have
byte = byte_iter.next()
if byte == 129: # Insert-address-token
return '<not inserted>'
return MMSDecoder.decode_encoded_string_value(byte_iter)
@staticmethod
def decode_message_class_value(byte_iter):
"""
Decodes the "Message-Class" value pointed by ``byte_iter``
From [4], section 7.2.12::
Message-class-value = Class-identifier | Token-text
Class-identifier = Personal | Advertisement | Informational | Auto
Personal = <Octet 128>
Advertisement = <Octet 129>
Informational = <Octet 130>
Auto = <Octet 131>
The token-text is an extension method to the message class.
:return: The decoded message class
:rtype: str
"""
class_identifiers = {
128: 'Personal',
129: 'Advertisement',
130: 'Informational',
131: 'Auto',
}
byte = byte_iter.preview()
if byte in class_identifiers:
byte_iter.next()
return class_identifiers[byte]
byte_iter.reset_preview()
return wsp_pdu.Decoder.decode_token_text(byte_iter)
@staticmethod
def decode_message_type_value(byte_iter):
"""
Decodes the "Message-Type" value pointed by ``byte_iter``
Defined in [4], section 7.2.14.
:return: The decoded message type, or '<unknown>'
:rtype: str
"""
message_types = {
0x80: 'm-send-req',
0x81: 'm-send-conf',
0x82: 'm-notification-ind',
0x83: 'm-notifyresp-ind',
0x84: 'm-retrieve-conf',
0x85: 'm-acknowledge-ind',
0x86: 'm-delivery-ind',
}
byte = byte_iter.preview()
if byte in message_types:
byte_iter.next()
return message_types[byte]
byte_iter.reset_preview()
return '<unknown>'
@staticmethod
def decode_priority_value(byte_iter):
"""
Decode the "Priority" value pointed by ``byte_iter``
Defined in [4], section 7.2.17
:raise wsp_pdu.DecodeError: The priority value could not be decoded;
``byte_iter`` is not modified in this case.
:return: The decoded priority value
:rtype: str
"""
priorities = {128: 'Low', 129: 'Normal', 130: 'High'}
byte = byte_iter.preview()
if byte in priorities:
byte = byte_iter.next()
return priorities[byte]
byte_iter.reset_preview()
raise wsp_pdu.DecodeError('Error parsing Priority value '
'for byte: %s' % byte)
@staticmethod
def decode_sender_visibility_value(byte_iter):
"""
Decodes the sender visibility value pointed by ``byte_iter``
Defined in [4], section 7.2.22::
Sender-visibility-value = Hide | Show
Hide = <Octet 128>
Show = <Octet 129>
:raise wsp_pdu.DecodeError: The sender visibility value could not be
parsed. ``byte_iter`` will not be modified
in this case.
:return: The sender visibility: 'Hide' or 'Show'
:rtype: str
"""
byte = byte_iter.preview()
if byte not in (128, 129):
byte_iter.reset_preview()
raise wsp_pdu.DecodeError('Error parsing sender visibility '
'value for byte: %s' % hex(byte))
byte = byte_iter.next()
value = 'Hide' if byte == 128 else 'Show'
return value
@staticmethod
def decode_response_status_value(byte_iter):
"""
Decodes the "Response Status" value pointed by ``byte_iter``
Defined in [4], section 7.2.20
:raise wsp_pdu.DecodeError: The sender visibility value could not be
parsed. ``byte_iter`` will not be modified in
this case.
:return: The decoded Response-status-value
:rtype: str
"""
response_status_values = {
0x80: 'Ok',
0x81: 'Error-unspecified',
0x82: 'Error-service-denied',
0x83: 'Error-message-format-corrupt',
0x84: 'Error-sending-address-unresolved',
0x85: 'Error-message-not-found',
0x86: 'Error-network-problem',
0x87: 'Error-content-not-accepted',
0x88: 'Error-unsupported-message',
}
byte = byte_iter.preview()
byte_iter.next()
# Return error unspecified if it couldn't be decoded
return response_status_values.get(byte, 0x81)
@staticmethod
def decode_status_value(byte_iter):
"""
Used to decode the "Status" MMS header.
Defined in [4], section 7.2.23
:raise wsp_pdu.DecodeError: The sender visibility value could not be
parsed. ``byte_iter`` will not be
modified in this case.
:return: The decoded Status-value
:rtype: str
"""
status_values = {
0x80: 'Expired',
0x81: 'Retrieved',
0x82: 'Rejected',
0x83: 'Deferred',
0x84: 'Unrecognised',
}
byte = byte_iter.next()
# Return an unrecognised state if it couldn't be decoded
return status_values.get(byte, 0x84)
@staticmethod
def decode_expiry_value(byte_iter):
"""
Used to decode the "Expiry" MMS header.
From [4], section 7.2.10::
Expiry-value = Value-length (Absolute-token Date-value | Relative-token Delta-seconds-value)
Absolute-token = <Octet 128>
Relative-token = <Octet 129>
:raise wsp_pdu.DecodeError: The Expiry-value could not be decoded
:return: The decoded Expiry-value, either as a date, or as a delta-seconds value
:rtype: str or int
"""
value_length = MMSDecoder.decode_value_length(byte_iter)
token = byte_iter.next()
if token == 0x80: # Absolute-token
return MMSDecoder.decode_date_value(byte_iter)
elif token == 0x81: # Relative-token
return MMSDecoder.decode_delta_seconds_value(byte_iter)
raise wsp_pdu.DecodeError('Unrecognized token value: %s' % hex(token))
class MMSEncoder(wsp_pdu.Encoder):
"""MMS Encoder"""
def __init__(self):
self._mms_message = message.MMSMessage()
def encode(self, mms_message):
"""
Encodes the specified MMS message ``mms_message``
:param mms_message: The MMS message to encode
:type mms_message: MMSMessage
:return: The binary-encoded MMS data, as a sequence of bytes
:rtype: array.array('B')
"""
self._mms_message = mms_message
msg_data = self.encode_message_header()
msg_data.extend(self.encode_message_body())
return msg_data
def encode_message_header(self):
"""
Binary-encodes the MMS header data.
The encoding used for the MMS header is specified in [4].
All "constant" encoded values found/used in this method
are also defined in [4]. For a good example, see [2].
:return: the MMS PDU header, as an array of bytes
:rtype: array.array('B')
"""
# See [4], chapter 8 for info on how to use these
# from_types = {'Address-present-token': 0x80,
# 'Insert-address-token': 0x81}
# content_types = {'application/vnd.wap.multipart.related': 0xb3}
# Create an array of 8-bit values
message_header = array.array('B')
headers_to_encode = self._mms_message.headers
# If the user added any of these to the message manually
# (X- prefix) use those instead
for hdr in ('X-Mms-Message-Type', 'X-Mms-Transaction-Id',
'X-Mms-Version'):
if hdr in headers_to_encode:
if hdr == 'X-Mms-Version':
clean_header = 'MMS-Version'
else:
clean_header = hdr.replace('X-Mms-', '', 1)
headers_to_encode[clean_header] = headers_to_encode[hdr]
del headers_to_encode[hdr]
# First 3 headers (in order), according to [4]:
################################################
# - X-Mms-Message-Type
# - X-Mms-Transaction-ID
# - X-Mms-Version
### Start of Message-Type verification
if 'Message-Type' not in headers_to_encode:
# Default to 'm-retrieve-conf'; we don't need a To/CC field for
# this (see WAP-209, section 6.3, table 5)
headers_to_encode['Message-Type'] = 'm-retrieve-conf'
# See if the chosen message type is valid, given the message's
# other headers. NOTE: we only distinguish between 'm-send-req'
# (requires a destination number) and 'm-retrieve-conf'
# (requires no destination number) - if "Message-Type" is
# something else, we assume the message creator knows
# what she is doing
if headers_to_encode['Message-Type'] == 'm-send-req':
found_dest_address = False
for address_type in ('To', 'Cc', 'Bc'):
if address_type in headers_to_encode:
found_dest_address = True
break
if not found_dest_address:
headers_to_encode['Message-Type'] = 'm-retrieve-conf'
### End of Message-Type verification
### Start of Transaction-Id verification
if 'Transaction-Id' not in headers_to_encode:
trans_id = str(random.randint(1000, 9999))
headers_to_encode['Transaction-Id'] = trans_id
### End of Transaction-Id verification
### Start of MMS-Version verification
if 'MMS-Version' not in headers_to_encode:
headers_to_encode['MMS-Version'] = '1.0'
# Encode the first three headers, in correct order
for hdr in ('Message-Type', 'Transaction-Id', 'MMS-Version'):
message_header.extend(
MMSEncoder.encode_header(hdr, headers_to_encode[hdr]))
del headers_to_encode[hdr]
# Encode all remaining MMS message headers, except "Content-Type"
# -- this needs to be added last, according [2] and [4]
for hdr in headers_to_encode:
if hdr != 'Content-Type':
message_header.extend(
MMSEncoder.encode_header(hdr, headers_to_encode[hdr]))
# Ok, now only "Content-type" should be left
content_type, ct_parameters = headers_to_encode['Content-Type']
message_header.extend(MMSEncoder.encode_mms_field_name('Content-Type'))
ret = MMSEncoder.encode_content_type_value(content_type, ct_parameters)
message_header.extend(flatten_list(ret))
return message_header
def encode_message_body(self):
"""
Binary-encodes the MMS body data
The MMS body's header should not be confused with the actual
MMS header, as returned by :func:`encode_header`.
The encoding used for the MMS body is specified in [5],
section 8.5. It is only referenced in [4], however [2]
provides a good example of how this ties in with the MMS
header encoding.
The MMS body is of type `application/vnd.wap.multipart` ``mixed``
or ``related``. As such, its structure is divided into a header, and
the data entries/parts::
[ header ][ entries ]
^^^^^^^^^^^^^^^^^^^^^
MMS Body
The MMS Body header consists of one entry[5]::
name type purpose
------- ------- -----------
num_entries uint_var num of entries in the multipart entity
The MMS body's multipart entries structure::
name type purpose
------- ----- -----------
HeadersLen uint_var length of the ContentType and
Headers fields combined
DataLen uint_var length of the Data field
ContentType Multiple octets the content type of the data
Headers (<HeadersLen>
- length of
<ContentType>) octets the part's headers
Data <DataLen> octets the part's data
:return: The binary-encoded MMS PDU body, as an array of bytes
:rtype: array.array('B')
"""
message_body = array.array('B')
#TODO: enable encoding of MMSs without SMIL file
########## MMS body: header ##########
# Parts: SMIL file + <number of data elements in each slide>
num_entries = 1
for page in self._mms_message._pages:
num_entries += page.number_of_parts()
for data_part in self._mms_message._data_parts:
num_entries += 1
message_body.extend(self.encode_uint_var(num_entries))
########## MMS body: entries ##########
# For every data "part", we have to add the following sequence:
# <length of content-type + other possible headers>,
# <length of data>,
# <content-type + other possible headers>,
# <data>.
# Gather the data parts, adding the MMS message's SMIL file
smil_part = message.DataPart()
smil = self._mms_message.smil()
smil_part.set_data(smil, 'application/smil')
#TODO: make this dynamic....
smil_part.headers['Content-ID'] = '<0000>'
parts = [smil_part]
for slide in self._mms_message._pages:
for part_tuple in (slide.image, slide.audio, slide.text):
if part_tuple is not None:
parts.append(part_tuple[0])
for part in parts:
name, val_type = part.headers['Content-Type']
part_content_type = self.encode_content_type_value(name, val_type)
encoded_part_headers = []
for hdr in part.headers:
if hdr == 'Content-Type':
continue
encoded_part_headers.extend(
wsp_pdu.Encoder.encode_header(hdr, part.headers[hdr]))
# HeadersLen entry (length of the ContentType and
# Headers fields combined)
headers_len = len(part_content_type) + len(encoded_part_headers)
message_body.extend(self.encode_uint_var(headers_len))
# DataLen entry (length of the Data field)
message_body.extend(self.encode_uint_var(len(part)))
# ContentType entry
message_body.extend(part_content_type)
# Headers
message_body.extend(encoded_part_headers)
# Data (note: we do not null-terminate this)
for char in part.data:
message_body.append(ord(char))
return message_body
@staticmethod
def encode_header(header_field_name, header_value):
"""
Encodes a header entry for an MMS message
The return type of the "header value" depends on the header
itself; it is thus up to the function calling this to determine
what that type is (or at least compensate for possibly different
return value types).
From [4], section 7.1::
Header = MMS-header | Application-header
MMS-header = MMS-field-name MMS-value
MMS-field-name = Short-integer
MMS-value = Bcc-value | Cc-value | Content-location-value | Content-type-value | etc
:raise DecodeError: This uses :func:`decode_mms_header` and
:func:`decode_application_header`, and will raise this
exception under the same circumstances as
:func:`decode_application_header`. ``byte_iter`` will
not be modified in this case.
:return: The decoded header entry from the MMS, in the format:
(<str:header name>, <str/int/float:header value>)
:rtype: tuple
"""
encoded_header = []
# First try encoding the header as a "MMS-header"...
for assigned_number in mms_field_names:
header = mms_field_names[assigned_number][0]
if header == header_field_name:
encoded_header.extend(
wsp_pdu.Encoder.encode_short_integer(assigned_number))
# Now encode the value
expected_type = mms_field_names[assigned_number][1]
try:
ret = getattr(MMSEncoder,
'encode_%s' % expected_type)(header_value)
encoded_header.extend(ret)
except wsp_pdu.EncodeError, msg:
raise wsp_pdu.EncodeError('Error encoding parameter '
'value: %s' % msg)
except:
debug('A fatal error occurred, probably due to an '
'unimplemented encoding operation')
raise
break
# See if the "MMS-header" encoding worked
if not len(encoded_header):
# ...it didn't. Use "Application-header" encoding
header_name = wsp_pdu.Encoder.encode_token_text(header_field_name)
encoded_header.extend(header_name)
# Now add the value
encoded_header.extend(
wsp_pdu.Encoder.encode_text_string(header_value))
return encoded_header
@staticmethod
def encode_mms_field_name(field_name):
"""
Encodes an MMS header field name
From [4], section 7.1::
MMS-field-name = Short-integer
:raise EncodeError: The specified header field name is not a
well-known MMS header.
:param field_name: The header field name to encode
:type field_name: str
:return: The encoded header field name, as a sequence of bytes
:rtype: list
"""
encoded_mms_field_name = []
for assigned_number in mms_field_names:
if mms_field_names[assigned_number][0] == field_name:
encoded_mms_field_name.extend(
wsp_pdu.Encoder.encode_short_integer(assigned_number))
break
if not len(encoded_mms_field_name):
raise wsp_pdu.EncodeError('The specified header field name is not '
'a well-known MMS header field name')
return encoded_mms_field_name
@staticmethod
def encode_from_value(from_value=''):
"""
Encodes the "From" address value
From [4], section 7.2.11::
From-value = Value-length (Address-present-token Encoded-string-value | Insert-address-token )
Address-present-token = <Octet 128>
Insert-address-token = <Octet 129>
:param from_value: The "originator" of the MMS message. This may be an
empty string, in which case a token will be encoded
informing the MMSC to insert the address of the
device that sent this message (default).
:type from_value: str
:return: The encoded "From" address value, as a sequence of bytes
:rtype: list
"""
encoded_from_value = []
if len(from_value) == 0:
value_length = wsp_pdu.Encoder.encode_value_length(1)
encoded_from_value.extend(value_length)
encoded_from_value.append(129) # Insert-address-token
else:
encoded_address = MMSEncoder.encode_encoded_string_value(from_value)
# the "+1" is for the Address-present-token
length = len(encoded_address) + 1
value_length = wsp_pdu.Encoder.encode_value_length(length)
encoded_from_value.extend(value_length)
encoded_from_value.append(128) # Address-present-token
encoded_from_value.extend(encoded_address)
return encoded_from_value
@staticmethod
def encode_encoded_string_value(string_value):
"""
Encodes ``string_value``
This is a simple wrapper to :func:`encode_text_string`
From [4], section 7.2.9::
Encoded-string-value = Text-string | Value-length Char-set Text-string
The Char-set values are registered by IANA as MIBEnum value.
:param string_value: The text string to encode
:type string_value: str
:return: The encoded string value, as a sequence of bytes
:rtype: list
"""
return wsp_pdu.Encoder.encode_text_string(string_value)
@staticmethod
def encode_message_type_value(message_type):
"""
Encodes the Message-Type value ``message_type``
Unknown message types are discarded; thus they will be encoded
as 0x80 ("m-send-req") by this function
Defined in [4], section 7.2.14.
:param message_type: The MMS message type to encode
:type message_type: str
:return: The encoded message type, as a sequence of bytes
:rtype: list
"""
message_types = {
'm-send-req': 0x80,
'm-send-conf': 0x81,
'm-notification-ind': 0x82,
'm-notifyresp-ind': 0x83,
'm-retrieve-conf': 0x84,
'm-acknowledge-ind': 0x85,
'm-delivery-ind': 0x86,
}
return [message_types.get(message_type, 0x80)]
@staticmethod
def encode_status_value(status_value):
status_values = {
'Expired': 0x80,
'Retrieved': 0x81,
'Rejected': 0x82,
'Deferred': 0x83,
'Unrecognised': 0x84,
}
# Return an unrecognised state if it couldn't be decoded
return [status_values.get(status_value, 'Unrecognised')]
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