Telethon/telethon_generator/parser/tl_object.py
2017-09-23 20:07:40 +02:00

291 lines
12 KiB
Python

import re
from zlib import crc32
class TLObject:
""".tl core types IDs (such as vector, booleans, etc.)"""
CORE_TYPES = (
0xbc799737, # boolFalse#bc799737 = Bool;
0x997275b5, # boolTrue#997275b5 = Bool;
0x3fedd339, # true#3fedd339 = True;
0x1cb5c415, # vector#1cb5c415 {t:Type} # [ t ] = Vector t;
)
def __init__(self, fullname, object_id, args, result, is_function):
"""
Initializes a new TLObject, given its properties.
Usually, this will be called from `from_tl` instead
:param fullname: The fullname of the TL object (namespace.name)
The namespace can be omitted
:param object_id: The hexadecimal string representing the object ID
:param args: The arguments, if any, of the TL object
:param result: The result type of the TL object
:param is_function: Is the object a function or a type?
"""
# The name can or not have a namespace
if '.' in fullname:
self.namespace = fullname.split('.')[0]
self.name = fullname.split('.')[1]
else:
self.namespace = None
self.name = fullname
self.args = args
self.result = result
self.is_function = is_function
# The ID should be an hexadecimal string or None to be inferred
if object_id is None:
self.id = self.infer_id()
else:
self.id = int(object_id, base=16)
assert self.id == self.infer_id(),\
'Invalid inferred ID for ' + repr(self)
@staticmethod
def from_tl(tl, is_function):
"""Returns a TL object from the given TL scheme line"""
# Regex to match the whole line
match = re.match(r'''
^ # We want to match from the beginning to the end
([\w.]+) # The .tl object can contain alpha_name or namespace.alpha_name
(?:
\# # After the name, comes the ID of the object
([0-9a-f]+) # The constructor ID is in hexadecimal form
)? # If no constructor ID was given, CRC32 the 'tl' to determine it
(?:\s # After that, we want to match its arguments (name:type)
{? # For handling the start of the '{X:Type}' case
\w+ # The argument name will always be an alpha-only name
: # Then comes the separator between name:type
[\w\d<>#.?!]+ # The type is slightly more complex, since it's alphanumeric and it can
# also have Vector<type>, flags:# and flags.0?default, plus :!X as type
}? # For handling the end of the '{X:Type}' case
)* # Match 0 or more arguments
\s # Leave a space between the arguments and the equal
=
\s # Leave another space between the equal and the result
([\w\d<>#.?]+) # The result can again be as complex as any argument type
;$ # Finally, the line should always end with ;
''', tl, re.IGNORECASE | re.VERBOSE)
if match is None:
# Probably "vector#1cb5c415 {t:Type} # [ t ] = Vector t;"
raise ValueError('Cannot parse TLObject', tl)
# Sub-regex to match the arguments (sadly, it cannot be embedded in the first regex)
args_match = re.findall(r'''
({)? # We may or may not capture the opening brace
(\w+) # First we capture any alpha name with length 1 or more
: # Which is separated from its type by a colon
([\w\d<>#.?!]+) # The type is slightly more complex, since it's alphanumeric and it can
# also have Vector<type>, flags:# and flags.0?default, plus :!X as type
(})? # We may or not capture the closing brace
''', tl, re.IGNORECASE | re.VERBOSE)
# Retrieve the matched arguments
args = [TLArg(name, arg_type, brace != '')
for brace, name, arg_type, _ in args_match]
# And initialize the TLObject
return TLObject(
fullname=match.group(1),
object_id=match.group(2),
args=args,
result=match.group(3),
is_function=is_function)
def class_name(self):
"""Gets the class name following the Python style guidelines"""
# Courtesy of http://stackoverflow.com/a/31531797/4759433
result = re.sub(r'_([a-z])', lambda m: m.group(1).upper(), self.name)
result = result[:1].upper() + result[1:].replace('_', '')
# If it's a function, let it end with "Request" to identify them
if self.is_function:
result += 'Request'
return result
def sorted_args(self):
"""Returns the arguments properly sorted and ready to plug-in
into a Python's method header (i.e., flags and those which
can be inferred will go last so they can default =None)
"""
return sorted(self.args,
key=lambda x: x.is_flag or x.can_be_inferred)
def is_core_type(self):
"""Determines whether the TLObject is a "core type"
(and thus should be embedded in the generated code) or not"""
return self.id in TLObject.CORE_TYPES
def __repr__(self, ignore_id=False):
fullname = ('{}.{}'.format(self.namespace, self.name)
if self.namespace is not None else self.name)
if getattr(self, 'id', None) is None or ignore_id:
hex_id = ''
else:
# Skip 0x and add 0's for padding
hex_id = '#' + hex(self.id)[2:].rjust(8, '0')
if self.args:
args = ' ' + ' '.join([repr(arg) for arg in self.args])
else:
args = ''
return '{}{}{} = {}'.format(fullname, hex_id, args, self.result)
def infer_id(self):
representation = self.__repr__(ignore_id=True)
# Clean the representation
representation = representation\
.replace(':bytes ', ':string ')\
.replace('?bytes ', '?string ')\
.replace('<', ' ').replace('>', '')\
.replace('{', '').replace('}', '')
representation = re.sub(
r' \w+:flags\.\d+\?true',
r'',
representation
)
return crc32(representation.encode('ascii'))
def __str__(self):
fullname = ('{}.{}'.format(self.namespace, self.name)
if self.namespace is not None else self.name)
# Some arguments are not valid for being represented, such as the flag indicator or generic definition
# (these have no explicit values until used)
valid_args = [arg for arg in self.args
if not arg.flag_indicator and not arg.generic_definition]
args = ', '.join(['{}={{}}'.format(arg.name) for arg in valid_args])
# Since Python's default representation for lists is using repr(), we need to str() manually on every item
args_format = ', '.join(
['str(self.{})'.format(arg.name) if not arg.is_vector else
'None if not self.{0} else [str(_) for _ in self.{0}]'.format(
arg.name) for arg in valid_args])
return ("'({} (ID: {}) = ({}))'.format({})"
.format(fullname, hex(self.id), args, args_format))
class TLArg:
def __init__(self, name, arg_type, generic_definition):
"""
Initializes a new .tl argument
:param name: The name of the .tl argument
:param arg_type: The type of the .tl argument
:param generic_definition: Is the argument a generic definition?
(i.e. {X:Type})
"""
if name == 'self': # This very only name is restricted
self.name = 'is_self'
else:
self.name = name
# Default values
self.is_vector = False
self.is_flag = False
self.flag_index = -1
# Special case: some types can be inferred, which makes it
# less annoying to type. Currently the only type that can
# be inferred is if the name is 'random_id', to which a
# random ID will be assigned if left as None (the default)
self.can_be_inferred = name == 'random_id'
# The type can be an indicator that other arguments will be flags
if arg_type == '#':
self.flag_indicator = True
self.type = None
self.is_generic = False
else:
self.flag_indicator = False
self.is_generic = arg_type.startswith('!')
# Strip the exclamation mark always to have only the name
self.type = arg_type.lstrip('!')
# The type may be a flag (flags.IDX?REAL_TYPE)
# Note that 'flags' is NOT the flags name; this is determined by a previous argument
# However, we assume that the argument will always be called 'flags'
flag_match = re.match(r'flags.(\d+)\?([\w<>.]+)', self.type)
if flag_match:
self.is_flag = True
self.flag_index = int(flag_match.group(1))
# Update the type to match the exact type, not the "flagged" one
self.type = flag_match.group(2)
# Then check if the type is a Vector<REAL_TYPE>
vector_match = re.match(r'vector<(\w+)>', self.type, re.IGNORECASE)
if vector_match:
self.is_vector = True
# If the type's first letter is not uppercase, then
# it is a constructor and we use (read/write) its ID
# as pinpointed on issue #81.
self.use_vector_id = self.type[0] == 'V'
# Update the type to match the one inside the vector
self.type = vector_match.group(1)
# The name may contain "date" in it, if this is the case and the type is "int",
# we can safely assume that this should be treated as a "date" object.
# Note that this is not a valid Telegram object, but it's easier to work with
if self.type == 'int' and (
re.search(r'(\b|_)date\b', name) or
name in ('expires', 'expires_at', 'was_online')):
self.type = 'date'
self.generic_definition = generic_definition
def type_hint(self):
result = {
'int': 'int',
'long': 'int',
'string': 'str',
'date': 'datetime.datetime | None', # None date = 0 timestamp
'bytes': 'bytes',
'true': 'bool',
}.get(self.type, 'TLObject')
if self.is_vector:
result = 'list[{}]'.format(result)
if self.is_flag and self.type != 'date':
result += ' | None'
return result
def __str__(self):
# Find the real type representation by updating it as required
real_type = self.type
if self.flag_indicator:
real_type = '#'
if self.is_vector:
if self.use_vector_id:
real_type = 'Vector<{}>'.format(real_type)
else:
real_type = 'vector<{}>'.format(real_type)
if self.is_generic:
real_type = '!{}'.format(real_type)
if self.is_flag:
real_type = 'flags.{}?{}'.format(self.flag_index, real_type)
if self.generic_definition:
return '{{{}:{}}}'.format(self.name, real_type)
else:
return '{}:{}'.format(self.name, real_type)
def __repr__(self):
# Get rid of our special type
return str(self)\
.replace(':date', ':int')\
.replace('?date', '?int')