def _to_struct_internal_rep(
*, value: Any, tf_function_cache: MutableMapping[str, Any],
type_spec: computation_types.StructType,
device: tf.config.LogicalDevice) -> structure.Struct:
"""Converts a python container to internal representation for TF executor."""
type_iterator = structure.iter_elements(type_spec)
value_struct = structure.from_container(value)
value_iterator = structure.iter_elements(value_struct)
if len(type_spec) != len(value_struct):
raise TypeError('Mismatched number of elements between type spec and value '
'in `to_representation_for_type`. Type spec has {} '
'elements, value has {}.'.format(
len(type_spec), len(value_struct)))
result_elem = []
for (type_name, elem_type), (val_name,
elem_val) in zip(type_iterator, value_iterator):
if val_name is not None and type_name != val_name:
raise TypeError(
'Mismatching element names in type vs. value: {} vs. {}.'.format(
type_name, val_name))
elem_repr = to_representation_for_type(elem_val, tf_function_cache,
elem_type, device)
result_elem.append((type_name, elem_repr))
return structure.Struct(result_elem)
def is_valid_bitwidth_type_for_value_type(
bitwidth_type: computation_types.Type,
value_type: computation_types.Type) -> bool:
"""Whether or not `bitwidth_type` is a valid bitwidth type for `value_type`."""
# NOTE: this function is primarily a helper for `intrinsic_factory.py`'s
# `federated_secure_sum` function.
py_typecheck.check_type(bitwidth_type, computation_types.Type)
py_typecheck.check_type(value_type, computation_types.Type)
if value_type.is_tensor() and bitwidth_type.is_tensor():
# Here, `value_type` refers to a tensor. Rather than check that
# `bitwidth_type` is exactly the same, we check that it is a single integer,
# since we want a single bitwidth integer per tensor.
return bitwidth_type.dtype.is_integer and (
bitwidth_type.shape.num_elements() == 1)
elif value_type.is_struct() and bitwidth_type.is_struct():
bitwidth_name_and_types = list(structure.iter_elements(bitwidth_type))
value_name_and_types = list(structure.iter_elements(value_type))
if len(bitwidth_name_and_types) != len(value_name_and_types):
return False
for (inner_bitwidth_name,
inner_bitwidth_type), (inner_value_name, inner_value_type) in zip(
bitwidth_name_and_types, value_name_and_types):
if inner_bitwidth_name != inner_value_name:
return False
if not is_valid_bitwidth_type_for_value_type(inner_bitwidth_type,
inner_value_type):
return False
return True
else:
return False
def is_valid_bitwidth_type_for_value_type(
bitwidth_type: computation_types.Type,
value_type: computation_types.Type) -> bool:
"""Whether or not `bitwidth_type` is a valid bitwidth type for `value_type`."""
# NOTE: this function is primarily a helper for `intrinsic_factory.py`'s
# `federated_secure_sum` function.
py_typecheck.check_type(bitwidth_type, computation_types.Type)
py_typecheck.check_type(value_type, computation_types.Type)
if bitwidth_type.is_tensor():
# This condition applies to both `value_type` being a tensor or structure,
# as the same integer bitwidth can be used for all values in the structure.
return bitwidth_type.dtype.is_integer and (
bitwidth_type.shape.num_elements() == 1)
elif value_type.is_struct() and bitwidth_type.is_struct():
bitwidth_name_and_types = list(structure.iter_elements(bitwidth_type))
value_name_and_types = list(structure.iter_elements(value_type))
if len(bitwidth_name_and_types) != len(value_name_and_types):
return False
for (inner_bitwidth_name,
inner_bitwidth_type), (inner_value_name, inner_value_type) in zip(
bitwidth_name_and_types, value_name_and_types):
if inner_bitwidth_name != inner_value_name:
return False
if not is_valid_bitwidth_type_for_value_type(inner_bitwidth_type,
inner_value_type):
return False
return True
else:
return False
def is_single_integer_or_matches_structure(
type_sig: computation_types.Type,
shape_type: computation_types.Type) -> bool:
"""If `type_sig` is an integer or integer structure matching `shape_type`."""
py_typecheck.check_type(type_sig, computation_types.Type)
py_typecheck.check_type(shape_type, computation_types.Type)
if type_sig.is_tensor():
# This condition applies to both `shape_type` being a tensor or structure,
# as the same integer bitwidth can be used for all values in the structure.
return type_sig.dtype.is_integer and (type_sig.shape.num_elements() == 1)
elif shape_type.is_struct() and type_sig.is_struct():
bitwidth_name_and_types = list(structure.iter_elements(type_sig))
shape_name_and_types = list(structure.iter_elements(shape_type))
if len(type_sig) != len(shape_name_and_types):
return False
for (inner_name, type_sig), (inner_shape_name, inner_shape_type) in zip(
bitwidth_name_and_types, shape_name_and_types):
if inner_name != inner_shape_name:
return False
if not is_single_integer_or_matches_structure(type_sig, inner_shape_type):
return False
return True
else:
return False
def _serialize_struct_type(
struct_typed_value: Any,
type_spec: computation_types.StructType,
) -> computation_types.StructType:
"""Serializes a value of tuple type."""
value_structure = structure.from_container(struct_typed_value)
if len(value_structure) != len(type_spec):
raise TypeError(
'Cannot serialize a struct value of '
f'{len(value_structure)} elements to a struct type '
f'requiring {len(type_spec)} elements. Trying to serialize'
f'\n{struct_typed_value!r}\nto\n{type_spec}.')
type_elem_iter = structure.iter_elements(type_spec)
val_elem_iter = structure.iter_elements(value_structure)
elements = []
for (e_name, e_type), (_, e_val) in zip(type_elem_iter, val_elem_iter):
e_value, _ = serialize_value(e_val, e_type)
if e_name:
element = executor_pb2.Value.Struct.Element(name=e_name,
value=e_value)
else:
element = executor_pb2.Value.Struct.Element(value=e_value)
elements.append(element)
value_proto = executor_pb2.Value(struct=executor_pb2.Value.Struct(
element=elements))
return value_proto, type_spec
def from_tff_result(cls, struct):
py_typecheck.check_type(struct, structure.Struct)
return cls(
[value for _, value in structure.iter_elements(struct.trainable)],
[
value
for _, value in structure.iter_elements(struct.non_trainable)
])
async def create_struct(self, elements):
elements_as_structure = structure.from_container(elements)
elements_iter = structure.iter_elements(elements_as_structure)
pairs = ((n, v.internal_representation) for (n, v) in elements_iter)
inner_elements = structure.Struct(pairs)
return await self._delegate(
self._target_executor.create_struct(inner_elements))
def _create_structure_of_coro_references(
coro: Coroutine[Any, Any,
Any], type_signature: computation_types.Type) -> Any:
"""Returns a structure of `tff.program.CoroValueReference`s."""
py_typecheck.check_type(type_signature, computation_types.Type)
if type_signature.is_struct():
async def _to_structure(coro: Coroutine[Any, Any, Any]) -> structure.Struct:
return structure.from_container(await coro)
coro = _to_structure(coro)
shared_awaitable = async_utils.SharedAwaitable(coro)
async def _get_item(awaitable: Awaitable[structure.Struct],
index: int) -> Any:
value = await awaitable
return value[index]
elements = []
element_types = structure.iter_elements(type_signature)
for index, (name, element_type) in enumerate(element_types):
element_coro = _get_item(shared_awaitable, index)
element = _create_structure_of_coro_references(element_coro, element_type)
elements.append((name, element))
return structure.Struct(elements)
elif (type_signature.is_federated() and
type_signature.placement == placements.SERVER):
return _create_structure_of_coro_references(coro, type_signature.member)
elif type_signature.is_sequence():
return CoroValueReference(coro, type_signature)
elif type_signature.is_tensor():
return CoroValueReference(coro, type_signature)
else:
raise NotImplementedError(f'Unexpected type found: {type_signature}.')
async def _materialize_structure_of_value_references(
value: Any, type_signature: computation_types.Type) -> Any:
"""Returns a structure of materialized values."""
py_typecheck.check_type(type_signature, computation_types.Type)
async def _materialize(value: Any) -> Any:
if isinstance(value, value_reference.MaterializableValueReference):
return await value.get_value()
else:
return value
if type_signature.is_struct():
value = structure.from_container(value)
element_types = list(structure.iter_elements(type_signature))
element_coros = [
_materialize_structure_of_value_references(v, t)
for v, (_, t) in zip(value, element_types)
]
elements = await asyncio.gather(*element_coros)
elements = [(n, v) for v, (n, _) in zip(elements, element_types)]
return structure.Struct(elements)
elif (type_signature.is_federated() and
type_signature.placement == placements.SERVER):
return await _materialize_structure_of_value_references(
value, type_signature.member)
elif type_signature.is_sequence():
return await _materialize(value)
elif type_signature.is_tensor():
return await _materialize(value)
else:
return value
def _repackage_partitioned_values(after_merge_results,
result_type_spec: computation_types.Type):
"""Inverts `_split_value_into_subrounds` above."""
py_typecheck.check_type(after_merge_results, list)
if result_type_spec.is_struct():
after_merge_structs = [
structure.from_container(x) for x in after_merge_results
]
result_container = []
for idx, (name, elem_type) in enumerate(
structure.iter_elements(result_type_spec)):
result_container.append(
(name,
_repackage_partitioned_values(
[x[idx] for x in after_merge_structs], elem_type)))
return structure.Struct(result_container)
elif result_type_spec.is_federated(
) and result_type_spec.placement.is_clients():
if result_type_spec.all_equal:
return after_merge_results[0]
for x in after_merge_results:
py_typecheck.check_type(x, (list, tuple))
# Merges all clients-placed values back together.
return functools.reduce(lambda x, y: x + y, after_merge_results)
else:
return after_merge_results[0]
async def create_struct(
self, elements: List[executor_value_base.ExecutorValue]
) -> executor_value_base.ExecutorValue:
"""Creates an embedded tuple of the given `elements`.
Args:
elements: A collection of embedded values.
Returns:
An instance of `executor_value_base.ExecutorValue` representing the
embedded tuple.
Raises:
TypeError: If the `elements` are not embedded in the executor.
"""
element_values = []
element_types = []
for name, value in structure.iter_elements(
structure.from_container(elements)):
py_typecheck.check_type(value, executor_value_base.ExecutorValue)
element_values.append((name, value.internal_representation))
if name is not None:
element_types.append((name, value.type_signature))
else:
element_types.append(value.type_signature)
value = structure.Struct(element_values)
type_signature = computation_types.StructType(element_types)
return self._strategy.ingest_value(value, type_signature)
async def _zip(self, arg, placement, all_equal):
self._check_arg_is_structure(arg)
py_typecheck.check_type(placement, placement_literals.PlacementLiteral)
self._check_strategy_compatible_with_placement(placement)
children = self._target_executors[placement]
cardinality = len(children)
elements = structure.to_elements(arg.internal_representation)
for _, v in elements:
py_typecheck.check_type(v, list)
if len(v) != cardinality:
raise RuntimeError('Expected {} items, found {}.'.format(
cardinality, len(v)))
new_vals = []
for idx in range(cardinality):
new_vals.append(
structure.Struct([(k, v[idx]) for k, v in elements]))
new_vals = await asyncio.gather(
*[c.create_struct(x) for c, x in zip(children, new_vals)])
return FederatedResolvingStrategyValue(
new_vals,
computation_types.FederatedType(computation_types.StructType(
((k, v.member) if k else v.member
for k, v in structure.iter_elements(arg.type_signature))),
placement,
all_equal=all_equal))
def _serialize_struct_type(
struct_typed_value: Any,
type_spec: computation_types.StructType) -> _SerializeReturnType:
"""Serializes a value of tuple type."""
type_elem_iter = structure.iter_elements(type_spec)
val_elem_iter = structure.iter_elements(
structure.from_container(struct_typed_value))
tup_elems = []
for (e_name, e_type), (_, e_val) in zip(type_elem_iter, val_elem_iter):
e_proto, _ = serialize_value(e_val, e_type)
tup_elems.append(
executor_pb2.Value.Struct.Element(name=e_name if e_name else None,
value=e_proto))
result_proto = (executor_pb2.Value(struct=executor_pb2.Value.Struct(
element=tup_elems)))
return result_proto, type_spec
def _remove_struct_element_names_from_tff_type(type_spec):
"""Removes names of struct elements from `type_spec`.
Args:
type_spec: An instance of `computation_types.Type` that must be a tensor, a
(possibly) nested structure of tensors, or a function.
Returns:
A modified version of `type_spec` with element names in stuctures removed.
Raises:
TypeError: if arg is of the wrong type.
"""
if type_spec is None:
return None
if isinstance(type_spec, computation_types.FunctionType):
return computation_types.FunctionType(
_remove_struct_element_names_from_tff_type(type_spec.parameter),
_remove_struct_element_names_from_tff_type(type_spec.result))
if isinstance(type_spec, computation_types.TensorType):
return type_spec
py_typecheck.check_type(type_spec, computation_types.StructType)
return computation_types.StructType([
(None, _remove_struct_element_names_from_tff_type(v))
for _, v in structure.iter_elements(type_spec)
])
def _compute_summation_type_for_bitwidth(bitwidth, type_spec):
"""Creates a `tff.Type` with dtype based on bitwidth."""
def type_for_bitwidth_limited_tensor(bits, tensor_type):
if bits < 1 or bits > MAXIMUM_SUPPORTED_BITWIDTH:
raise ValueError(
'Encountered an bitwidth that cannot be handled: {b}. '
'Extended bitwidth must be between [1,{m}].'
'\nRequested: {r}'.format(b=bits,
r=bitwidth,
m=MAXIMUM_SUPPORTED_BITWIDTH))
elif bits < 32:
return computation_types.TensorType(
shape=tensor_type.shape,
dtype=tf.uint32 if tensor_type.dtype.is_unsigned else tf.int32)
else:
return computation_types.TensorType(
shape=tensor_type.shape,
dtype=tf.uint64 if tensor_type.dtype.is_unsigned else tf.int64)
if type_spec.is_tensor():
return type_for_bitwidth_limited_tensor(bitwidth, type_spec)
elif type_spec.is_struct():
return computation_types.StructType(
structure.iter_elements(
structure.map_structure(type_for_bitwidth_limited_tensor,
bitwidth, type_spec)))
else:
raise TypeError(
'Summation types can only be created from TensorType or '
'StructType. Received a {t}'.format(t=type_spec))
def is_sum_compatible(type_spec: computation_types.Type) -> bool:
"""Determines if `type_spec` is a type that can be added to itself.
Types that are sum-compatible are composed of scalars of numeric types,
possibly packaged into nested named tuples, and possibly federated. Types
that are sum-incompatible include sequences, functions, abstract types,
and placements.
Args:
type_spec: A `computation_types.Type`.
Returns:
`True` iff `type_spec` is sum-compatible, `False` otherwise.
"""
py_typecheck.check_type(type_spec, computation_types.Type)
if type_spec.is_tensor():
return is_numeric_dtype(
type_spec.dtype) and type_spec.shape.is_fully_defined()
elif type_spec.is_struct():
return all(
is_sum_compatible(v)
for _, v in structure.iter_elements(type_spec))
elif type_spec.is_federated():
return is_sum_compatible(type_spec.member)
else:
return False
def test_namedtuple_elements_two_tuples(self):
elems = [tf.int32 for k in range(10)]
t = computation_types.to_type(elems)
self.assertIsInstance(t, computation_types.StructWithPythonType)
self.assertIs(t.python_container, list)
for k in structure.iter_elements(t):
self.assertLen(k, 2)
async def compute(self):
"""Returns the result of computing the embedded value.
Raises:
TypeError: If the embedded value is composed of values that are not
embedded in the executor.
RuntimeError: If the embedded value is not a kind supported by the
`FederatingExecutor`.
"""
if isinstance(self._value, executor_value_base.ExecutorValue):
return await self._value.compute()
elif isinstance(self._value, structure.Struct):
results = await asyncio.gather(*[
FederatedResolvingStrategyValue(v, t).compute()
for v, t in zip(self._value, self._type_signature)
])
element_types = structure.iter_elements(self._type_signature)
return structure.Struct(
(n, v) for (n, _), v in zip(element_types, results))
elif isinstance(self._value, list):
py_typecheck.check_type(self._type_signature,
computation_types.FederatedType)
for value in self._value:
py_typecheck.check_type(value, executor_value_base.ExecutorValue)
if self._type_signature.all_equal:
return await self._value[0].compute()
else:
return await asyncio.gather(*[v.compute() for v in self._value])
else:
raise RuntimeError(
'Computing values of type {} represented as {} is not supported in '
'this executor.'.format(self._type_signature,
py_typecheck.type_string(type(self._value))))
def _unwrap(value):
if isinstance(value, tf.Tensor):
return value.numpy()
elif isinstance(value, structure.Struct):
return structure.Struct(
(k, _unwrap(v)) for k, v in structure.iter_elements(value))
else:
return value
def _pack_into_type(to_pack, type_spec):
"""Pack Tensor value `to_pack` into the nested structure `type_spec`."""
if type_spec.is_struct():
elem_iter = structure.iter_elements(type_spec)
return structure.Struct([(elem_name, _pack_into_type(to_pack, elem_type))
for elem_name, elem_type in elem_iter])
elif type_spec.is_tensor():
return tf.broadcast_to(to_pack, type_spec.shape)
def _unwrap_tensors(self, value):
if tf.is_tensor(value):
return value.numpy()
elif isinstance(value, structure.Struct):
return structure.Struct((k, self._unwrap_tensors(v))
for k, v in structure.iter_elements(value))
else:
return value
def _build(comp, scope):
"""Transforms `comp` to CDF, possibly adding bindings to `scope`."""
# The structure returned by this function is a generalized version of
# call-dominant form. This function may result in the patterns specified in
# the top-level function's docstring.
if comp.is_reference():
return scope.resolve(comp.name)
elif comp.is_selection():
source = _build(comp.source, scope)
if source.is_struct():
return source[comp.as_index()]
return building_blocks.Selection(source, index=comp.as_index())
elif comp.is_struct():
elements = []
for (name, value) in structure.iter_elements(comp):
value = _build(value, scope)
elements.append((name, value))
return building_blocks.Struct(elements)
elif comp.is_call():
function = _build(comp.function, scope)
argument = None if comp.argument is None else _build(
comp.argument, scope)
if function.is_lambda():
if argument is not None:
scope = scope.new_child()
scope.add_local(function.parameter_name, argument)
return _build(function.result, scope)
else:
return scope.create_binding(
building_blocks.Call(function, argument))
elif comp.is_lambda():
scope = scope.new_child_with_bindings()
if comp.parameter_name:
scope.add_local(
comp.parameter_name,
building_blocks.Reference(comp.parameter_name,
comp.parameter_type))
result = _build(comp.result, scope)
block = scope.bindings_to_block_with_result(result)
return building_blocks.Lambda(comp.parameter_name,
comp.parameter_type, block)
elif comp.is_block():
scope = scope.new_child()
for (name, value) in comp.locals:
scope.add_local(name, _build(value, scope))
return _build(comp.result, scope)
elif (comp.is_intrinsic() or comp.is_data()
or comp.is_compiled_computation()):
_disallow_higher_order(comp, global_comp)
return comp
elif comp.is_placement():
raise ValueError(
f'Found placement {comp} in\n{global_comp}\n'
'but placements are not allowed in local computations.')
else:
raise ValueError(
f'Unrecognized computation kind\n{comp}\nin\n{global_comp}')
def _create_result_tensor(type_spec, value):
"""Packs `value` into `type_spec` recursively."""
if type_spec.is_tensor():
type_spec.shape.assert_is_fully_defined()
result = tf.constant(value, dtype=type_spec.dtype, shape=type_spec.shape)
else:
elements = []
if inferred_value_type.is_struct():
# Copy the leaf values according to the type_spec structure.
for (name, elem_type), value in zip(
structure.iter_elements(type_spec), value):
elements.append((name, _create_result_tensor(elem_type, value)))
else:
# "Broadcast" the value to each level of the type_spec structure.
for _, elem_type in structure.iter_elements(type_spec):
elements.append((None, _create_result_tensor(elem_type, value)))
result = structure.Struct(elements)
return result
def _format_struct_type_members(struct_type: 'StructType') -> str:
def _element_repr(element):
name, value = element
if name is not None:
return '(\'{}\', {!r})'.format(name, value)
return repr(value)
return ', '.join(
_element_repr(e) for e in structure.iter_elements(struct_type))
def _deserialize_type_spec(serialize_type_variable, python_container=None):
"""Deserialize a `tff.Type` protocol buffer into a python class instance."""
type_spec = type_serialization.deserialize_type(
computation_pb2.Type.FromString(
serialize_type_variable.read_value().numpy()))
if type_spec.is_struct() and python_container is not None:
type_spec = computation_types.StructWithPythonType(
structure.iter_elements(type_spec), python_container)
return type_conversions.type_to_tf_structure(type_spec)
def update_state(structure, **kwargs):
"""Constructs a new `structure` with new values for fields in `kwargs`.
This is a helper method for working structured objects in a functional manner.
This method will create a new structure where the fields named by keys in
`kwargs` replaced with the associated values.
NOTE: This method only works on the first level of `structure`, and does not
recurse in the case of nested structures. A field that is itself a structure
can be replaced with another structure.
Args:
structure: The structure with named fields to update.
**kwargs: The list of key-value pairs of fields to update in `structure`.
Returns:
A new instance of the same type of `structure`, with the fields named
in the keys of `**kwargs` replaced with the associated values.
Raises:
KeyError: If kwargs contains a field that is not in structure.
TypeError: If structure is not a structure with named fields.
"""
if not (py_typecheck.is_named_tuple(structure)
or py_typecheck.is_attrs(structure)
or isinstance(structure,
(struct_lib.Struct, collections.abc.Mapping))):
raise TypeError(
'`structure` must be a structure with named fields (e.g. '
'dict, attrs class, collections.namedtuple, '
'tff.structure.Struct), but found {}'.format(type(structure)))
if isinstance(structure, struct_lib.Struct):
elements = [(k, v) if k not in kwargs else (k, kwargs.pop(k))
for k, v in struct_lib.iter_elements(structure)]
if kwargs:
raise KeyError(
f'`structure` does not contain fields named {kwargs}')
return struct_lib.Struct(elements)
elif py_typecheck.is_named_tuple(structure):
# In Python 3.8 and later `_asdict` no longer return OrdereDict, rather a
# regular `dict`, so we wrap here to get consistent types across Python
# version.s
d = collections.OrderedDict(structure._asdict())
elif py_typecheck.is_attrs(structure):
d = attr.asdict(structure, dict_factory=collections.OrderedDict)
else:
for key in kwargs:
if key not in structure:
raise KeyError(
'structure does not contain a field named "{!s}"'.format(
key))
d = structure
d.update(kwargs)
if isinstance(structure, collections.abc.Mapping):
return d
return type(structure)(**d)
def _partition_value(
val: _PartitioningValue,
type_signature: computation_types.Type) -> _PartitioningValue:
"""Partitions value as specified in _split_value_into_subrounds."""
if type_signature.is_struct():
struct_val = structure.from_container(val.payload)
result_container = []
for (_, val_elem), (name, type_elem) in zip(
structure.iter_elements(struct_val),
structure.iter_elements(type_signature)):
partitioning_val_elem = _PartitioningValue(
val_elem, val.num_remaining_clients,
val.num_remaining_partitions, val.last_client_index)
partition_result = _partition_value(partitioning_val_elem,
type_elem)
result_container.append((name, partition_result.payload))
return _PartitioningValue(structure.Struct(result_container),
partition_result.num_remaining_clients,
partition_result.num_remaining_partitions,
partition_result.last_client_index)
elif (type_signature.is_federated()
and type_signature.placement.is_clients()):
if type_signature.all_equal:
# In this case we simply replicate the argument for every subround.
return val
py_typecheck.check_type(val.payload, Sequence)
num_clients_for_subround = math.ceil(val.num_remaining_clients /
val.num_remaining_partitions)
num_remaining_clients = val.num_remaining_clients - num_clients_for_subround
num_remaining_partitions = val.num_remaining_partitions - 1
values_to_return = val.payload[val.last_client_index:val.
last_client_index +
num_clients_for_subround]
last_client_index = val.last_client_index + num_clients_for_subround
return _PartitioningValue(
payload=values_to_return,
num_remaining_clients=num_remaining_clients,
num_remaining_partitions=num_remaining_partitions,
last_client_index=last_client_index)
else:
return val
def _unwrap_execution_context_value(val):
"""Recursively removes wrapping from `val` under anonymous tuples."""
if isinstance(val, structure.Struct):
value_elements_iter = structure.iter_elements(val)
return structure.Struct((name, _unwrap_execution_context_value(elem))
for name, elem in value_elements_iter)
elif isinstance(val, ExecutionContextValue):
return _unwrap_execution_context_value(val.value)
else:
return val
async def _delegate(val, type_spec: computation_types.Type,
target_executor: executor_base.Executor):
"""Delegates value representation to target executor.
Args:
val: A value representation to delegate.
type_spec: The TFF type.
target_executor: The target executor to delegate.
Returns:
An instance of `executor_value_base.ExecutorValue` owned by the target
executor.
"""
py_typecheck.check_type(target_executor, executor_base.Executor)
if val is None:
return None
if isinstance(val, executor_value_base.ExecutorValue):
return val
if isinstance(val, _Sequence):
return await target_executor.create_value(await val.compute(),
type_spec)
if isinstance(val, structure.Struct):
if len(val) != len(type_spec):
raise ValueError(
'Found {} elements and {} types in a struct {}.'.format(
len(val), len(type_spec), str(val)))
elements = structure.iter_elements(val)
element_types = structure.iter_elements(type_spec)
names = []
coros = []
for (el_name, el), (el_type_name,
el_type) in zip(elements, element_types):
if el_name != el_type_name:
raise ValueError(
'Element name mismatch between value ({}) and type ({}).'.
format(str(val), str(type_spec)))
names.append(el_name)
coros.append(_delegate(el, el_type, target_executor))
flat_targets = await asyncio.gather(*coros)
reassembled_struct = structure.Struct(list(zip(names, flat_targets)))
return await target_executor.create_struct(reassembled_struct)
return await target_executor.create_value(val, type_spec)
def _check_or_get_unbound_abstract_type_labels(type_spec, bound_labels,
check):
"""Checks or collects abstract type labels from 'type_spec'.
This is a helper function used by 'check_abstract_types_are_bound', not to
be exported out of this module.
Args:
type_spec: An instance of computation_types.Type.
bound_labels: A set of string labels that refer to 'bound' abstract types,
i.e., ones that appear on the parameter side of a functional type.
check: A bool value. If True, no new unbound type labels are permitted,
and if False, any new labels encountered are returned as a set.
Returns:
If check is False, a set of new abstract type labels introduced in
'type_spec' that don't yet appear in the set 'bound_labels'. If check is
True, always returns an empty set.
Raises:
TypeError: if unbound labels are found and check is True.
"""
py_typecheck.check_type(type_spec, computation_types.Type)
if type_spec.is_tensor():
return set()
elif type_spec.is_sequence():
return _check_or_get_unbound_abstract_type_labels(
type_spec.element, bound_labels, check)
elif type_spec.is_federated():
return _check_or_get_unbound_abstract_type_labels(
type_spec.member, bound_labels, check)
elif type_spec.is_struct():
return set().union(*[
_check_or_get_unbound_abstract_type_labels(
v, bound_labels, check)
for _, v in structure.iter_elements(type_spec)
])
elif type_spec.is_abstract():
if type_spec.label in bound_labels:
return set()
elif not check:
return set([type_spec.label])
else:
raise TypeError('Unbound type label \'{}\'.'.format(
type_spec.label))
elif type_spec.is_function():
if type_spec.parameter is None:
parameter_labels = set()
else:
parameter_labels = _check_or_get_unbound_abstract_type_labels(
type_spec.parameter, bound_labels, False)
result_labels = _check_or_get_unbound_abstract_type_labels(
type_spec.result, bound_labels.union(parameter_labels), check)
return parameter_labels.union(result_labels)