def load(export_dir, tags=None):
"""Load a SavedModel from `export_dir`.
Signatures associated with the SavedModel are available as functions:
```python
imported = tf.saved_model.load(path)
f = imported.signatures["serving_default"]
print(f(x=tf.constant([[1.]])))
```
Objects exported with `tf.saved_model.save` additionally have trackable
objects and functions assigned to attributes:
```python
exported = tf.train.Checkpoint(v=tf.Variable(3.))
exported.f = tf.function(
lambda x: exported.v * x,
input_signature=[tf.TensorSpec(shape=None, dtype=tf.float32)])
tf.saved_model.save(exported, path)
imported = tf.saved_model.load(path)
assert 3. == imported.v.numpy()
assert 6. == imported.f(x=tf.constant(2.)).numpy()
```
Args:
export_dir: The SavedModel directory to load from.
tags: A tag or sequence of tags identifying the MetaGraph to load. Optional
if the SavedModel contains a single MetaGraph, as for those exported from
`tf.saved_model.load`.
Returns:
A trackable object with a `signatures` attribute mapping from signature
keys to functions. If the SavedModel was exported by `tf.saved_model.load`,
it also points to trackable objects and functions which were attached
to the exported object.
Raises:
ValueError: If `tags` don't match a MetaGraph in the SavedModel.
"""
if tags is not None and not isinstance(tags, set):
# Supports e.g. tags=SERVING and tags=[SERVING]. Sets aren't considered
# sequences for nest.flatten, so we put those through as-is.
tags = nest.flatten(tags)
saved_model_proto = loader_impl.parse_saved_model(export_dir)
if (len(saved_model_proto.meta_graphs) == 1
and saved_model_proto.meta_graphs[0].HasField("object_graph_def")):
meta_graph_def = saved_model_proto.meta_graphs[0]
if (tags is not None
and set(tags) != set(meta_graph_def.meta_info_def.tags)):
raise ValueError(
("The SavedModel at {} has one MetaGraph with tags {}, but got an "
"incompatible argument tags={} to tf.saved_model.load. You may omit "
"it, pass 'None', or pass matching tags.")
.format(export_dir, meta_graph_def.meta_info_def.tags, tags))
object_graph_proto = meta_graph_def.object_graph_def
with ops.init_scope():
loader = _Loader(object_graph_proto,
saved_model_proto,
export_dir)
root = loader.get(0)
else:
with ops.init_scope():
root = load_v1_in_v2.load(export_dir, tags)
return root
def load(export_dir, tags=None):
"""Load a SavedModel from `export_dir`.
Signatures associated with the SavedModel are available as functions:
```python
imported = tf.saved_model.load(path)
f = imported.signatures["serving_default"]
print(f(x=tf.constant([[1.]])))
```
Objects exported with `tf.saved_model.save` additionally have trackable
objects and functions assigned to attributes:
```python
exported = tf.train.Checkpoint(v=tf.Variable(3.))
exported.f = tf.function(
lambda x: exported.v * x,
input_signature=[tf.TensorSpec(shape=None, dtype=tf.float32)])
tf.saved_model.save(exported, path)
imported = tf.saved_model.load(path)
assert 3. == imported.v.numpy()
assert 6. == imported.f(x=tf.constant(2.)).numpy()
```
_Importing SavedModels from TensorFlow 1.x_
SavedModels from `tf.estimator.Estimator` or 1.x SavedModel APIs have a flat
graph instead of `tf.function` objects. These SavedModels will have functions
corresponding to their signatures in the `.signatures` attribute, but also
have a `.prune` method which allows you to extract functions for new
subgraphs. This is equivalent to importing the SavedModel and naming feeds and
fetches in a Session from TensorFlow 1.x.
```python
imported = tf.saved_model.load(path_to_v1_saved_model)
pruned = imported.prune("x:0", "out:0")
pruned(tf.ones([]))
```
See `tf.compat.v1.wrap_function` for details. These SavedModels also have a
`.variables` attribute containing imported variables, and a `.graph` attribute
representing the whole imported graph. For SavedModels exported from
`tf.saved_model.save`, variables are instead assigned to whichever attributes
they were assigned before export.
Args:
export_dir: The SavedModel directory to load from.
tags: A tag or sequence of tags identifying the MetaGraph to load. Optional
if the SavedModel contains a single MetaGraph, as for those exported from
`tf.saved_model.load`.
Returns:
A trackable object with a `signatures` attribute mapping from signature
keys to functions. If the SavedModel was exported by `tf.saved_model.load`,
it also points to trackable objects and functions which were attached
to the exported object.
Raises:
ValueError: If `tags` don't match a MetaGraph in the SavedModel.
"""
if tags is not None and not isinstance(tags, set):
# Supports e.g. tags=SERVING and tags=[SERVING]. Sets aren't considered
# sequences for nest.flatten, so we put those through as-is.
tags = nest.flatten(tags)
saved_model_proto = loader_impl.parse_saved_model(export_dir)
if (len(saved_model_proto.meta_graphs) == 1
and saved_model_proto.meta_graphs[0].HasField("object_graph_def")):
meta_graph_def = saved_model_proto.meta_graphs[0]
if (tags is not None
and set(tags) != set(meta_graph_def.meta_info_def.tags)):
raise ValueError(
("The SavedModel at {} has one MetaGraph with tags {}, but got an "
"incompatible argument tags={} to tf.saved_model.load. You may omit "
"it, pass 'None', or pass matching tags.")
.format(export_dir, meta_graph_def.meta_info_def.tags, tags))
object_graph_proto = meta_graph_def.object_graph_def
with ops.init_scope():
loader = _Loader(object_graph_proto,
saved_model_proto,
export_dir)
root = loader.get(0)
root.tensorflow_version = meta_graph_def.meta_info_def.tensorflow_version
root.tensorflow_git_version = (
meta_graph_def.meta_info_def.tensorflow_git_version)
else:
with ops.init_scope():
root = load_v1_in_v2.load(export_dir, tags)
return root
def load_partial(export_dir, filters, tags=None, options=None):
"""Partially load a SavedModel (saved from V2).
Similar to `tf.saved_model.load`, but with an additional argument that
lets you specify which nodes to load.
`tf.saved_model.load_partial(export_dir, ["root"])` and
`tf.saved_model.load(export_dir)` are equivalent.
Note: This only works for SavedModels saved with TensorFlow V2 from
`tf.saved_model.save` or Keras. This will not load SavedModels save from
the Estimator API.
In Tensorflow V2, SavedModel stores the **object graph** of the saved object.
The graph contains nodes (`tf.Module`, `tf.Variable`, `tf.function`, Keras
layers, etc.) and edges that are the name of the attributes connecting the
objects.
*Example 1*
```
model = tf.Module()
model.child_layer = tf.Module()
model.child_layer.v = tf.Variable(5.)
tf.saved_model.save(model, '/tmp/model')
loaded = tf.__internal__.saved_model.load_partial(
... '/tmp/model',
... ['root.child_layer', 'root.child_layer.v'])
loaded['root.child_layer'].v.numpy()
5.
loaded['root.child_layer'].v is loaded['root.child_layer.v']
True
*Example 2*
model = tf.Module()
model.child_layer = tf.Module()
model.child_layer.v = tf.Variable(5.)
>>>
tf.saved_model.save(model, '/tmp/model')
# Create a variable
new_variable = tf.Variable(0.)
loaded = tf.__internal__.saved_model.load_partial(
... '/tmp/model',
... {'root.child_layer': None, 'root.child_layer.v': new_variable})
loaded['root.child_layer'].v.numpy()
5.
new_variable.numpy()
5.
```
**Loading under different distribution strategies**
You can load different parts of the model under different distribution
strategies. Note that this is very experimental so use with care.
```
model = tf.Module()
model.layer_1 = tf.Module()
model.layer_1.v = tf.Variable(5.)
model.layer_2 = tf.Module()
model.layer_2.v = tf.Variable(7.)
tf.saved_model.save(model, '/tmp/model')
# Load with no strategy
loaded = tf.__internal__.saved_model.load_partial(
... '/tmp/model',
... ['root.layer_1'])
loaded['root.layer_1'].v
<tf.Variable 'Variable:0' shape=() dtype=float32, numpy=5.0>
strategy = tf.distribute.MirroredStrategy()
with strategy.scope():
... loaded2 = tf.__internal__.saved_model.load_partial(
... '/tmp/model',
... ['root.layer_2'])
loaded2['root.layer_2'].v
MirroredVariable:{
0: <tf.Variable 'Variable:0' shape=() dtype=float32, numpy=7.0>
}
```
Args:
export_dir: The SavedModel directory to load from.
filters: A list or dictionary where each element or key is a string
path to nodes that should be loaded. Node paths consist of all the child
attribute names to reach that node in the form: `root.{attribute_name}`.
The loader will load all of the specified nodes and their recursive
descendants. When this option is defined, the loader will return a
dictionary mapping the node paths to the loaded objects.
tags: A tag or sequence of tags identifying the MetaGraph to load. Optional
if the SavedModel contains a single MetaGraph, as for those exported from
`tf.saved_model.save`.
options: `tf.saved_model.LoadOptions` object that specifies options for
loading.
Returns:
A dictionary mapping node paths from the filter to loaded objects.
"""
options = options or load_options.LoadOptions()
if tags is not None and not isinstance(tags, set):
# Supports e.g. tags=SERVING and tags=[SERVING]. Sets aren't considered
# sequences for nest.flatten, so we put those through as-is.
tags = nest.flatten(tags)
saved_model_proto, debug_info = (
loader_impl.parse_saved_model_with_debug_info(export_dir))
if (len(saved_model_proto.meta_graphs) == 1 and
saved_model_proto.meta_graphs[0].HasField("object_graph_def")):
metrics.IncrementReadApi(_LOAD_V2_LABEL)
meta_graph_def = saved_model_proto.meta_graphs[0]
# tensor_content field contains raw bytes in litle endian format
# which causes problems when loaded on big-endian systems
# requiring byteswap
if sys.byteorder == "big":
saved_model_utils.swap_function_tensor_content(meta_graph_def, "little",
"big")
if (tags is not None
and set(tags) != set(meta_graph_def.meta_info_def.tags)):
raise ValueError(
f"Got an incompatible argument to `tags`: {tags}. The SavedModel at "
f"{export_dir} has one MetaGraph with tags "
f"{meta_graph_def.meta_info_def.tags}. You may omit the argument, "
"pass 'None', or pass matching tags.")
object_graph_proto = meta_graph_def.object_graph_def
ckpt_options = checkpoint_options.CheckpointOptions(
experimental_io_device=options.experimental_io_device)
with ops.init_scope():
try:
loader = Loader(object_graph_proto, saved_model_proto, export_dir,
ckpt_options, options, filters)
except errors.NotFoundError as err:
raise FileNotFoundError(
str(err) + "\n You may be trying to load on a different device "
"from the computational device. Consider setting the "
"`experimental_io_device` option in `tf.saved_model.LoadOptions` "
"to the io_device such as '/job:localhost'.")
root = loader.get(0)
root.graph_debug_info = loader.adjust_debug_info_func_names(debug_info)
root.tensorflow_version = meta_graph_def.meta_info_def.tensorflow_version
root.tensorflow_git_version = (
meta_graph_def.meta_info_def.tensorflow_git_version)
metrics.IncrementRead(write_version="2")
else:
if filters:
raise ValueError("SavedModels saved from Tensorflow 1.x or Estimator (any"
" version) cannot be loaded with node filters.")
with ops.init_scope():
root = load_v1_in_v2.load(export_dir, tags)
root.graph_debug_info = debug_info
if filters:
return {node_id: loader.get(node_id) for node_id in filters}
else:
return {"root": root}
def load(export_dir, tags=None):
"""Load a SavedModel from `export_dir`.
Signatures associated with the SavedModel are available as functions:
```python
imported = tf.saved_model.load(path)
f = imported.signatures["serving_default"]
print(f(x=tf.constant([[1.]])))
```
Objects exported with `tf.saved_model.save` additionally have trackable
objects and functions assigned to attributes:
```python
exported = tf.train.Checkpoint(v=tf.Variable(3.))
exported.f = tf.function(
lambda x: exported.v * x,
input_signature=[tf.TensorSpec(shape=None, dtype=tf.float32)])
tf.saved_model.save(exported, path)
imported = tf.saved_model.load(path)
assert 3. == imported.v.numpy()
assert 6. == imported.f(x=tf.constant(2.)).numpy()
```
Args:
export_dir: The SavedModel directory to load from.
tags: A tag or sequence of tags identifying the MetaGraph to load. Optional
if the SavedModel contains a single MetaGraph, as for those exported from
`tf.saved_model.load`.
Returns:
A trackable object with a `signatures` attribute mapping from signature
keys to functions. If the SavedModel was exported by `tf.saved_model.load`,
it also points to trackable objects and functions which were attached
to the exported object.
Raises:
ValueError: If `tags` don't match a MetaGraph in the SavedModel.
"""
if tags is not None and not isinstance(tags, set):
# Supports e.g. tags=SERVING and tags=[SERVING]. Sets aren't considered
# sequences for nest.flatten, so we put those through as-is.
tags = nest.flatten(tags)
saved_model_proto = loader_impl.parse_saved_model(export_dir)
if (len(saved_model_proto.meta_graphs) == 1
and saved_model_proto.meta_graphs[0].HasField("object_graph_def")):
meta_graph_def = saved_model_proto.meta_graphs[0]
if (tags is not None
and set(tags) != set(meta_graph_def.meta_info_def.tags)):
raise ValueError((
"The SavedModel at {} has one MetaGraph with tags {}, but got an "
"incompatible argument tags={} to tf.saved_model.load. You may omit "
"it, pass 'None', or pass matching tags.").format(
export_dir, meta_graph_def.meta_info_def.tags, tags))
object_graph_proto = meta_graph_def.object_graph_def
with ops.init_scope():
loader = _Loader(object_graph_proto, saved_model_proto, export_dir)
root = loader.get(0)
else:
with ops.init_scope():
root = load_v1_in_v2.load(export_dir, tags)
return root
def load_tf_checkpoints(model, config, tf_checkpoint_path):
print("Building PyTorch model from configuration: {}".format(
str(config)))
print("Converting TensorFlow checkpoint from {}".format(
tf_checkpoint_path))
# Load weights from TF model
init_vars = load_v1_in_v2.load(tf_checkpoint_path, tags=["train"])
names = []
arrays = []
n_params = 0
for tf_var in init_vars.variables:
name = tf_var.name
print("Loading TF weight {} with shape {}".format(
name, tf_var.shape))
n_params += np.prod(tf_var.shape)
names.append(name)
arrays.append(tf_var.numpy())
for name, array in zip(names, arrays):
name = re.sub(r"module\/|\:0", "", name).strip()
name = name.split("/")
# adam_v and adam_m are variables used in AdamWeightDecayOptimizer to calculated m and v
# which are not required for using pretrained model
if any(n in [
"adam_v",
"adam_m",
"AdamWeightDecayOptimizer",
"AdamWeightDecayOptimizer_1",
"global_step",
] for n in name):
print("Skipping {}".format("/".join(name)))
continue
pointer = model
for m_name in name:
if re.fullmatch(r"[A-Za-z]+_\d+", m_name):
scope_names = re.split(r"_(\d+)", m_name)
else:
scope_names = [m_name]
if scope_names[0] == "kernel" or scope_names[0] == "gamma":
pointer = getattr(pointer, "weight")
elif scope_names[0] == "output_bias" or scope_names[
0] == "beta":
pointer = getattr(pointer, "bias")
elif scope_names[0] == "output_weights":
pointer = getattr(pointer, "weight")
elif scope_names[0] == "squad":
pointer = getattr(pointer, "classifier")
else:
try:
pointer = getattr(pointer, scope_names[0])
except AttributeError:
print("Skipping {}".format("/".join(name)))
continue
if len(scope_names) >= 2:
num = int(scope_names[1])
pointer = pointer[num]
if m_name[-11:] == "_embeddings":
pointer = getattr(pointer, "weight")
elif m_name == "kernel":
array = np.transpose(array)
try:
assert (
pointer.shape == array.shape
), f"Pointer shape {pointer.shape} and array shape {array.shape} mismatched"
except AssertionError as e:
e.args += (pointer.shape, array.shape)
raise
print("Initialize PyTorch weight {}".format(name))
pointer.data = torch.from_numpy(array)
return model
def load_internal(export_dir, tags=None, options=None, loader_cls=Loader,
filters=None):
"""Loader implementation."""
options = options or load_options.LoadOptions()
if tags is not None and not isinstance(tags, set):
# Supports e.g. tags=SERVING and tags=[SERVING]. Sets aren't considered
# sequences for nest.flatten, so we put those through as-is.
tags = nest.flatten(tags)
saved_model_proto, debug_info = (
loader_impl.parse_saved_model_with_debug_info(export_dir))
if (len(saved_model_proto.meta_graphs) == 1 and
saved_model_proto.meta_graphs[0].HasField("object_graph_def")):
metrics.IncrementReadApi(_LOAD_V2_LABEL)
meta_graph_def = saved_model_proto.meta_graphs[0]
# tensor_content field contains raw bytes in litle endian format
# which causes problems when loaded on big-endian systems
# requiring byteswap
if sys.byteorder == "big":
saved_model_utils.swap_function_tensor_content(meta_graph_def, "little",
"big")
if (tags is not None
and set(tags) != set(meta_graph_def.meta_info_def.tags)):
raise ValueError(
"Got an incompatible argument to `tags`: {tags}. The SavedModel at "
f"{export_dir} has one MetaGraph with tags "
f"{meta_graph_def.meta_info_def.tags}. You may omit the argument, "
"pass 'None', or pass matching tags.")
object_graph_proto = meta_graph_def.object_graph_def
ckpt_options = checkpoint_options.CheckpointOptions(
experimental_io_device=options.experimental_io_device)
with ops.init_scope():
try:
loader = loader_cls(object_graph_proto, saved_model_proto, export_dir,
ckpt_options, options, filters)
except errors.NotFoundError as err:
raise FileNotFoundError(
str(err) + "\n You may be trying to load on a different device "
"from the computational device. Consider setting the "
"`experimental_io_device` option in `tf.saved_model.LoadOptions` "
"to the io_device such as '/job:localhost'.")
root = loader.get(0)
if isinstance(loader, Loader):
root.graph_debug_info = loader.adjust_debug_info_func_names(debug_info)
root.tensorflow_version = meta_graph_def.meta_info_def.tensorflow_version
root.tensorflow_git_version = (
meta_graph_def.meta_info_def.tensorflow_git_version)
metrics.IncrementRead(write_version="2")
else:
if filters:
raise ValueError("SavedModels saved from Tensorflow 1.x or Estimator (any"
" version) cannot be loaded with node filters.")
with ops.init_scope():
root = load_v1_in_v2.load(export_dir, tags)
root.graph_debug_info = debug_info
if filters:
return {node_id: loader.get(node_id) for node_id in filters}
else:
return {"root": root}
def load(export_dir, tags=None):
"""Load a SavedModel from `export_dir`.
Signatures associated with the SavedModel are available as functions:
```python
imported = tf.saved_model.load(path)
f = imported.signatures["serving_default"]
print(f(x=tf.constant([[1.]])))
```
Objects exported with `tf.saved_model.save` additionally have trackable
objects and functions assigned to attributes:
```python
exported = tf.train.Checkpoint(v=tf.Variable(3.))
exported.f = tf.function(
lambda x: exported.v * x,
input_signature=[tf.TensorSpec(shape=None, dtype=tf.float32)])
tf.saved_model.save(exported, path)
imported = tf.saved_model.load(path)
assert 3. == imported.v.numpy()
assert 6. == imported.f(x=tf.constant(2.)).numpy()
```
_Importing SavedModels from TensorFlow 1.x_
SavedModels from `tf.estimator.Estimator` or 1.x SavedModel APIs have a flat
graph instead of `tf.function` objects. These SavedModels will have functions
corresponding to their signatures in the `.signatures` attribute, but also
have a `.prune` method which allows you to extract functions for new
subgraphs. This is equivalent to importing the SavedModel and naming feeds and
fetches in a Session from TensorFlow 1.x.
```python
imported = tf.saved_model.load(path_to_v1_saved_model)
pruned = imported.prune("x:0", "out:0")
pruned(tf.ones([]))
```
See `tf.compat.v1.wrap_function` for details. These SavedModels also have a
`.variables` attribute containing imported variables, and a `.graph` attribute
representing the whole imported graph. For SavedModels exported from
`tf.saved_model.save`, variables are instead assigned to whichever attributes
they were assigned before export.
Args:
export_dir: The SavedModel directory to load from.
tags: A tag or sequence of tags identifying the MetaGraph to load. Optional
if the SavedModel contains a single MetaGraph, as for those exported from
`tf.saved_model.load`.
Returns:
A trackable object with a `signatures` attribute mapping from signature
keys to functions. If the SavedModel was exported by `tf.saved_model.load`,
it also points to trackable objects and functions which were attached
to the exported object.
Raises:
ValueError: If `tags` don't match a MetaGraph in the SavedModel.
"""
if tags is not None and not isinstance(tags, set):
# Supports e.g. tags=SERVING and tags=[SERVING]. Sets aren't considered
# sequences for nest.flatten, so we put those through as-is.
tags = nest.flatten(tags)
saved_model_proto = loader_impl.parse_saved_model(export_dir)
if (len(saved_model_proto.meta_graphs) == 1
and saved_model_proto.meta_graphs[0].HasField("object_graph_def")):
meta_graph_def = saved_model_proto.meta_graphs[0]
if (tags is not None
and set(tags) != set(meta_graph_def.meta_info_def.tags)):
raise ValueError((
"The SavedModel at {} has one MetaGraph with tags {}, but got an "
"incompatible argument tags={} to tf.saved_model.load. You may omit "
"it, pass 'None', or pass matching tags.").format(
export_dir, meta_graph_def.meta_info_def.tags, tags))
object_graph_proto = meta_graph_def.object_graph_def
with ops.init_scope():
loader = _Loader(object_graph_proto, saved_model_proto, export_dir)
root = loader.get(0)
root.tensorflow_version = meta_graph_def.meta_info_def.tensorflow_version
root.tensorflow_git_version = (
meta_graph_def.meta_info_def.tensorflow_git_version)
else:
with ops.init_scope():
root = load_v1_in_v2.load(export_dir, tags)
return root
