1syntax = "proto3";
2
3import "tensorflow/core/protobuf/trackable_object_graph.proto";
4import "tensorflow/core/protobuf/struct.proto";
5import "tensorflow/core/framework/tensor_shape.proto";
6import "tensorflow/core/framework/types.proto";
7import "tensorflow/core/framework/versions.proto";
8
9option cc_enable_arenas = true;
10
11package tensorflow;
12
13// A SavedObjectGraph is part of object-based SavedModels in TF 2.0. It
14// describes the directed graph of Python objects (or equivalent in other
15// languages) that make up a model, with nodes[0] at the root.
16
17// SavedObjectGraph shares some structure with TrackableObjectGraph, but
18// SavedObjectGraph belongs to the MetaGraph and contains pointers to functions
19// and type information, while TrackableObjectGraph lives in the checkpoint
20// and contains pointers only to variable values.
21
22message SavedObjectGraph {
23  // Flattened list of objects in the object graph.
24  //
25  // The position of the object in this list indicates its id.
26  // Nodes[0] is considered the root node.
27  repeated SavedObject nodes = 1;
28
29  // Information about captures and output structures in concrete functions.
30  // Referenced from SavedBareConcreteFunction and SavedFunction.
31  map<string, SavedConcreteFunction> concrete_functions = 2;
32}
33
34message SavedObject {
35  // Objects which this object depends on: named edges in the dependency
36  // graph.
37  //
38  // Note: currently only valid if kind == "user_object".
39  repeated TrackableObjectGraph.TrackableObject.ObjectReference
40      children = 1;
41
42  // Removed when forking SavedObject from TrackableObjectGraph.
43  reserved "attributes";
44  reserved 2;
45
46  // Slot variables owned by this object. This describes the three-way
47  // (optimizer, variable, slot variable) relationship; none of the three
48  // depend on the others directly.
49  //
50  // Note: currently only valid if kind == "user_object".
51  repeated TrackableObjectGraph.TrackableObject.SlotVariableReference
52      slot_variables = 3;
53
54  oneof kind {
55    SavedUserObject user_object = 4;
56    SavedAsset asset = 5;
57    SavedFunction function = 6;
58    SavedVariable variable = 7;
59    SavedBareConcreteFunction bare_concrete_function = 8;
60    SavedConstant constant = 9;
61    SavedResource resource = 10;
62  }
63}
64
65// A SavedUserObject is an object (in the object-oriented language of the
66// TensorFlow program) of some user- or framework-defined class other than
67// those handled specifically by the other kinds of SavedObjects.
68//
69// This object cannot be evaluated as a tensor, and therefore cannot be bound
70// to an input of a function.
71message SavedUserObject {
72  // Corresponds to a registration of the type to use in the loading program.
73  string identifier = 1;
74  // Version information from the producer of this SavedUserObject.
75  VersionDef version = 2;
76}
77
78// A SavedAsset points to an asset in the MetaGraph.
79//
80// When bound to a function this object evaluates to a tensor with the absolute
81// filename. Users should not depend on a particular part of the filename to
82// remain stable (e.g. basename could be changed).
83message SavedAsset {
84  // Index into `MetaGraphDef.asset_file_def[]` that describes the Asset.
85  //
86  // Only the field `AssetFileDef.filename` is used. Other fields, such as
87  // `AssetFileDef.tensor_info`, MUST be ignored.
88  int32 asset_file_def_index = 1;
89}
90
91// A function with multiple signatures, possibly with non-Tensor arguments.
92message SavedFunction {
93  repeated string concrete_functions = 1;
94  FunctionSpec function_spec = 2;
95}
96
97// Stores low-level information about a concrete function. Referenced in either
98// a SavedFunction or a SavedBareConcreteFunction.
99message SavedConcreteFunction {
100  // Bound inputs to the function. The SavedObjects identified by the node ids
101  // given here are appended as extra inputs to the caller-supplied inputs.
102  // The only types of SavedObjects valid here are SavedVariable, SavedResource
103  // and SavedAsset.
104  repeated int32 bound_inputs = 2;
105  // Input in canonicalized form that was received to create this concrete
106  // function.
107  StructuredValue canonicalized_input_signature = 3;
108  // Output that was the return value of this function after replacing all
109  // Tensors with TensorSpecs. This can be an arbitrary nested function and will
110  // be used to reconstruct the full structure from pure tensors.
111  StructuredValue output_signature = 4;
112}
113
114message SavedBareConcreteFunction {
115  // Identifies a SavedConcreteFunction.
116  string concrete_function_name = 1;
117
118  // A sequence of unique strings, one per Tensor argument.
119  repeated string argument_keywords = 2;
120  // The prefix of `argument_keywords` which may be identified by position.
121  int64 allowed_positional_arguments = 3;
122}
123
124message SavedConstant {
125  // An Operation name for a ConstantOp in this SavedObjectGraph's MetaGraph.
126  string operation = 1;
127}
128
129// Represents a Variable that is initialized by loading the contents from the
130// checkpoint.
131message SavedVariable {
132  DataType dtype = 1;
133  TensorShapeProto shape = 2;
134  bool trainable = 3;
135}
136
137// Represents `FunctionSpec` used in `Function`. This represents a
138// function that has been wrapped as a TensorFlow `Function`.
139message FunctionSpec {
140  // Full arg spec from inspect.getfullargspec().
141  StructuredValue fullargspec = 1;
142  // Whether this represents a class method.
143  bool is_method = 2;
144  // Which arguments to always prepend, in case the original function is based
145  // on a functools.partial.
146  StructuredValue args_to_prepend = 3;
147  // Which kwargs to always include, in case the original function is based on a
148  // functools.partial.
149  StructuredValue kwargs_to_include = 4;
150  // The input signature, if specified.
151  StructuredValue input_signature = 5;
152}
153
154// A SavedResource represents a TF object that holds state during its lifetime.
155message SavedResource {
156  // An object of this type can have a reference to a:
157  // create_resource() and an initialize() function.
158}
159