Go: Add a SavedModel type

Change: 147543652

4 files changed, 96 insertions, 50 deletions

diff --git a/tensorflow/go/saved_model.go b/tensorflow/go/saved_model.go
new file mode 100644
index 0000000000..9bffa61765
--- /dev/null
+++ b/tensorflow/go/saved_model.go
@@ -0,0 +1,68 @@
+// Copyright 2017 The TensorFlow Authors. All Rights Reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+package tensorflow
+
+import (
+	"runtime"
+	"unsafe"
+)
+
+// #include <stdlib.h>
+// #include "tensorflow/c/c_api.h"
+import "C"
+
+// SavedModel represents the contents of loaded SavedModel.
+// TODO(jhseu): Add and document metagraphdef when we pregenerate protobufs.
+type SavedModel struct {
+	Session *Session
+	Graph   *Graph
+}
+
+// LoadSavedModel creates a new SavedModel from a model previously
+// exported to a directory on disk.
+//
+// Exported models contain a set of graphs and, optionally, variable values.
+// Tags in the model identify a single graph. LoadSavedModel initializes a
+// session with the identified graph and with variables initialized to from the
+// checkpoints on disk.
+//
+// The tensorflow package currently does not have the ability to export a model
+// to a directory from Go. This function thus currently targets loading models
+// exported in other languages, such as using tf.saved_model.builder in Python.
+// See:
+// https://www.tensorflow.org/code/tensorflow/python/saved_model/
+func LoadSavedModel(exportDir string, tags []string, options *SessionOptions) (*SavedModel, error) {
+	status := newStatus()
+	cOpt := options.c()
+	cExportDir := C.CString(exportDir)
+	cTags := make([]*C.char, len(tags))
+	for i := range tags {
+		cTags[i] = C.CString(tags[i])
+	}
+	graph := NewGraph()
+	// TODO(jhseu): Add support for run_options and meta_graph_def.
+	cSess := C.TF_LoadSessionFromSavedModel(cOpt, nil, cExportDir, (**C.char)(unsafe.Pointer(&cTags[0])), C.int(len(cTags)), graph.c, nil, status.c)
+	for i := range cTags {
+		C.free(unsafe.Pointer(cTags[i]))
+	}
+	C.free(unsafe.Pointer(cExportDir))
+	C.TF_DeleteSessionOptions(cOpt)
+
+	if err := status.Err(); err != nil {
+		return nil, err
+	}
+	s := &Session{c: cSess}
+	runtime.SetFinalizer(s, func(s *Session) { s.Close() })
+	return &SavedModel{Session: s, Graph: graph}, nil
+}
diff --git a/tensorflow/go/saved_model_test.go b/tensorflow/go/saved_model_test.go
new file mode 100644
index 0000000000..685312ae8c
--- /dev/null
+++ b/tensorflow/go/saved_model_test.go
@@ -0,0 +1,28 @@
+// Copyright 2017 The TensorFlow Authors. All Rights Reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+package tensorflow
+
+import "testing"
+
+func TestSavedModel(t *testing.T) {
+	bundle, err := LoadSavedModel("../cc/saved_model/testdata/half_plus_two/00000123", []string{"serve"}, nil)
+	if err != nil {
+		t.Fatalf("LoadSavedModel(): %v", err)
+	}
+	if op := bundle.Graph.Operation("y"); op == nil {
+		t.Fatalf("\"y\" not found in graph")
+	}
+	// TODO(jhseu): half_plus_two has a tf.Example proto dependency to run. Add a
+	// more thorough test when the generated protobufs are available.
+}
diff --git a/tensorflow/go/session.go b/tensorflow/go/session.go
index c29b6e0b76..dd629441ef 100644
--- a/tensorflow/go/session.go
+++ b/tensorflow/go/session.go
@@ -59,44 +59,6 @@ func NewSession(graph *Graph, options *SessionOptions) (*Session, error) {
 	return s, nil
 }
 
-// LoadSavedModel creates a new Session from a model previously exported to a
-// directory on disk.
-//
-// Exported models contain a set of graphs and variable values. Tags in the
-// model identify a single graph. LoadSessionFromSavedModel initializes a
-// session with the identified graph and with variables initialized to saved
-// values.
-//
-// The tensorflow package currently does not have the ability to export a model
-// to a directory from Go. This function thus currently targets loading models
-// exported in other languages, such as using tf.saved_model.builder in Python.
-// See:
-// https://www.tensorflow.org/code/tensorflow/python/saved_model/
-func LoadSavedModel(exportDir string, tags []string, options *SessionOptions) (*Session, *Graph, error) {
-	status := newStatus()
-	cOpt := options.c()
-	cExportDir := C.CString(exportDir)
-	cTags := make([]*C.char, len(tags))
-	for i := range tags {
-		cTags[i] = C.CString(tags[i])
-	}
-	graph := NewGraph()
-	// TODO(jhseu): Add support for run_options and meta_graph_def.
-	cSess := C.TF_LoadSessionFromSavedModel(cOpt, nil, cExportDir, (**C.char)(unsafe.Pointer(&cTags[0])), C.int(len(cTags)), graph.c, nil, status.c)
-	for i := range cTags {
-		C.free(unsafe.Pointer(cTags[i]))
-	}
-	C.free(unsafe.Pointer(cExportDir))
-	C.TF_DeleteSessionOptions(cOpt)
-
-	if err := status.Err(); err != nil {
-		return nil, nil, err
-	}
-	s := &Session{c: cSess}
-	runtime.SetFinalizer(s, func(s *Session) { s.Close() })
-	return s, graph, nil
-}
-
 // Run the graph with the associated session starting with the supplied inputs.
 // inputs and outputs may be set to nil. Runs, but does not return Tensors
 // for operations specified in targets.
diff --git a/tensorflow/go/session_test.go b/tensorflow/go/session_test.go
index ccd7d85295..14ecca402b 100644
--- a/tensorflow/go/session_test.go
+++ b/tensorflow/go/session_test.go
@@ -181,15 +181,3 @@ func TestConcurrency(t *testing.T) {
 		t.Errorf("Close() 2: %v", err)
 	}
 }
-
-func TestSavedModel(t *testing.T) {
-	_, graph, err := LoadSavedModel("../cc/saved_model/testdata/half_plus_two/00000123", []string{"serve"}, nil)
-	if err != nil {
-		t.Fatalf("LoadSavedModel(): %v", err)
-	}
-	if op := graph.Operation("y"); op == nil {
-		t.Fatalf("\"y\" not found in graph")
-	}
-	// TODO(jhseu): half_plus_two has a tf.Example proto dependency to run. Add a
-	// more thorough test when the generated protobufs are available.
-}