Make SavedModel loading forward compatible by removing default attributes from the graph def that were not present in the consumer (server).

PiperOrigin-RevId: 172051437

7 files changed, 2769 insertions, 2 deletions

diff --git a/tensorflow/cc/saved_model/BUILD b/tensorflow/cc/saved_model/BUILD
index 1cc7cf3f20..e43ff91c60 100644
--- a/tensorflow/cc/saved_model/BUILD
+++ b/tensorflow/cc/saved_model/BUILD
@@ -54,6 +54,7 @@ cc_library(
     hdrs = ["loader.h"],
     deps = [
         ":constants",
+        "//tensorflow/core:framework",
     ] + if_not_mobile([
         "//tensorflow/core:core_cpu",
         "//tensorflow/core:lib",
@@ -88,6 +89,7 @@ tf_cc_test(
 filegroup(
     name = "saved_model_half_plus_two",
     srcs = glob([
+        "testdata/half_plus_two_forward_compatibility/**",
         "testdata/half_plus_two_pbtxt/**",
         "testdata/half_plus_two_main_op/**",
         "testdata/half_plus_two/**",
diff --git a/tensorflow/cc/saved_model/loader.cc b/tensorflow/cc/saved_model/loader.cc
index f98abc8a81..462308a48f 100644
--- a/tensorflow/cc/saved_model/loader.cc
+++ b/tensorflow/cc/saved_model/loader.cc
@@ -18,6 +18,7 @@ limitations under the License.
 #include <unordered_set>
 
 #include "tensorflow/cc/saved_model/constants.h"
+#include "tensorflow/core/framework/graph_def_util.h"
 #include "tensorflow/core/lib/io/path.h"
 #include "tensorflow/core/lib/monitoring/counter.h"
 #include "tensorflow/core/lib/strings/strcat.h"
@@ -224,6 +225,18 @@ Status GetAssetFileDefs(const MetaGraphDef& meta_graph_def,
   return Status::OK();
 }
 
+// For forward compatibility, remove new default attributes from the graph def
+// that were not present in the consumer (e.g. If graph was exported using
+// code that's newer than the server and a new default attr was added).
+Status RemoveNewDefaultAttrsFromMetaGraphDef(MetaGraphDef* meta_graph_def) {
+  OpListOpRegistry producer_op_registry(
+      &meta_graph_def->meta_info_def().stripped_op_list());
+  OpRegistry* consumer_op_registry = OpRegistry::Global();
+  return RemoveNewDefaultAttrsFromGraphDef(meta_graph_def->mutable_graph_def(),
+                                           *consumer_op_registry,
+                                           producer_op_registry, nullptr);
+}
+
 Status LoadSavedModelInternal(const SessionOptions& session_options,
                               const RunOptions& run_options,
                               const string& export_dir,
@@ -241,6 +254,9 @@ Status LoadSavedModelInternal(const SessionOptions& session_options,
   TF_RETURN_IF_ERROR(
       FindMetaGraphDefToLoad(saved_model_proto, tags, &bundle->meta_graph_def));
 
+  TF_RETURN_IF_ERROR(
+      RemoveNewDefaultAttrsFromMetaGraphDef(&bundle->meta_graph_def));
+
   TF_RETURN_IF_ERROR(LoadMetaGraphIntoSession(
       bundle->meta_graph_def, session_options, &bundle->session));
 
diff --git a/tensorflow/cc/saved_model/loader_test.cc b/tensorflow/cc/saved_model/loader_test.cc
index 0ad6b33bba..6dd14837b5 100644
--- a/tensorflow/cc/saved_model/loader_test.cc
+++ b/tensorflow/cc/saved_model/loader_test.cc
@@ -29,10 +29,12 @@ limitations under the License.
 namespace tensorflow {
 namespace {
 
-constexpr char kTestDataPbTxt[] =
-    "cc/saved_model/testdata/half_plus_two_pbtxt/00000123";
+constexpr char kTestDataForwardCompatibility[] =
+    "cc/saved_model/testdata/half_plus_two_forward_compatibility/00000123";
 constexpr char kTestDataMainOp[] =
     "cc/saved_model/testdata/half_plus_two_main_op/00000123";
+constexpr char kTestDataPbTxt[] =
+    "cc/saved_model/testdata/half_plus_two_pbtxt/00000123";
 constexpr char kTestDataSharded[] =
     "cc/saved_model/testdata/half_plus_two/00000123";
 
@@ -167,6 +169,24 @@ TEST_F(LoaderTest, PbtxtFormat) {
   CheckSavedModelBundle(export_dir, bundle);
 }
 
+// Forward compatibility graph has a new attr with a default value equal to the
+// value used by the server. If we handle new default attrs correctly, this test
+// will pass. This simulates adding new atts to the training code while server
+// code lags behind.
+TEST_F(LoaderTest, ForwardCompatibility) {
+  SavedModelBundle bundle;
+  SessionOptions session_options;
+  RunOptions run_options;
+
+  // TODO(b/67753689): Add support for regenerating this model in the export
+  // code.
+  const string export_dir =
+      io::JoinPath(testing::TensorFlowSrcRoot(), kTestDataForwardCompatibility);
+  TF_ASSERT_OK(LoadSavedModel(session_options, run_options, export_dir,
+                              {kSavedModelTagServe}, &bundle));
+  CheckSavedModelBundle(export_dir, bundle);
+}
+
 TEST_F(LoaderTest, MainOpFormat) {
   SavedModelBundle bundle;
   SessionOptions session_options;
diff --git a/tensorflow/cc/saved_model/testdata/half_plus_two_forward_compatibility/00000123/assets/foo.txt b/tensorflow/cc/saved_model/testdata/half_plus_two_forward_compatibility/00000123/assets/foo.txt
new file mode 100644
index 0000000000..f9ff036688
--- /dev/null
+++ b/tensorflow/cc/saved_model/testdata/half_plus_two_forward_compatibility/00000123/assets/foo.txt
@@ -0,0 +1 @@
+asset-file-contents
\ No newline at end of file
diff --git a/tensorflow/cc/saved_model/testdata/half_plus_two_forward_compatibility/00000123/saved_model.pbtxt b/tensorflow/cc/saved_model/testdata/half_plus_two_forward_compatibility/00000123/saved_model.pbtxt
new file mode 100755
index 0000000000..e799b3579c
--- /dev/null
+++ b/tensorflow/cc/saved_model/testdata/half_plus_two_forward_compatibility/00000123/saved_model.pbtxt
@@ -0,0 +1,2728 @@
+saved_model_schema_version: 1
+meta_graphs {
+  meta_info_def {
+    stripped_op_list {
+      op {
+        name: "Add"
+        input_arg {
+          name: "x"
+          type_attr: "T"
+        }
+        input_arg {
+          name: "y"
+          type_attr: "T"
+        }
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+              type: DT_FLOAT
+              type: DT_DOUBLE
+              type: DT_UINT8
+              type: DT_INT8
+              type: DT_INT16
+              type: DT_INT32
+              type: DT_INT64
+              type: DT_COMPLEX64
+              type: DT_COMPLEX128
+              type: DT_STRING
+            }
+          }
+        }
+      }
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+        name: "Assign"
+        input_arg {
+          name: "ref"
+          type_attr: "T"
+          is_ref: true
+        }
+        input_arg {
+          name: "value"
+          type_attr: "T"
+        }
+        output_arg {
+          name: "output_ref"
+          type_attr: "T"
+          is_ref: true
+        }
+        attr {
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+          type: "type"
+        }
+        attr {
+          name: "validate_shape"
+          type: "bool"
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+          }
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+          type: "bool"
+          default_value {
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+          }
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+      }
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diff --git a/tensorflow/cc/saved_model/testdata/half_plus_two_forward_compatibility/00000123/variables/variables.data-00000-of-00001 b/tensorflow/cc/saved_model/testdata/half_plus_two_forward_compatibility/00000123/variables/variables.data-00000-of-00001
new file mode 100755
index 0000000000..15b75d6ef6
--- /dev/null
+++ b/tensorflow/cc/saved_model/testdata/half_plus_two_forward_compatibility/00000123/variables/variables.data-00000-of-00001
diff --git a/tensorflow/cc/saved_model/testdata/half_plus_two_forward_compatibility/00000123/variables/variables.index b/tensorflow/cc/saved_model/testdata/half_plus_two_forward_compatibility/00000123/variables/variables.index
new file mode 100755
index 0000000000..7ec9fb4fe2
--- /dev/null
+++ b/tensorflow/cc/saved_model/testdata/half_plus_two_forward_compatibility/00000123/variables/variables.index