Preparation for switch in Keras serialization format (#834)

keras_tuner/engine/conditions.py

@@ -17,7 +17,6 @@
 import abc
 
 import six
-from tensorflow import keras
 
 from keras_tuner import utils
 from keras_tuner.protos import keras_tuner_pb2
@@ -145,8 +144,8 @@ def to_proto(self):
 
 
 def deserialize(config):
-    return keras.utils.deserialize_keras_object(config, module_objects=ALL_CLASSES)
+    return utils.deserialize_keras_object(config, module_objects=ALL_CLASSES)
 
 
 def serialize(obj):
-    return keras.utils.serialize_keras_object(obj)
+    return utils.serialize_keras_object(obj)

keras_tuner/engine/hyperparameters/__init__.py

@@ -14,6 +14,7 @@
 
 from tensorflow import keras
 
+from keras_tuner import utils
 from keras_tuner.engine.hyperparameters import hp_types
 from keras_tuner.engine.hyperparameters.hp_types import Boolean
 from keras_tuner.engine.hyperparameters.hp_types import Choice
@@ -32,8 +33,8 @@
 
 
 def deserialize(config):
-    return keras.utils.deserialize_keras_object(config, module_objects=ALL_CLASSES)
+    return utils.deserialize_keras_object(config, module_objects=ALL_CLASSES)
 
 
 def serialize(obj):
-    return keras.utils.serialize_keras_object(obj)
+    return utils.serialize_keras_object(obj)

keras_tuner/engine/hyperparameters/hp_types/__init__.py

@@ -14,6 +14,7 @@
 
 from tensorflow import keras
 
+from keras_tuner import utils
 from keras_tuner.engine.hyperparameters.hp_types.boolean_hp import Boolean
 from keras_tuner.engine.hyperparameters.hp_types.choice_hp import Choice
 from keras_tuner.engine.hyperparameters.hp_types.fixed_hp import Fixed
@@ -32,8 +33,8 @@
 
 
 def deserialize(config):
-    return keras.utils.deserialize_keras_object(config, module_objects=ALL_CLASSES)
+    return utils.deserialize_keras_object(config, module_objects=ALL_CLASSES)
 
 
 def serialize(obj):
-    return keras.utils.serialize_keras_object(obj)
+    return utils.serialize_keras_object(obj)

keras_tuner/engine/metrics_tracking.py

@@ -12,6 +12,7 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
+import inspect
 
 import numpy as np
 import six
@@ -332,10 +333,26 @@ def infer_metric_direction(metric):
             return "max"
 
         try:
-            metric = keras.metrics.get(metric_name)
+            if (
+                "use_legacy_format"
+                in inspect.getargspec(keras.metrics.deserialize).args
+            ):
+                metric = keras.metrics.deserialize(
+                    metric_name, use_legacy_format=True
+                )
+            else:
+                metric = keras.metrics.deserialize(metric_name)
         except ValueError:
             try:
-                metric = keras.losses.get(metric_name)
+                if (
+                    "use_legacy_format"
+                    in inspect.getargspec(keras.losses.deserialize).args
+                ):
+                    metric = keras.losses.deserialize(
+                        metric_name, use_legacy_format=True
+                    )
+                else:
+                    metric = keras.losses.deserialize(metric_name)
             except Exception:
                 # Direction can't be inferred.
                 return None

keras_tuner/utils.py

@@ -64,6 +64,24 @@ def check_tf_version():
         )
 
 
+def serialize_keras_object(obj):
+    if hasattr(tf.keras.utils, "legacy"):
+        return tf.keras.utils.legacy.serialize_keras_object(obj)
+    else:
+        return tf.keras.utils.serialize_keras_object(obj)
+
+
+def deserialize_keras_object(config, module_objects=None, custom_objects=None):
+    if hasattr(tf.keras.utils, "legacy"):
+        return tf.keras.utils.legacy.deserialize_keras_object(
+            config, custom_objects, module_objects
+        )
+    else:
+        return tf.keras.utils.deserialize_keras_object(
+            config, custom_objects, module_objects
+        )
+
+
 def to_list(values):
     if isinstance(values, list):
         return values