Allows calling keras layers in eager mode.

PiperOrigin-RevId: 173129805

tensorflow/python/keras/_impl/keras/engine/topology.py

@@ -26,6 +26,7 @@ import os
 import numpy as np
 from six.moves import zip  # pylint: disable=redefined-builtin
 
+from tensorflow.python.eager import context
 from tensorflow.python.framework import tensor_shape
 from tensorflow.python.keras._impl.keras import backend as K
 from tensorflow.python.keras._impl.keras.utils import conv_utils
@@ -250,6 +251,8 @@ class Layer(tf_base_layers.Layer):
     """
     # Actually call the layer (optionally building it).
     output = super(Layer, self).__call__(inputs, **kwargs)
+    if context.in_eager_mode():
+      return output
 
     # Update learning phase info.
     output_tensors = _to_list(output)

tensorflow/python/keras/_impl/keras/layers/core_test.py

@@ -20,8 +20,11 @@ from __future__ import print_function
 
 import numpy as np
 
+from tensorflow.python.eager import context
+from tensorflow.python.framework import constant_op
 from tensorflow.python.keras._impl import keras
 from tensorflow.python.keras._impl.keras import testing_utils
+from tensorflow.python.ops import init_ops
 from tensorflow.python.platform import test
 
 
@@ -198,6 +201,12 @@ class CoreLayersTest(test.TestCase):
       self.assertEqual(layer.kernel.constraint, k_constraint)
       self.assertEqual(layer.bias.constraint, b_constraint)
 
+  def test_eager_dense(self):
+    with context.eager_mode():
+      l = keras.layers.Dense(units=3,
+                             kernel_initializer=init_ops.zeros_initializer())
+      self.assertAllEqual(l(constant_op.constant([[1.0]])), [[0., 0., 0.]])
+
   def test_activity_regularization(self):
     with self.test_session():
       layer = keras.layers.ActivityRegularization(l1=0.1)