tf.TensorSpec == InputDesc

tensorpack/graph_builder/model_desc.py

@@ -7,10 +7,15 @@ import tensorflow as tf
 
 from ..models.regularize import regularize_cost_from_collection
 from ..tfutils.tower import get_current_tower_context
+from ..tfutils.common import get_tf_version_tuple
 from ..utils import logger
 from ..utils.argtools import memoized_method
 from ..utils.develop import log_deprecated
 
+if get_tf_version_tuple() >= (1, 7):
+    from tensorflow.python.framework.tensor_spec import TensorSpec
+
+
 __all__ = ['InputDesc', 'ModelDesc', 'ModelDescBase']
 
 
@@ -71,7 +76,7 @@ class InputDesc(
         self._cached_placeholder[graph] = placeholder
 
     @staticmethod
-    def from_placeholder(placeholder):
+    def _from_placeholder(placeholder):
         name = placeholder.op.name
         if name.endswith('_1') or name.endswith('_2'):
             logger.error("Creating InputDesc from a placeholder named {}.".format(name))
@@ -83,6 +88,11 @@ class InputDesc(
         ret._register_cached_placeholder(placeholder)
         return ret
 
+    @staticmethod
+    def _from_tensor_spec(spec):
+        assert spec.name is not None, "TensorSpec should have a name!"
+        return InputDesc(spec.dtype, tuple(spec.shape.as_list()), spec.name)
+
 
 class ModelDescBase(object):
     """
@@ -106,9 +116,14 @@ class ModelDescBase(object):
         except NotImplementedError:
             with tf.Graph().as_default() as G:   # create these placeholder in a temporary graph
                 inputs = self.inputs()
+                if isinstance(inputs[0], tf.Tensor):
                     for p in inputs:
                         assert p.graph == G, "Placeholders returned by inputs() should be created inside inputs()!"
-                return [InputDesc.from_placeholder(p) for p in inputs]
+                    return [InputDesc._from_placeholder(p) for p in inputs]
+                else:
+                    for p in inputs:
+                        assert isinstance(p, TensorSpec), type(p)
+                    return [InputDesc._from_tensor_spec(p) for p in inputs]
 
     @property
     def input_names(self):
@@ -123,16 +138,17 @@ class ModelDescBase(object):
 
     def inputs(self):
         """
-        __Create__ and returns a list of placeholders.
+        Returns a list of :class:`tf.TensorSpec` or placeholders.
         A subclass is expected to implement this method.
 
-        The placeholders __have to__ be created inside this method.
-        Don't return placeholders created in other methods.
+        If returning placeholders,
+        the placeholders __have to__ be created inside this method.
+        Don't return placeholders created in other places.
 
         Also, you should never call this method by yourself.
 
         Returns:
-            a list of `tf.placeholder`, to be converted to :class:`InputDesc`.
+            list[tf.placeholder] or list[tf.TensorSpec], to be converted to :class:`InputDesc`.
         """
         raise NotImplementedError()