Fix index_table_from_file to allow vocabulary_file be a Tensor

PiperOrigin-RevId: 157740677

2 files changed, 23 insertions, 4 deletions

diff --git a/tensorflow/contrib/lookup/lookup_ops.py b/tensorflow/contrib/lookup/lookup_ops.py
index 65474f03fa..e49b62afa2 100644
--- a/tensorflow/contrib/lookup/lookup_ops.py
+++ b/tensorflow/contrib/lookup/lookup_ops.py
@@ -871,7 +871,7 @@ def index_table_from_file(vocabulary_file=None,
   ```
 
   Args:
-    vocabulary_file: The vocabulary filename.
+    vocabulary_file: The vocabulary filename, may be a constant scalar `Tensor`.
     num_oov_buckets: The number of out-of-vocabulary buckets.
     vocab_size: Number of the elements in the vocabulary, if known.
     default_value: The value to use for out-of-vocabulary feature values.
@@ -889,8 +889,9 @@ def index_table_from_file(vocabulary_file=None,
     ValueError: If `num_oov_buckets` is negative or `vocab_size` is not greater
       than zero.
   """
-  if not vocabulary_file:
-    raise ValueError("vocabulary_file must be specified.")
+  if vocabulary_file is None or (
+      isinstance(vocabulary_file, str) and not vocabulary_file):
+    raise ValueError("vocabulary_file must be specified and must not be empty.")
   if num_oov_buckets < 0:
     raise ValueError("num_oov_buckets must be greater or equal than 0, got %d."
                      % num_oov_buckets)
diff --git a/tensorflow/contrib/lookup/lookup_ops_test.py b/tensorflow/contrib/lookup/lookup_ops_test.py
index 5ec169b6db..180dfefe29 100644
--- a/tensorflow/contrib/lookup/lookup_ops_test.py
+++ b/tensorflow/contrib/lookup/lookup_ops_test.py
@@ -1187,6 +1187,18 @@ class IndexTableFromFile(test.TestCase):
       lookup_ops.tables_initializer().run()
       self.assertAllEqual((1, 2, 3), ids.eval())
 
+  def test_string_index_table_from_file_tensor_filename(self):
+    vocabulary_file = self._createVocabFile("f2i_vocab1.txt")
+    with self.test_session():
+      vocabulary_file = constant_op.constant(vocabulary_file)
+      table = lookup.index_table_from_file(
+          vocabulary_file=vocabulary_file, num_oov_buckets=1)
+      ids = table.lookup(constant_op.constant(["salad", "surgery", "tarkus"]))
+
+      self.assertRaises(errors_impl.OpError, ids.eval)
+      lookup_ops.tables_initializer().run()
+      self.assertAllEqual((1, 2, 3), ids.eval())
+
   def test_int32_index_table_from_file(self):
     vocabulary_file = self._createVocabFile(
         "f2i_vocab2.txt", values=("42", "1", "-1000"))
@@ -1245,7 +1257,13 @@ class IndexTableFromFile(test.TestCase):
               860),  # 3 + fingerprint("toccata") mod 300.
           ids.eval())
 
-  def test_index_table_from_file_with_only_oov_buckets(self):
+  def test_index_table_from_file_fails_with_empty_vocabulary_file_name(self):
+    self.assertRaises(
+        ValueError,
+        lookup.index_table_from_file,
+        vocabulary_file="")
+
+  def test_index_table_from_file_fails_with_empty_vocabulary(self):
     self.assertRaises(
         ValueError,
         lookup.index_table_from_file,