Add string strip text operator (#460)

* add string strip text operator

---------

Co-authored-by: Wenbing Li <10278425+wenbingl@users.noreply.github.com>

operators/text/string_strip.cc

@@ -0,0 +1,54 @@
+// Copyright (c) Microsoft Corporation. All rights reserved.
+// Licensed under the MIT License.
+
+#include "string_strip.hpp"
+#include "string_tensor.h"
+#include <vector>
+#include <cmath>
+#include <algorithm>
+
+const char* WHITE_SPACE_CHARS = " \t\n\r\f\v";
+
+KernelStringStrip::KernelStringStrip(const OrtApi& api, const OrtKernelInfo& info) : BaseKernel(api, info) {
+}
+
+void KernelStringStrip::Compute(OrtKernelContext* context) {
+  // Setup inputs
+  const OrtValue* input_X = ort_.KernelContext_GetInput(context, 0);
+  std::vector<std::string> X;
+  GetTensorMutableDataString(api_, ort_, context, input_X, X);
+
+  // For each string in input, replace with whitespace-trimmed version.
+  for (size_t i = 0; i < X.size(); ++i) {
+    size_t nonWhitespaceBegin = X[i].find_first_not_of(WHITE_SPACE_CHARS);
+    if (nonWhitespaceBegin != std::string::npos) {
+      size_t nonWhitespaceEnd = X[i].find_last_not_of(WHITE_SPACE_CHARS);
+      size_t nonWhitespaceRange = nonWhitespaceEnd - nonWhitespaceBegin + 1;
+
+      X[i] = X[i].substr(nonWhitespaceBegin, nonWhitespaceRange);
+    }
+  }
+
+  // Fills the output
+  OrtTensorDimensions dimensions(ort_, input_X);
+  OrtValue* output = ort_.KernelContext_GetOutput(context, 0, dimensions.data(), dimensions.size());
+  FillTensorDataString(api_, ort_, context, X, output);
+}
+
+const char* CustomOpStringStrip::GetName() const { return "StringStrip"; };
+
+size_t CustomOpStringStrip::GetInputTypeCount() const {
+  return 1;
+};
+
+ONNXTensorElementDataType CustomOpStringStrip::GetInputType(size_t /*index*/) const {
+  return ONNX_TENSOR_ELEMENT_DATA_TYPE_STRING;
+};
+
+size_t CustomOpStringStrip::GetOutputTypeCount() const {
+  return 1;
+};
+
+ONNXTensorElementDataType CustomOpStringStrip::GetOutputType(size_t /*index*/) const {
+  return ONNX_TENSOR_ELEMENT_DATA_TYPE_STRING;
+};

operators/text/string_strip.hpp

@@ -0,0 +1,20 @@
+// Copyright (c) Microsoft Corporation. All rights reserved.
+// Licensed under the MIT License.
+
+#pragma once
+
+#include "ocos.h"
+#include "string_utils.h"
+
+struct KernelStringStrip : BaseKernel {
+  KernelStringStrip(const OrtApi& api, const OrtKernelInfo& info);
+  void Compute(OrtKernelContext* context);
+};
+
+struct CustomOpStringStrip : OrtW::CustomOpBase<CustomOpStringStrip, KernelStringStrip> {
+  const char* GetName() const;
+  size_t GetInputTypeCount() const;
+  ONNXTensorElementDataType GetInputType(size_t index) const;
+  size_t GetOutputTypeCount() const;
+  ONNXTensorElementDataType GetOutputType(size_t index) const;
+};

operators/text/text.cc

@@ -4,6 +4,7 @@
 #include "text/string_join.hpp"
 #include "text/string_lower.hpp"
 #include "text/string_split.hpp"
+#include "text/string_strip.hpp"
 #include "text/string_to_vector.hpp"
 #include "text/string_upper.hpp"
 #include "text/vector_to_string.hpp"
@@ -17,15 +18,14 @@
 #if defined(ENABLE_RE2_REGEX)
 #include "text/re2_strings/string_regex_replace.hpp"
 #include "text/re2_strings/string_regex_split.hpp"
-#endif // ENABLE_RE2_REGEX
+#endif  // ENABLE_RE2_REGEX
 
-
-FxLoadCustomOpFactory LoadCustomOpClasses_Text = 
-    LoadCustomOpClasses<CustomOpClassBegin, 
+FxLoadCustomOpFactory LoadCustomOpClasses_Text =
+    LoadCustomOpClasses<CustomOpClassBegin,
 #if defined(ENABLE_RE2_REGEX)
                         CustomOpStringRegexReplace,
                         CustomOpStringRegexSplitWithOffsets,
-#endif // ENABLE_RE2_REGEX
+#endif  // ENABLE_RE2_REGEX
                         CustomOpRaggedTensorToDense,
                         CustomOpRaggedTensorToSparse,
                         CustomOpStringRaggedTensorToDense,
@@ -38,10 +38,10 @@ FxLoadCustomOpFactory LoadCustomOpClasses_Text =
                         CustomOpStringMapping,
                         CustomOpMaskedFill,
                         CustomOpStringSplit,
+                        CustomOpStringStrip,
                         CustomOpStringToVector,
                         CustomOpVectorToString,
                         CustomOpStringLength,
                         CustomOpStringConcat,
                         CustomOpStringECMARegexReplace,
-                        CustomOpStringECMARegexSplitWithOffsets
-                        >;
+                        CustomOpStringECMARegexSplitWithOffsets>;

test/test_string_ops.py

@@ -173,6 +173,22 @@ def _create_test_model_string_equal(prefix, domain='ai.onnx.contrib'):
     return model
 
 
+def _create_test_model_string_strip(prefix, domain='ai.onnx.contrib'):
+    nodes = []
+    nodes[0:] = [helper.make_node('Identity', ['input_1'], ['identity1'])]
+    nodes[1:] = [helper.make_node('%sStringStrip' % prefix,
+                                  ['identity1'], ['customout'],
+                                  domain=domain)]
+
+    input0 = helper.make_tensor_value_info(
+        'input_1', onnx_proto.TensorProto.STRING, [None, None])
+    output0 = helper.make_tensor_value_info(
+        'customout', onnx_proto.TensorProto.STRING, [None, None])
+
+    graph = helper.make_graph(nodes, 'test0', [input0], [output0])
+    model = make_onnx_model(graph)
+    return model
+
 def _create_test_model_string_split(prefix, domain='ai.onnx.contrib'):
     nodes = []
     nodes.append(helper.make_node('Identity', ['input'], ['id1']))
@@ -436,6 +452,26 @@ class TestPythonOpString(unittest.TestCase):
         for t in type_list:
             self.assertIn(t, def_list)
 
+    def test_string_strip_cc(self):
+        so = _ort.SessionOptions()
+        so.register_custom_ops_library(_get_library_path())
+        onnx_model = _create_test_model_string_strip('')
+        self.assertIn('op_type: "StringStrip"', str(onnx_model))
+        sess = _ort.InferenceSession(onnx_model.SerializeToString(), so)
+        input_1 = np.array([["  a b c  "]])
+        txout = sess.run(None, {'input_1': input_1})
+        self.assertEqual(txout[0].tolist(), np.array([["a b c"]]).tolist())
+
+    def test_string_strip_cc_empty(self):
+        so = _ort.SessionOptions()
+        so.register_custom_ops_library(_get_library_path())
+        onnx_model = _create_test_model_string_strip('')
+        self.assertIn('op_type: "StringStrip"', str(onnx_model))
+        sess = _ort.InferenceSession(onnx_model.SerializeToString(), so)
+        input_1 = np.array([[""]])
+        txout = sess.run(None, {'input_1': input_1})
+        self.assertEqual(txout[0].tolist(), np.array([[""]]).tolist())
+
     def test_string_upper_cc(self):
         so = _ort.SessionOptions()
         so.register_custom_ops_library(_get_library_path())
@@ -1151,7 +1187,6 @@ class TestPythonOpString(unittest.TestCase):
                 res.__len__ = lambda self: len(vocab)
 
             vocab_table = _CreateTable(["want", "##want", "##ed", "wa", "un", "runn", "##ing"])
-
             text = tf.convert_to_tensor(["unwanted running", "unwantedX running"], dtype=tf.string)
             try:
                 tf_tokens, tf_rows, tf_begins, tf_ends = (