Fix import error with latest version of onnx, closes #907

Author: davidmezzetti

.github/workflows/build.yml

@@ -49,7 +49,7 @@ jobs:
       - name: Build
         run: |
           pip install -U wheel
-          pip install .[all,dev] onnx==1.17.0 skl2onnx==1.18.0
+          pip install .[all,dev]
           pip cache purge
           python -c "import nltk; nltk.download(['punkt', 'punkt_tab', 'averaged_perceptron_tagger_eng'])"
           python --version

src/python/txtai/pipeline/train/mlonnx.py

@@ -5,9 +5,14 @@
 from ..base import Pipeline
 
 try:
+    # Workaround for issue with onnx 1.18 and onnxmltools 1.13
+    import onnx
+
+    onnx.helper.split_complex_to_pairs = None
+
     from onnxmltools import convert_sklearn
-    from onnxmltools.convert.common.data_types import StringTensorType
 
+    from skl2onnx.common.data_types import StringTensorType
     from skl2onnx.helpers.onnx_helper import save_onnx_model, select_model_inputs_outputs
 
     ONNX_MLTOOLS = True