Allow --extra_opset to accept a list of extra opsets. (#2136)

Signed-off-by: Jay Zhang <jiz@microsoft.com>

Author: fatcat-z

README.md

@@ -139,6 +139,7 @@ python -m tf2onnx.convert
     [--signature_def SIGNATURE_DEF]
     [--concrete_function CONCRETE_FUNCTION]
     [--target TARGET]
+    [--extra_opset list-of-extra-opset]
     [--custom-ops list-of-custom-ops]
     [--load_op_libraries tensorflow_library_path]
     [--large_model]
@@ -217,6 +218,11 @@ Only valid with parameter `--saved_model`. If a model contains a list of concret
 
 Some models require special handling to run on some runtimes. In particular, the model may use unsupported data types. Workarounds are activated with ```--target TARGET```. Currently supported values are listed on this [wiki](https://github.com/onnx/tensorflow-onnx/wiki/target). If your model will be run on Windows ML, you should specify the appropriate target value.
 
+#### --extra_opset
+
+If you want to convert a TF model using an existing custom op, this can specify the correspongding domain and version.
+The format is a comma-separated map of domain and version, for example: `ai.onnx.contrib:1`.
+
 #### --custom-ops
 
 If a model contains ops not recognized by onnx runtime, you can tag these ops with a custom op domain so that the

tf2onnx/convert.py

@@ -123,10 +123,14 @@ def get_args():
         if not args.tflite:
             parser.error("dequantize flag is currently only supported for tflite")
     if args.extra_opset:
-        tokens = args.extra_opset.split(':')
-        if len(tokens) != 2:
-            parser.error("invalid extra_opset argument")
-        args.extra_opset = [utils.make_opsetid(tokens[0], int(tokens[1]))]
+        all_extra_opsets = args.extra_opset.split(',')
+        extra_opset_list = []
+        for extra_opset in all_extra_opsets:
+            tokens = extra_opset.split(':')
+            if len(tokens) != 2:
+                parser.error("invalid extra_opset argument")
+            extra_opset_list.append(utils.make_opsetid(tokens[0], int(tokens[1])))
+        args.extra_opset = extra_opset_list
     if args.load_op_libraries:
         args.load_op_libraries = args.load_op_libraries.split(",")
     return args