Bug: OpenAPI plugin function name parsing results in invalid kernel function name

[TaoChenOSU]

Describe the bug
The fallback mechanism in handling an OpenAPI operation that doesn't have an operation ID may result in invalid kernel function name: https://github.com/microsoft/semantic-kernel/blob/main/python/semantic_kernel/connectors/openapi_plugin/openapi_parser.py#L239

Traceback (most recent call last):
  File "C:\Users\taochen\Project\semantic-kernel\python\semantic_kernel\functions\kernel_function_from_method.py", line 69, in __init__
    metadata = KernelFunctionMetadata(
               ^^^^^^^^^^^^^^^^^^^^^^^
  File "C:\Users\taochen\Project\semantic-kernel\python\.venv\Lib\site-packages\pydantic\main.py", line 253, in __init__
    validated_self = self.__pydantic_validator__.validate_python(data, self_instance=self)
                     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
pydantic_core._pydantic_core.ValidationError: 1 validation error for KernelFunctionMetadata
name
  String should match pattern '^[0-9A-Za-z_-]+$' [type=string_pattern_mismatch, input_value='/anything_patch', input_type=str]
    For further information visit https://errors.pydantic.dev/2.11/v/string_pattern_mismatch

To Reproduce
Steps to reproduce the behavior:

1. Go to sample: https://github.com/microsoft/semantic-kernel/tree/main/python/samples/concepts/plugins/openapi
2. Open openapi.yaml
3. Comment out line 11
4. Run openapi_client.py

Expected behavior
The plugin is successfully added to the kernel.

Platform

• Language: Python

Additional context
We should either require the operationId attribute or perform some more meaningful parsing and a more targeted error message.

[sshandilya1991]

hey @TaoChenOSU / @moonbox3
I surmise this is due to this

I can raise a fix for this - but here is a question:

• do we want to fail/raise if operationId is not present ? If yes, then is it the right place to fail or we should fail a little before in parsing logic.
• if we don't want to raise/throw (assuming operationId is not obtained from details object) - the variable operationId would be something like /users_get which is going to fail the regex validation. So, question is to either to make the regex validation flexible or making sure operationId in details exists or maybe something else that I may be missing.

thoughts?

Edit:
I see that anyway we are directly using operation.id in further functions assuming it's there anyway - so, IMO, we should simply have a validation for it & raise if it's not there or probably create one if not there in openapispec(wild thought) ?

[moonbox3]

Hi, @sshandilya1991, yes, we should have validation for it early on and raise if operationId isn't present.