[BUG][aspnetcore] Use enum in query string throws 400

[yilinjuang]

Bug Report Checklist

• Have you provided a full/minimal spec to reproduce the issue?
• Have you validated the input using an OpenAPI validator (example)?
• What's the version of OpenAPI Generator used?
• Have you search for related issues/PRs?
• What's the actual output vs expected output?
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Description

Use enum in query string throws 400. EnumMember attribute is not considered by validation.

openapi-generator version

4.1.0

OpenAPI declaration file content or url

openapi: 3.0.2
info:
  title: Test
  version: 0.1.0
servers:
  - url: http://localhost
paths:
  /:
    get:
      operationId: test
      parameters:
        - name: param
          in: query
          required: true
          schema:
            $ref: '#/components/schemas/EnumParam'
      responses:
        200:
          description: test
components:
  schemas:
    EnumParam:
      type: string
      enum:
        - apple
        - orange

Command line used for generation

openapi-generator generate -g aspnetcore -o test -i openapi.yaml

Steps to reproduce

Call endpoint with query string ?param=apple throws validation error 400.

Related issues/PRs

Suggest a fix

According to link

The reason you are getting that error is Json.NET isn't the library converting the enum so the EnumMember attributes are not being used. You can get around this by writing a TypeConverter and applying it to your enum:

Maybe add a TypeConverter or just name the enum members without Enum suffix?

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[yilinjuang]

Fixed by #3557