Redoc-cli discriminator

Question

I have redoc-cli installed via npm

$ redoc-cli --version
0.13.20

Now I use it to build docs with the following

openapi: 3.1.0
info:
  title: Sample API
  version: '1.0'
  contact:
    email: some@email.com
  description: Api description.
tags:
  - name: sample tag
    description: tag description
servers:
  - url: http://localhost:3000
paths:
  /int/methods/list:
    post:
      summary: Sample op
      operationId: sample-op
      description: Op description.
      requestBody:
        content:
          application/json:
            schema:
              type: object
              properties:
                test:
                  $ref: '#/components/schemas/test'
      tags:
        - sample tag
components:
  schemas:
    test1:
      title: Test
      type: object
      properties:
        testType:
          type: string
        testOne:
          type: string
    test2:
      title: Test 2
      type: object
      properties:
        testType:
          type: string
        testTwo:
          type: number
    test:
      title: Test Polymorph
      oneOf:
        - $ref: '#/components/schemas/test1'
        - $ref: '#/components/schemas/test2'
      discriminator:
        propertyName: testType
        mapping:
          ONE: '#/components/schemas/test1'
          TWO: '#/components/schemas/test2'

Still attempting to

$ redoc-cli build 04_interface/test.yaml
Prerendering docs

🎉 bundled successfully in: redoc-static.html (1061 KiB) [⏱ 0.179s]

Gives me a result as-if the whole discriminator was missing, ie

...instaed of the expected select box, as documented in redocly

I know redocly and redoc-cli are not the same, but redoc-cli used to support discriminators in the past, just at some point it seems to me that it stopped working - or there is some syntax niche I am missing.

Answer 1

So i found what the turning point is. Look at this example.

openapi: 3.1.0
info:
  title: Sample API
  version: '1.0'
  contact:
    email: some@email.com
  description: Api description.
tags:
  - name: sample tag
    description: tag description
servers:
  - url: http://localhost:3000
paths:
  /sample-path:
    post:
      summary: Sample op
      operationId: sample-op
      description: Op description.
      requestBody:
        content:
          application/json:
            schema:
              title: Test
              type: object
              properties:
                prop1:
                  title: Test Polymorph
                  oneOf:
                    - $ref: '#/components/schemas/test1'
                    - $ref: '#/components/schemas/test2'
                  discriminator:
                    propertyName: testType
                    mapping:
                      ONE: '#/components/schemas/test1'
                      TWO: '#/components/schemas/test2'
                prop2:
                  $ref: '#/components/schemas/testPolymorph'
      tags:
        - sample tag
  /another-path:
    post:
      summary: Another op
      operationId: another-op
      description: Another op description.
      requestBody:
        content:
          application/json:
            schema:
              $ref: '#/components/schemas/testPolymorph'
      tags:
        - sample tag
components:
  schemas:
    test1:
      title: Test - Variant 1
      type: object
      properties:
        testType:
          type: string
        testOne:
          type: string
    test2:
      title: Test Variant 2
      type: object
      properties:
        testType:
          type: string
        testTwo:
          type: number
    testPolymorph:
      title: Test Polymorph
      discriminator:
        propertyName: testType
        mapping:
          ONE: '#/components/schemas/test1'
          TWO: '#/components/schemas/test2'
      oneOf:
        - $ref: '#/components/schemas/test1'
        - $ref: '#/components/schemas/test2'

This specs yields the following visualization

It seems the discriminator doesnt work for $refs, only if the $ref is on the top schema level.

I started an issue here https://github.com/Redocly/redoc/issues/2252