redoc-cli - discriminators handled neither correctly nor consistently

[onavratil-monetplus]

Consider the following specs

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'

All of the prop1, prop2 should be the same (only difference is that $ref is expanded in prop1) and also prop2 and request schema of /another-path should be the same (same $ref target). All of them should have select box on testType property.

However, we can see the output here.

I'm using redoc-cli via npm in the latest version

$ redoc-cli --version
0.13.20

[onavratil-monetplus]

Supplementary info:
using same OAS, with

$ redoc-cli --version
0.9.1

yields the expected result

So this must have been introduced somewhere along the way.

[onavratil-monetplus]

Eventually - I am able to produce the expected result even with 0.13.20, however, I need to drop openapi version to

openapi: 3.0.3

This may be a workaround for this MWE, however, i cannot force-downgrade my OAS version, so I leave the bug open.

[AlexVarchuk]

Sorry but we already do not support redoc-cli. Please use @redocly/cli instead. If something is wrong in Redoc please reopen the issue.

PS: you can use build-docs command. Documentation is here

[RomanHotsiy]

Looks like the issue is not with redoc-cli only, I can reproduce it with Redoc lib.

Reopening.

Looks like happening when two properties of the same object have discriminator.

[onavratil-monetplus]

Thanks for swift reply, I don't think its caused by two properties, since this reproduces the issue

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:
                prop2:
                  $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'

[RomanHotsiy]

You're right 👍
Thanks.

[RomanHotsiy]

There is a workaround, add discriminator property to the schema and it will be working in both cases.

UPD: mistake

[RomanHotsiy]

@onavratil-monetplus changing oneOf to anyOf resolves the issue. Hopefully you can use this workaround for now.

[onavratil-monetplus]

The anyOf workaround seems to work, although it makes the interface a little less "tight".

Just to clarify the goal. I am aiming for a following structure, which tends to re-appear quite often in my APIs:

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: |
        I want to be able to use:
        * A polymorph reference to the parent, which means - it may be either child 1 or child 2 (some endpoints can accept/return any of these two)
        * A specific reference to Child 1 and/or Child 2 (some endpoints accept/return only one instance type)
      requestBody:
        content:
          application/json:
            schema:
              title: Test
              type: object
              properties:
                propPolymorph:
                  $ref: '#/components/schemas/parent'
                propChild1:
                  $ref: '#/components/schemas/child1'
                propChild2:
                  $ref: '#/components/schemas/child2'
      tags:
        - sample tag
components:
  schemas:
    parent:
      title: Polymorph Parent
      type: object
      oneOf:
        - $ref: '#/components/schemas/child1'
        - $ref: '#/components/schemas/child2'
      discriminator:
        propertyName: childType
        mapping:
          CHILD_1: '#/components/schemas/child1'
          CHILD_2: '#/components/schemas/child2'
      required:
        - childType
    child1:
      title: Specific Child 1
      type: object
      properties:
        childType:
          const: CHILD_1
        child1Property:
          type: integer
          description: Property for child 1
        child1OtherProperty:
          type: integer
          description: Other property for child 1
      required:
        - child1Property
    child2:
      title: Specific Child 2
      type: object
      properties:
        childType:
          const: CHILD_2
        child2Property:
          type: boolean
          description: Property for child 2
      required:
        - child2Property

I will need to run more tests with codegen anyways.