OasValidation Policy: Having a problem with oneOf inside an allOf inside an oneOf

[mctocci]

Greetings team!

I have an OpenAPI spec with a POST operation that can contain one of three models in the request:  Thing1, Thing2, Thing3.

The Thing models “inherit” from ThingBase, which contains a property common to all Things, which all use allOff to include this “base” class.

Thing3 differs from Things1 & 2 in that one of its properties is a object that is a oneOf.

Here is the spec:

openapi: 3.0.0
info:
  version: '1.0'
  title: Apigee OasValidation POC
servers:
  - url: 'http://localhost:3000'
paths:
  /things:
    post:
      summary: Your POST endpoint
      operationId: post-things
      requestBody:
        content:
          application/json:
            schema:
              oneOf:
                - $ref: '#/components/schemas/Thing1'
                - $ref: '#/components/schemas/Thing2'
                - $ref: '#/components/schemas/Thing3'
            examples:
              Example 1:
                value:
                  ThingId: 0
                  Thing1Property: string
      responses:
        '201':
          description: Created
          content:
            application/json:
              schema: {}
      servers:
        - url: 'http://localhost:3000'
components:
  schemas:
    Thing1:
      title: Thing1
      allOf:
        - $ref: '#/components/schemas/ThingBase'
        - type: object
          additionalProperties: false
          properties:
            Thing1Property:
              type: string
    ThingBase:
      type: object
      title: ThingBase
      additionalProperties: false
      properties:
        ThingId:
          type: number
    Thing2:
      title: Thing2
      allOf:
        - $ref: '#/components/schemas/ThingBase'
        - type: object
          additionalProperties: false
          properties:
            Thing2Property:
              type: string
    Thing3:
      title: Thing3
      allOf:
        - $ref: '#/components/schemas/ThingBase'
        - $ref: '#/components/schemas/Context'
    Context:
      type: object
      title: Context
      oneOf:
        - type: object
          additionalProperties: false
          properties:
            Property1:
              type: string
        - type: object
          additionalProperties: false
          properties:
            Property2:
              type: string

I've configured an OasValidation policy in my proxy to validate incoming requests against this spec.

Things1 and 2 validate correctly when POSTed in a request, but Thing3 fails when sending this body:

{
  "ThingId": 0,
  "Property1": "string"
}

The error message:

 "OASValidation OAS-Validation with resource \"oas://Apigee-OasValidation-oneOf-POC (2).yaml\": failed with reason: \"[ERROR - Instance failed to match exactly one schema (matched 0 out of 3): [/oneOf/0: Object instance has properties which are not allowed by the schema: [\"Property1\"], /oneOf/1: Object instance has properties which are not allowed by the schema: [\"Property1\"], /oneOf/2: Object instance has properties which are not allowed by the schema: [\"Property1\"]]\n\tERROR - Object instance has properties which are not allowed by the schema: [\"Property1\"]: []\n\tERROR - Object instance has properties which are not allowed by the schema: [\"Property1\"]: []\n\tERROR - Object instance has properties which are not allowed by the schema: [\"Property1\"]: []]\"",

I would expect /oneOf/2 would be a match for the request body.

It seems that request should be valid.

Is this a bug, or am I doing something wrong?

If I alter Context to not use a oneOf, validation succeeds, but I really need a oneOf. 😉

Thanks!