Building an OpenAPI response, including oneOf, and maybe allOf - swagger-ui

Question

I am trying to build up a response from a variety of schema components using OpenAPI 3. There are basically three parts to the response:
A shared component that other endpoints use (i.e. success/failure flags). - #/components/schemas/core_response_schema inside allOf.
Properties that all responses on this endpoint use (i.e., user_id) - the properties component of the below.
One of several schemas that will vary depending on the type of user. - the oneOf component.
I've determined that I have to use allOf to be able to mix properties (item 2) and the core response (item 1), though this feels wrong as there's only one item. I tried a $ref, but it didn't work.
The below successfully passes three different OpenAPI linting tools, but in the example it builds, Swagger UI does not show the item 2 things (properties), and does show all of the item 3 things (should be oneOf).
"responses": {
"200": {
"description": "Operation successfully executed.",
"content": {
"application/json": {
"schema": {
"properties": {
"user_id": {
"$ref": "#/components/schemas/user_id"
},
"results": {
"type": "array",
"items": {
"$ref": "#/components/schemas/result_user_by_id"
}
}
},
"type": "object",
"allOf": [
{
"$ref": "#/components/schemas/core_response_schema"
}
],
"oneOf": [
{
"$ref": "#/components/schemas/user_type_a"
},
{
"$ref": "#/components/schemas/user_type_b"
},
{
"$ref": "#/components/schemas/user_type_c"
}
]
}
}
}
}
},
"components": {
"schemas": {
"core_response_schema": {
"properties": {
"success": {
"description": "A flag indicating whether the request was successfully completed or not.",
"type": "boolean"
},
"num_results": {
"description": "The number of results for this request",
"type": "integer"
}
},
"type": "object"
},
"user_id": {
"description": "Unique 10 character `user_id`.",
"type": "string",
"maxLength": 10,
"minLength": 10,
"example": "a1b2c3d4e5"
},
}
}
And example payloads for two users. Type A and B (it's a contrived example).
User Type A:
{
"success": true,
"num_results": 1,
"user_id": "c1b00cb714",
"results": [{
"user_type": "a",
"group_id": "e7a99e3769",
"name": null,
"title": null,
... (and so on until we get to the stuff that's unique to this type of user) ...
"favourite_artworks": [
"sunflowers",
"landscapes"
],
"artwork_urls": [
"http://sunflowers.example"
]
}
]
}
User Type B:
{
"success": true,
"num_results": 1,
"user_id": "c1b00cb715",
"results": [{
"user_type": "B",
"group_id": "e7a99e3769",
"name": null,
"title": null,
... (and so on until we get to the stuff that's unique to this type of user) ...
"supported_charities": [
"UN Foundations"
],
"charity_urls": [
"http://www.un.int"
],
}
]
}
What's the correct way to merge together different schemas and properties in OpenAPI? Is this right and Swagger UI just can't handle it?
And how do you mix a schema with properties without having to use allOf?
This suggests it's possible: Swagger Schema: oneOf, anyOf, allOf valid at the same time?

Answer 1

After further investigation, I've determined this is a bug in swagger-ui - https://github.com/swagger-api/swagger-ui/issues/3803 - they simply don't support oneOf (or anyOf) currently.
As far as at least three different linting tools are concerned, a mixture of anyOf, oneOf, and allOf can be used together in the same schema.
Redoc appears to have similar problems - https://github.com/Rebilly/ReDoc/issues/641