How do I inherit from schemas that are in the same file? - json

Question

Given the following schema fragment
{
"$schema": "http://json-schema.org/schema#",
"definitions": {
"uuid": {
"title": "uuid",
"description": "UUID ( http://regex101.com/r/eJ7gN2 )",
"type": "string",
"minLength": 36,
"maxLength": 36,
"pattern": "^[0-9a-fA-F]{8}-[0-9a-fA-F]{4}-[0-9a-fA-F]{4}-[0-9a-fA-F]{4}-[0-9a-fA-F]{12}$"
},
"reference": {
"title": "reference",
"description": "A reference to an object by UUID",
"type": "object",
"properties" : {
"id": {
"$ref": "#/definitions/uuid"
}
},
"required": [ "id" ]
},
"imageref": {
"title": "imageref",
"description": "Reference to an image using an internal UUID",
"type": "object",
"properties": {
"size": {
"description": "Largest side of the image, depends on aspect ratio",
"type": "integer",
"minimum": 0,
"maximum": 1600
},
"crop": {
"description": "Flag to tell the system to crop the image or not",
"type": "boolean",
"default": false
}
}
}
}
}
How do I specify that imageref should inherit from reference, so that imageref has the id property that is in reference?
I have lots of other things that will be reference types and I am trying to eliminate duplicating that definition over and over again.

Answer 1

To inherit from another schema, you use allOf combined with $ref:
{
"title": "Extension schema",
"allOf": [{"$ref": "/path/to/base/schema"}]
}
Inheriting from another schema within the same file is just the same - you reference it using fragments, just like you have elsewhere:
{
"title": "Extension schema",
"allOf": [{"$ref": "#/definitions/reference"}]
}