JSON schema validation Draft 7 two type of data for one field - python-3.x

Question

I need help creating a JSON schema for a value that could be an object, or an array of objects.
lib: jsonschema==3.2.0
py: 3.8
I have 2 responses from the server:
first:
{
"result": [
{
"brand": "Test"
}
]}
second:
{
"result":
{
"brand": "Test"
}
}
As you can see the difference between both in the first case its an array of obj the second just object.
my schema:
{
"$schema": "http://json-schema.org/draft-07/schema",
"$id": "http://example.com/example.json",
"type": "object",
"required": [
"result"
],
"properties": {
"result": {
"$id": "#/properties/result",
"type": ["array", "object"],
"additionalItems": true,
"items": {
"$id": "#/properties/result/items",
"anyOf": [
{
"$id": "#/properties/result/items/anyOf/0",
"type": "object",
"required": [
"brand"
],
"properties": {
"brand": {
"$id": "#/properties/result/items/anyOf/0/properties/brand",
"type": "string"
}
},
"additionalProperties": true
}
]
}
}
},
"additionalProperties": true}
In the first case when return array, it checks the "brand" type on the second when return object, no.
How I can set up 2 types for one field "result" that it could check the brand type?

Answer 1

Your schema can be fixed as follows:
{
"$schema": "http://json-schema.org/draft-07/schema",
"$id": "http://example.com/example.json",
"type": "object",
"required": [
"result"
],
"properties": {
"result": {
"$id": "#/properties/result",
"anyOf": [
{
"$id": "#/properties/result/items/brand",
"type": "object",
"properties": {
"brand": {
"$id": "#/properties/result/items/anyOf/0/properties/brand",
"type": "string"
}
},
"required": [
"brand"
],
"additionalProperties": true
},
{
"$id": "#/properties/result/items/array",
"type": "array",
"items": {
"$ref": "#/properties/result/items/brand"
}
}
]
}
},
"additionalProperties": true
}
Demos here, here and here.
However, it is customary to extract reusable portions of a schema into a separate "definitions" section, like so:
{
"$schema": "http://json-schema.org/draft-07/schema",
"$id": "http://example.com/example.json",
"definitions": {
"brand": {
"type": "object",
"properties": {
"brand": {
"$id": "#/properties/result/items/anyOf/0/properties/brand",
"type": "string"
}
},
"required": [
"brand"
],
"additionalProperties": true
}
},
"type": "object",
"required": [
"result"
],
"properties": {
"result": {
"$id": "#/properties/result",
"anyOf": [
{
"$ref": "#/definitions/brand"
},
{
"$id": "#/properties/result/items/array",
"type": "array",
"items": {
"$ref": "#/definitions/brand"
}
}
]
}
},
"additionalProperties": true
}
Demos here, here and here.
Notes:
To express that the property "result" may be of two different types, use the "anyof" keyword for the property's schema. The value of the "anyOf" should be an array with the schemas for each possible type (here the "brand" object or an array of "brand" objects) as the array items.
See: Multiple Types.
To avoid duplicating the definitions for the "brand" object, you can use the "$ref" when defining a schema for the array's items to refer back to the previously given schema for "brand". As noted above it s customary to place reused subschemas into a "definitions" section, but it is not necessary, "$ref" can refer to any schema item via the JSON Pointer syntax.
See: Reuse.
When the items of a list have a single schema, "additionalItems" should not be used.
See: List validation.