Issue with JSON.net anyOf schema validation - json

Question

I'm using the JSON.Net schema validation package and I've come across a very strange issue. I have tracked down the issue to a use of anyOf in the anyObject definition below:
{
"$schema": "http://json-schema.org/draft-07/schema#",
"$id": "http://example.com/schemas/example/1.0/schema.json",
"anyOf": [
{
"$ref": "#/definitions/anyObject"
}
],
"definitions": {
"anyObject": {
"type": "object",
"properties": {
"type": {
"type": "string"
}
},
"required": [
"type"
],
"anyOf": [
{
"if": {
"properties": {
"type": {
"const": "typeA"
}
}
},
"then": {
"$ref": "#/definitions/typeA"
},
"else": false
},
{
"if": {
"properties": {
"type": {
"const": "typeB"
}
}
},
"then": {
"$ref": "#/definitions/typeB"
},
"else": false
}
]
},
"bodyDefinition": {
"oneOf": [
{
"if": {
"properties": {
"$computed": {
"type": "string"
}
},
"required": [
"$computed"
]
},
"then": {
"$ref": "#/definitions/computedBody"
},
"else": {
"$ref": "#/definitions/wildcardBody"
}
},
{
"type": "string"
}
]
},
"wildcardBody": {
"type": "object",
"additionalProperties": {
"$ref": "#/definitions/bodyDefinition"
}
},
"firstComputedValue": {
"type": "object",
"additionalProperties": false,
"properties": {
"$computed": {
"const": "first"
},
"values": {
"type": "array",
"minItems": 1,
"items": {
"$ref": "#/definitions/bodyDefinition"
}
}
},
"required": [
"$computed",
"values"
]
},
"computedBody": {
"oneOf": [
{
"if": {
"properties": {
"$computed": {
"const": "first"
}
}
},
"then": {
"$ref": "#/definitions/firstComputedValue"
},
"else": false
}
]
},
"typeA": {
"type": "object",
"additionalProperties": false,
"properties": {
"type": {
"type": "string",
"const": "typeA"
},
"body": {
"$ref": "#/definitions/bodyDefinition"
}
},
"required": [
"type"
]
},
"typeB": {
"type": "object",
"additionalProperties": false,
"properties": {
"type": {
"type": "string",
"const": "typeB"
},
"body": {
"$ref": "#/definitions/bodyDefinition"
}
},
"required": [
"type"
]
}
}
}
When I test this json:
{
"type": "typeB",
"body":{
"$computed":"first",
"values":[]
}
}
It should be marked as invalid, because values is required to have at least one value. However it is valid. The below JSON should be considered valid, and the above schema does assert that correctly:
{
"type": "typeB",
"body":{
"$computed":"first",
"values":["foo"]
}
}
If I remove typeA from the anyObject definition, then the validation is performed correctly. Below is the schema that validates correctly:
{
"$schema": "http://json-schema.org/draft-07/schema#",
"$id": "http://example.com/schemas/example/1.0/schema.json",
"anyOf": [
{
"$ref": "#/definitions/anyObject"
}
],
"definitions": {
"anyObject": {
"type": "object",
"properties": {
"type": {
"type": "string"
}
},
"required": [
"type"
],
"anyOf": [
{
"if": {
"properties": {
"type": {
"const": "typeB"
}
}
},
"then": {
"$ref": "#/definitions/typeB"
},
"else": false
}
]
},
"bodyDefinition": {
"oneOf": [
{
"if": {
"properties": {
"$computed": {
"type": "string"
}
},
"required": [
"$computed"
]
},
"then": {
"$ref": "#/definitions/computedBody"
},
"else": {
"$ref": "#/definitions/wildcardBody"
}
},
{
"type": "string"
}
]
},
"wildcardBody": {
"type": "object",
"additionalProperties": {
"$ref": "#/definitions/bodyDefinition"
}
},
"firstComputedValue": {
"type": "object",
"additionalProperties": false,
"properties": {
"$computed": {
"const": "first"
},
"values": {
"type": "array",
"minItems": 1,
"items": {
"$ref": "#/definitions/bodyDefinition"
}
}
},
"required": [
"$computed",
"values"
]
},
"computedBody": {
"oneOf": [
{
"if": {
"properties": {
"$computed": {
"const": "first"
}
}
},
"then": {
"$ref": "#/definitions/firstComputedValue"
},
"else": false
}
]
},
"typeA": {
"type": "object",
"additionalProperties": false,
"properties": {
"type": {
"type": "string",
"const": "typeA"
},
"body": {
"$ref": "#/definitions/bodyDefinition"
}
},
"required": [
"type"
]
},
"typeB": {
"type": "object",
"additionalProperties": false,
"properties": {
"type": {
"type": "string",
"const": "typeB"
},
"body": {
"$ref": "#/definitions/bodyDefinition"
}
},
"required": [
"type"
]
}
}
}
Can anyone see if there is an issue with this definition, or is this an issue with the JSON.Net schema package?
This testing was done against the online version of the schema validator at https://www.jsonschemavalidator.net/

Answer 1

I think this is a bug. I'll speak to the library author about it!
To debug, I followed the validation process through the schema, setting $ref or then or else to false... when I reached computedBody, I changed it to the following...
"computedBody": {
"if": {
"properties": {
"$computed": {
"const": "first"
}
}
},
"then": false,
"else": false
}
Validation still comes back positive, which shouldn't be possible. I proved it reaches computedBody by setting that subschema to false and seeing validation come back negative.
(the oneOf wrapping the subschema of computedBody isn't needed. if is valid at the schema level just fine).