jsonschema Required properties inoperative with $ref - json

Question

I am going to write json schema to verify tree data.
Schema consisting of top root and block below.
There may be another block below the block.
Schema for validation.
schema = {
"$schema": "http://json-schema.org/draft-04/schema",
"$ref": "#/definitions/root",
"definitions":{
"root": {
"properties": {
"name": {
"type": "string"
},
"children": {
"type": "array",
"items": [
{"$ref":"#/definitions/block"}
]
}
},
"required": ["name", "children"]
},
"block": {
"properties": {
"name": {
"type": "string"
},
"children": {
"type": "array",
"items": [
{"$ref":"#/definitions/block"}
]
}
},
"required": ["name"]
}
}
}
Below is incorrect data for testing. The last name properties do not exist.
{
"name": "group8",
"children": [
{
"name": "group7",
"children": [
{
"name": "group6",
"children": [
{
"name": "group5",
"children": [
{ ###### wrong
"children": []
}
]
}
]
}
]
}
]
}
This data validates well, but it doesn't work on a slightly complex tree.
# Error: ValidationError: file /home/gulliver/.local/lib/python2.7/site-packages/jsonschema/validators.py line 934: 'name' is a required property #
{
"name": "group8",
"children": [
{
"name": "group7",
"children": [
{
"name": "group6",
"children": [
{
"name": "group12",
"children": [
{
"name": "group11",
"children": [
{
"name": "group10",
"children": []
}
]
}
]
},
{
"name": "group9",
"children": [
{
"name": "group5",
"children": [
{ ####### wrong
"children": []
}
]
}
]
}
]
}
]
},
{
"name": "group13",
"children": [
{
"name": "null1",
"children": []
}
]
}
]
}
It does not work when the data at the bottom of the tree is invalid.
My guess is that the branch splits and this happens, does anyone know why or how to fix it?
I tested using python and jsonschema.

Answer 1

When items is an array, it applies the subschema values to the same index location in the array in the instance.
For example, where you define...
"items": [
{"$ref":"#/definitions/block"}
]
only the first item in the array will be tested. It has nothing to do with deep nesting. For example, the follwing data is valid according to your schema...
{
"name": "group8",
"children": [
{
"name": "group7"
},
{
"something": "else",
"Not": "name"
}
]
}
(Live demo: https://jsonschema.dev/s/etFGE)
If you modify your use of items, then it will work like you expect:
"items": {"$ref":"#/definitions/block"}
(do this for both uses)
Live demo: https://jsonschema.dev/s/rk1OD