JSON-Schema: Using relative URLs in $ref

Question

I'm having trouble using a parent schema that references a child schema via a relative URL.

Here's my parent schema:

{
  "$schema": "http://json-schema.org/draft-07/schema#",
  "description": "The parent schema.",
  "type": "object",
  "properties": {
    "parentProp1": { "type": "string"},
    "parentProp2": { "$ref": "child.json#"}
  }
}

Here's my child schema:

{
  "$schema": "http://json-schema.org/draft-07/schema#",
  "description": "The parent schema.",
  "type": "object",
  "properties": {
    "childProp1": { "type": "number" }
  }
}

Here's my data:

{
  "parentProp1": "one",
  "parentProp2": {
    "childProp1": 1
  }
}

Here's the error I get with ajv-cli :

$ ajv -s parent.json -d parent-test.json

schema parent.json is invalid

error: can't resolve reference child.json# from id #

I get a similar error (that child.json can't be resolved) with 3 other validators, which suggests my schema is incorrect.

What am I doing wrong?

Answer 1

Are you passing the child schema as a dependency? Most validators won't automatically load schemas and need to be told about each one explicitly. There is a way to do this with ajv-cli although the syntax it escapes me at the moment. Pretty sure if you get it to print the help for the command it will tell you, though.