Can't resolve reference from id

[grosswilerp]

Since Apikana now creates schema draft7 it replaces the id with $id and now the validation fails when using references inside definitions that use $id. However, the JSON schema itself is actually valid, but it seems that ajv is not able to compile it properly.

Here is an example schema:

{
  type: "object",
  $id: "test",
  properties: {
    foo: {type: "integer"},
    bar: {type: "string"},
    "spec": {
        "$ref": "#/definitions/TopicSpecDescriptor",
        "description": "Topic specification."
    }
  },
  definitions: {
    "TopicSpecDescriptor": {
        "type": "object",
        "properties": {
            "partitions": {
              "$ref": "#/definitions/Int",
              "description": "Number of partitions.\nNormally 10.\nSee <a href=\"https://kafka.apache.org/documentation/#intro_concepts_and_terms\" target=”_blank”>Kafka concepts and terms</a>"
            }
        },
        "$id": "TopicSpecDescriptor"
    },
    "Int": {
        "type": "integer"
    }
  },
  required: ["foo"],
  additionalProperties: false
}

It validates without any error on JSON Schema Validator but when using ajv, it fails with this error:

  missingRef: 'TopicSpecDescriptor#/definitions/Int',
  missingSchema: 'TopicSpecDescriptor' 

If I remove the $id from the schema, it works as usual. But I don't think that's a good approach, especially since Apikana creates the JSON schema using $id now.