Error when there are array items with $ref in additionalProperties

[rovast]

error message

failed to resolve \"definitions\" in fragment in URI: \"#/definitions/BaseDictResp\": struct field \"definitions\" not found

Preliminary Analysis

kin-openapi/openapi2conv/openapi2_conv.go

Line 550 in cea0a13

func toV3AdditionalProperties(from openapi3.AdditionalProperties) openapi3.AdditionalProperties {

fails to handle additionalProperties.items, which results in item.$refs not being properly converted by toV3Ref. As a consequence, the following remains unchanged:

"items": {
  "$ref": "#/definitions/BaseDictResp"
}

This leads to the inability to find #/definitions/BaseDictResp.

test openapi2 json

{
  "swagger": "2.0",
  "info": {
    "description": "Test for additionalProperties",
    "version": "v1",
    "title": "API Test"
  },
  "host": "Test",
  "paths": {
    "/map": {
      "post": {
        "summary": "api test summary",
        "description": "api test description",
        "operationId": "apiTestUsingPOST",
        "consumes": ["application/json"],
        "produces": ["*/*"],
        "responses": {
          "200": {
            "description": "OK",
            "schema": {
              "$ref": "#/definitions/ResponseOfMap"
            }
          }
        }
      }
    }
  },
  "definitions": {
    "BaseDictResp": {
      "type": "object",
      "properties": {
        "key": {
          "type": "string",
          "description": "key of map"
        },
        "value": {
          "type": "string",
          "description": "value of map"
        }
      },
      "title": "BaseDictResp",
      "description": "BaseDictResp description"
    },

    "ResponseOfMap": {
      "type": "object",
      "properties": {
        "data": {
          "type": "object",
          "description": "response data",
          "additionalProperties": {
            "type": "array",
            "items": {
              "$ref": "#/definitions/BaseDictResp"
            }
          }
        }
      },
      "title": "ResponseOfMap"
    }
  }
}

[roberth1988]

I got the same issue ... so digged deeper... effectively:

kin-openapi/openapi2conv/openapi2_conv.go

Line 557 in cea0a13

func convertRefsInV3SchemaRef(from *openapi3.SchemaRef) *openapi3.SchemaRef {

needs to be changed to

func convertRefsInV3SchemaRef(from *openapi3.SchemaRef) *openapi3.SchemaRef {
	if from == nil {
		return nil
	}
	to := *from

	to.Ref = ToV3Ref(to.Ref)
	if to.Value != nil {
		v := *from.Value
		to.Value = &v
		if to.Value.Items != nil {
			to.Value.Items.Ref = ToV3Ref(to.Value.Items.Ref)
		}
		to.Value.AdditionalProperties = toV3AdditionalProperties(to.Value.AdditionalProperties)
	}

	return &to
}

[kovacsbela]

@fenollp would you cut a release with this please? I am at v0.127.0 because of this can't go to v0.131.0, but then that has a CVE.

[fenollp]

Done https://github.com/getkin/kin-openapi/releases/tag/v0.132.0 :)