how to use nullable attribute in examples?

[sybrands-place]

How can I get a null example value for a type string? (while using OpenAPI 3.0.3)

"errorDescription" : {
   "title" : "The errorDescription schema",
   "type" : "string",
   "nullable": true
}

When I use the example above, I get "errorDescription": "string", as a result

When I add "default": null there's a [FATAL] Error while mocking schema ...

(maybe updating ajv is a solution? https://ajv.js.org/v6-to-v8-migration.html)

[jormaechea]

Hi @sybrands-place, can you provide a minimal OpenAPI schema to reproduce the issue? This way I can find a solution faster.

[sybrands-place]

Sure, here's an example:

  "openapi": "3.0.1",
  "info": {
    "title": "Dummy OpenAPI Mock server with nullable String",
    "version": "1.0.0"
  },
  "servers": [
    {
      "url": "http://localhost:8080",
      "description": "Swagger Mock Server URL"
    }
  ],
  "paths": {
    "/dummy": {
      "get": {
        "summary": "Get dummy information",
        "operationId": "getDummyInformation",
        "responses": {
          "200": {
          "description": "OK",
          "content": {
              "application/json": {
                "schema": {
                  "type": "object",
                  "required": [ 
                    "contactpersonResponse",
                    "additionalProperties"
                  ],
                  "properties": {
                    "dummyDescription": {
                      "title": "The dummyDescription schema",
                      "type": "string",
                      "nullable": true
                    },
                    "extraDescription": {
                      "title": "The extraDescription schema",
                      "type": "object",
                      "default": {}
                    }
                  },
                  "example": {
                    "dummyDescription": null,
                    "extraDescription": {}
                  }
                }
              }
            }
          }
        }
      }
    }
  }
}

In this case with an example it works (i.e. dummyDescription becomes null), but if you remove the example the value for dummyDescription becomes "string". Perhaps this is how it should work, that it only works if you provide an example? I tried setting the default value to null, but as mentioned before then there's an error message.

EDIT: my original post might be misleading together with this message. Then it didn't work even with an example, but it was because the example was for a child element and not the complete element. So I guess that's clear to me now. I only need the verification that default doesn't work with a nullable String. Thanks for suggesting to make a simpler example, that helped! ;)

[jormaechea]

@sybrands-place sorry for the delay, I've been really busy. I'm now working on allowing null examples and default values, it should be ready soon.

[jormaechea]

Feature released in v1.10.0