API - How to have valid nullable fields in swagger ?

[fdescamps]

Hi,

Thanks for express-openapi. I really appreciate to use it :)
But I have a problem, I need to expose fields which the type strings that could be nullable.
This following code works when i run the server based on express-api :

responses: { 200: { schema: { title: 'MyObject', properties: { myfield: { type: ['string', 'null'],

But it's not valid against Swagger (editor.swagger.io) :(

Semantic error at definitions.MyObject.myfield "type" should be a string

Do you have a valid way to use nullable fields with express-openapi ?

Thanks by advance !

And Thanks for this top library.

Regards,

F.

[MugeSo]

At first, your question is not library matter but just OpenAPI (swagger) matter.
So I think you should ask it in other better place.

Answer is here:
OAI/OpenAPI-Specification#229

[jsdevel]

@fdescamps try using anyOf. Glad that you like the framework!

[fdescamps]

Hi,

Thanks for your answers.

I tried anyOf like that :

`
responses: {

200: {

  description: 'MySchema',

  schema: {

    title: 'Schema Example',

    properties: {

      myproperty: {

        example: 'myvalue',

        anyOf: [

          { type: 'string' },

          { type: 'null' },

        ],

      },

`

But when the nodejs is starting, an exception is thrown :

`express-openapi: Validating schema after populating paths

express-openapi: validation errors [
{

"property": "instance.paths./leads/{id}.get.responses[200]",

"message": "is not exactly one from <#/definitions/response>,<#/definitions/jsonReference>",

"schema": {

  "oneOf": [

    {

      "$ref": "#/definitions/response"

    },

    {

      "$ref": "#/definitions/jsonReference"

    }

  ]

},

[...]

"name": "oneOf",

"argument": [

  "<#/definitions/response>",

  "<#/definitions/jsonReference>"

],
"stack": "instance.paths./leads/{id}.get.responses[200] is not exactly one from <#/definitions/response>,<#/definitions/jsonReference>"

`

Do you know how to write a right anyOf ?

Thanks.

[fdescamps]

More Informations, oneOf is not valid, but allOf is valid

[jsdevel]

@fdescamps take a look at the openapi schema. It should have the answer you're looking for.

[jsdevel]

closing due to inactivity. let us know if you still have questions @fdescamps

[jsdevel]

@fdescamps I recently adding schema extension support. Should address this.

[lzear]

Is there a way to correctly validate requests/responses having nullable fields with OpenAPI v3?

The OAI specifies that nullable fields should use the keyword "nullable", which doesn't seem to be implemented in any JS library for validation.
There are several discussions related to this topic:
ajv-validator/ajv#486
OAI/OpenAPI-Specification#1389
OAI/OpenAPI-Specification#229

I started working on trying to convert OAI's syntax to JSON-schema's (see #127). Does it make sense to work in that direction?

[Frizzled]

The example in the test wouldn't pass validation until the quotes were removed from the $ref value:

$ref: #/definitions/schema

Error with quotes around #/definitions/schema is:

Error resolving $ref pointer "#/definitions/schema". 
Token "schema" does not exist.

[jsdevel]

@Frizzled which test are you referring to?