schema references require a wrapping object

When using referencing schemas to define the request or response body, express-openapi-validator seems to require a wrapping object in order to pass request and response validation.

Given the following spec:

openapi: 3.0.2
servers:
  - url: http://localhost:9000/
info:
  description: Campaign API
  version: 0.0.1
  title: Campaign API
paths:
  /campaign:
    post:
      summary: Create campaign
      requestBody:
        required: true
        content:
          application/json:
            schema:
              $ref: '#/components/schemas/CreateCampaign'
      responses:
        '201':
          description: Campaign successfully created
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/CampaignResponse'
components:
  schemas:
    CampaignResponse:
      type: object
      required:
        - id
        - name
        - description
        - startDate
        - createdAt
        - updatedAt
      properties:
        id:
          type: integer
        name:
          type: string
        description:
          type: string
        startDate:
          type: string
          format: date-time
        endDate:
          type: string
          format: date-time
        createdAt:
          type: string
          format: date-time
        updateAt:
          type: string
          format: date-time
    CreateCampaign:
      type: object
      required:
        - name
        - description
        - startDate
      properties:
        name:
          type: string
        description:
          type: string
        startDate:
          type: string
          format: date-time
        endDate:
          type: string
          format: date-time

Expected Behavior

I should be able to send a POST with body

{
    "name": "test",
    "description": "description",
    "startDate": "2020-08-25T20:37:33.117Z",
    "endDate": "2020-08-25T20:37:33.117Z"
}

Actual behavior

The spec has a valid schema and does not error out when it is installed. In addition, my swagger docs also believe this to be perfectly valid:

However, sending the request results in the following error:

Bad Request: request should have required property 'body'
    at Object.POST-/campaign-application/json (.../node_modules/express-openapi-validator/dist/middlewares/openapi.request.validator.js:95:31)
    at RequestValidator.validate (.../node_modules/express-openapi-validator/dist/middlewares/openapi.request.validator.js:52:41)
    at requestValidationHandler (.../node_modules/express-openapi-validator/dist/index.js:162:79)
    at newFn (.../node_modules/express-async-errors/index.js:16:20)
    at Layer.handle [as handle_request] (.../node_modules/express/lib/router/layer.js:95:5)
    at trim_prefix (.../node_modules/express/lib/router/index.js:317:13)
    at .../node_modules/express/lib/router/index.js:284:7
    at Function.process_params (.../node_modules/express/lib/router/index.js:335:12)
    at next (.../node_modules/express/lib/router/index.js:275:10)
    at .../node_modules/express-openapi-validator/dist/middlewares/openapi.multipart.js:56:13

Workaround

After playing around, I was able to get satisfy the validator by changing up the spec like so:

schema:
  properties:
    campaign:
      $ref: '#/components/schemas/CreateCampaign'

But then my swagger docs believe that I need to wrap all the data like so:

And based off of my reading from openapi docs, I believe the first example should be valid.

[rogerzxu]

@cdimascio Thanks for your help!

The bodyParser middleware was indeed the issue. In my case, I had it included in my original code, but had neglected to include it in the sample project. The reason it wasn’t working in my original code was because I had it registered after the openapi spec was installed, but before the route definitions. The code here states:

// 2. Set up body parsers for the request body types you expect
//    Must be specified prior to endpoints in 5.

which I think is inaccurate? I found that the validation wouldn’t work correctly unless the bodyParser is registered before the openapi installation.

I also updated my repo with the fix as well as some misc cleanup changes, please feel free to reference it.

[cdimascio]

On another note, many other have also decided to use 'swagger-ui-express' alongside express-openapi-validator

Would you mind fixing up your repo and perhaps renaming to something like openapi-swagger-ui-example? If you decide to do so. Also, use either the async/await based install or the v4.0.0-alpha.1 install which uses standard connect middleware.

This repo you created provides a a nice simple, example, of how to use express-openapi-validator with swagger-express-ui. Once cleaned up, I may consider referencing it from the swagger-ui FAQ question in the README.