Parameter example is undefined for $ref schema parameters

[homemdasneves]

If a spec has a reference schema parameter with an example like sortDirection here:

"/api/v1/application/Area/list": {
      "post": {
        "tags": [
          "Area"
        ],
        "summary": "Retrieve a list of records of entity type",
        "operationId": "Area_GetMany",
        "parameters": [
          {
            "name": "sortDirection",
            "in": "query",
            "description": "Direction to sort by",
            "schema": {
              "$ref": "#/components/schemas/SortDirection"
            },
            "example": "asc"
          },
...

we won't get "asc" in the value, we'll get <string> instead:

{
    "id": "c9dbad06-eeb4-4771-8d8e-5b471483b9e5",
    "name": "Retrieve a list of records of entity type",
    "request": {
        "name": "Retrieve a list of records of entity type",
        "description": {},
        "url": {
            "path": [
                "api",
                "v1",
                "application",
                "Area",
                "list"
            ],
            "host": [
                "{{baseUrl}}"
            ],
            "query": [
                {
                    "disabled": false,
                    "key": "sortDirection",
                    "value": "<string>",
                    "description": "Direction to sort by"
                },
...

But, if the schema is inline, like below:

"/api/v1/application/UnitType/list": {
      "post": {
        "tags": [
          "UnitType"
        ],
        "summary": "Retrieve a list of records of entity type",
        "operationId": "UnitType_GetMany",
        "parameters": [
          {
            "name": "sortDirection",
            "in": "query",
            "description": "Direction to sort by",
            "schema": {
              "enum": [
                "asc",
                "desc"
              ],
              "type": "string"
            },
            "example": "asc"
          },

the value is correctly filled as asc in the generated postman collection:

{
    "id": "b4a0b4df-ed78-4245-ac62-17dc4f5c2775",
    "name": "Retrieve a list of records of entity type",
    "request": {
        "name": "Retrieve a list of records of entity type",
        "description": {},
        "url": {
            "path": [
                "api",
                "v1",
                "application",
                "UnitType",
                "list"
            ],
            "host": [
                "{{baseUrl}}"
            ],
            "query": [
                {
                    "disabled": false,
                    "key": "sortDirection",
                    "value": "asc",
                    "description": "Direction to sort by"
                },
...

As a workaround, in order to have a valid value upon generation, we can set a default value in the $ref schema parameter.

This could be related with #401 and #559

[VShingala]

@homemdasneves Could you also add the schema for SortDirection component? We validate the value defined against the corresponding schema and if example is not valid according to schema then depending upon option we use random value or <string> as a placeholder.

[VShingala]

Issue is reproducible with following schema.

openapi: '3.0.0'
info:
  version: '1.0.0'
  title: 'Sample API'
  description: Buy or rent spacecrafts

paths:
  /spacecrafts/{spacecraftId}:
    parameters:
      - $ref: '#/components/parameters/args.userId'
    get:
      summary: Read a spacecraft
      parameters:
        - name: hello
          in: query
          description: Direction to sort by 1
          schema:
            type: string
          example: asc
        - name: world
          in: query
          description: Direction to sort by 2
          schema:
            $ref: '#/components/schemas/SpacecraftId'
          example: asc
      responses:
        '200':
          description: The spacecraft corresponding to the provided `spacecraftId`
          content:
            application/x-www-form-urlencoded:
              schema:
                $ref: '#/components/schemas/Spacecraft'
            application/json:
              schema:
                $ref: '#/components/schemas/Space
components:
  parameters:
    args.userId:
      name: spacecraftId
      description: The unique identifier of the spacecraft
      in: path
      required: true
      schema:
        $ref: '#/components/schemas/SpacecraftId'
  schemas:
    SpacecraftId:
      description: The unique identifier of a spacecraft
      type: string
    Spacecraft:
      type: object
      required:
        - id
        - name
        - type
      properties:
        id:
          $ref: '#/components/schemas/SpacecraftId'
        name:
          type: string
        type:
          type: string
          enum:
            - capsule
            - probe
            - satellite
            - spaceplane
            - station
        description:
          type: string
    Error:
      type: object
      required:
        - message
      properties:
        message:
          description: A human readable error message
          type: string
  securitySchemes:
    bearer:
      type: http
      scheme: bearer
security:
  - bearer: []