allOf-test.json

{
    "swagger": "2.0",
    "info": {
        "version": "1.0.0",
        "title": "API",
        "description": "API"
    },
    "schemes": [
        "http"
    ],
    "paths": {
        "/test1": {
            "get": {
                "description": "Test1",
                "produces": [
                    "application/json"
                ],
                "responses": {
                    "200": {
                        "$ref": "#/responses/default"
                    }
                }
            }
        },
        "/test2": {
            "get": {
                "description": "Test2",
                "produces": [
                    "application/json"
                ],
                "responses": {
                    "200": {
                        "description": "response",
                        "schema": {
                            "allOf": [
                                {
                                    "$ref": "#/definitions/response"
                                },
                                {
                                    "type": "object",
                                    "properties": {
                                        "token": {
                                            "type": "string"
                                        }
                                    }
                                }
                            ]
                        }
                    }
                }
            }
        }
    },
    "definitions": {
        "response": {
            "properties": {
                "errorCode": {
                    "default": 0,
                    "type": "integer",
                    "enum": [
                        0,
                        1,
                        2,
                        3,
                        4,
                        5,
                        6,
                        7,
                        8,
                        9,
                        10,
                        11,
                        12
                    ],
                    "description": "Status code"
                },
                "success": {
                    "default": true,
                    "type": "boolean",
                    "description": "Success flag"
                }
            }
        }
    },
    "responses": {
        "default": {
            "description": "response",
            "schema": {
                "$ref": "#/definitions/response"
            }
        }
    }
}

allOf-test.yaml

swagger: '2.0'

info:
  version: "1.0.0"
  title: API
  description: API

schemes:
  - http
  
paths:
  /test1:
    get:
      description: Test1
      produces:
        - application/json
      responses:
        '200':
            $ref: '#/responses/default'
  /test2:
    get:
      description: Test2
      produces:
        - application/json
      responses:
        '200':
          description: response
          schema:
            allOf:
            - $ref: '#/definitions/response'
            - type: object
              properties:
                token:
                  type: string

definitions:
  response:
    properties:
      errorCode:
        default: 0
        type: integer
        enum: [0,1,2,3,4,5,6,7,8,9,10,11,12]
        description:  Status code
      success:
        default: true
        type: boolean
        description: Success flag
        
responses:
  default: 
    description: response
    schema:
      $ref: '#/definitions/response'