30 Days Postman Developer: Day 18 The response body needs to be of type object, but we found an array instead

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24

@valensh1 I am also stucked with that error.

Schema is the same and I have copied the Response and saved it as the Example so everything matches. But somewhere still shows expected “object”… Hope someone helps us

25

I have the same issue. It looks like any change I do into the YAML Definition is not being saved and synced with the request validation. Even if I remove completly the YAML Definition, same error “The response body needs to be of type object, but we found an array instead” is being returned when sending the request and doing the validation.
Am I missing something in the Postman UI?

27

I have the same issue

28

hi!
I have the same issue.
here is my YAML
for schema ‘Cosmos’ i have type ‘array’ and items with apropriate type (‘object’) and properties etc.

openapi: "3.0.0"
info:
  version: 1.1.0
  title: Cosmos
  description: A sample API that retrieves constellations as an example to demonstrate features in the OpenAPI 3.0 specification
  license:
    name: MIT
servers:
  - url: https://{{server}}.mock.pstmn.io
paths:
  /cosmos:
    get:
      description: Returns all constellations in this sample dataset
      summary: List all cosmos
      operationId: listCosmos
      tags:
        - cosmos
      responses:
        "200":
          description: An array of constellations
          content:
            application/json:
              schema:
                $ref: "#/components/schemas/Cosmos"
        default:
          description: unexpected error
          content:
            application/json:
              schema:
                $ref: "#/components/schemas/Error"
  /cosmos/{cosmoId}:
    get:
      description: Returns a constellation based on a single ID
      summary: Info for a specific constellation
      operationId: showCosmoById
      tags:
        - cosmos
      parameters:
        - name: cosmoId
          in: path
          required: true
          description: The id of the constellation to retrieve
          schema:
            type: string
      responses:
        "200":
          description: Expected response to a valid request
          content:
            application/json:
              schema:
                $ref: "#/components/schemas/Cosmo"
        default:
          description: unexpected error
          content:
            application/json:
              schema:
                $ref: "#/components/schemas/Error"
components:
  schemas:
    Cosmos:
      type: array
      items:
        type: object
        required:
          - id
          - name
        properties:
          id:
            type: integer
            format: int64
          name:
            type: string
          tag:
            type: string
    Cosmo:
      type: object
      required:
        - code
        - message
      properties:
        id:
          type: integer
          format: int32
        name:
          type: string
        tag:
          type: string
        description:
          type: string
    Error:
      type: object
      required:
        - message
      properties:
        name:
          type: string
        message:
          type: string
        header:
          type: string

and there is still the same error: expect object but get array.
Why is object expected - this is what I do not quite understand.

29

Guys!
It seems to be a bug somewhere in POSTMAN app.
It looks like the changes made in index.yaml and saved do not affect actually the workflow in POSTMAN. (You can test it by yourselves by changing some schemas and sending requests).
Solution for me (except that I have corrected all the needed fields in index.yaml) was - to restart the POSTMAN app.