Tavern error Structure of returned data was different than expected -

i have a test in tavern

test_name: Add products for tests

stages:
  - name: Add product one
    request:
      url: http://localhost:5566/product
      json:
        title: Product One
        description: Product One in our catalog
        picture: images/product.jpeg
        categories:
          - title: tshirt
          - title: casual
        price:
            currency: EUR
            units: 59
      method: POST
      headers:
        content-type: application/json
    response:
      status_code: 200
      headers:
        content-type: application/json
      save:
        json:
          product_id: uuid
    delay_after: 1

  - name: Get product one
    request:
      url: http://localhost:5566/product/{product_id}
      method: GET
      headers:
        content-type: application/json
    response:
      status_code: 200
      json:
        picture: images/product.jpeg
        title: Product One
      headers:
        content-type: application/json

the first stage is a POST that add the Product to the database the second stage is a GET with the uuid that is coming, as variable, from the first stage.

I want to check the response of the second stage and only two specific parameters. the picture and the title of the product

but i get the following error

ERROR    tavern.response.base:base.py:41 Structure of returned data was different than expected  - Extra keys in response: {'uuid', 'id', 'price_id', 'description'} (expected = '{'picture': 'images/product.jpeg', 'title': 'Product One'}' (type = <class 'dict'>), actual = '{'id': '1', 'uuid': '62c8c26d-c2c8-42a2-9111-2fd3186b08de', 'title': 'Product One', 'description': 'Product One in our catalog', 'picture': 'images/product.jpeg', 'price_id': '1'}' (type = <class 'dict'>))

is possible to define only a set of parameters or is mandatory to use the entire JSON structure?

thanks in advance

By default, headers are set to Strict: False, and JSON resp set to Strict: True.

They can be disabled globally, with a switch (--tavern-strict json:on headers:on), or in the test.yaml. Example.

---
test_name: Check github API

stages:
  - name: Make sure the JSON contains location

    request:
      url: https://api.github.com/users/6wl
      method: GET

    response:
      strict: False
      status_code: 200
      json:
        location: Manchester

Will only fail if location in the JSON resp does not equal Manchester.

https://buildmedia.readthedocs.org/media/pdf/tavern/stable/tavern.pdf

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