How to ask for a specific format in Rspec request?

Question

The get_children method of my Playgrounds controller renders a specific javascript template, or json formated data:

# GET children from playground
def get_children
  @business_areas = @playground.business_areas.visible.order(:sort_code)

  respond_to do |format|
    format.json { render json: @business_areas }
    format.js # uses specific template to handle js
  end
end

When requesting this method with Rspec tests, I get the following error message: ActionController::UnknownFormat. For the test, the playground and one child business area have been created in advance:

  describe "get_children - GET /playgrounds/:id/get_children" do
    it "renders a successful response" do
      get get_children_playground_url(playground)
      expect(response).to be_successful
    end

    it "renders the expected object" do
      get get_children_playground_url(playground)
      parsed_body = JSON.parse(response.body)
      expect(parsed_body[:name][:en]).to eq('Test Business Area')
    end
  end

Reading around, I found some references about request.accept = "application/json" but I didn't manage to have it working.

How and where shall I set the expected output format for the method call?

Thanks for yout help!

PS: RSpec version is 3.12

Answer 1

describe "GET /playgrounds/:id/get_children" do
  it "renders an html response" do
    get get_children_playground_url(playground)
    expect(response.content_type).to eq "text/html; charset=utf-8"
  end

  it "renders a json response" do
    # NOTE: using Accept header
    # get get_children_playground_url(playground), headers: {Accept: "application/json"}
    # NOTE: using .json url extension
    get get_children_playground_url(playground, format: :json)
    expect(response.content_type).to eq "application/json; charset=utf-8"
  end

  it "renders a js response" do
    # get get_children_playground_url(playground), headers: {Accept: "text/javascript", HTTP_X_REQUESTED_WITH: "XMLHttpRequest"}
    # NOTE:         there is an option for all that ^                                    ^ this one is to avoid cross origin error
    get get_children_playground_url(playground), xhr: true
    expect(response.content_type).to eq "text/javascript; charset=utf-8"
  end 
end

...
    renders an html response
    renders a json response
    renders a js response

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3 examples, 0 failures

https://api.rubyonrails.org/classes/ActionDispatch/Integration/Session.html#method-i-process