JSON data for rspec tests

In cases like this, I'll create fixture files for the JSON I want to import. Something like this can work:

json = JSON.parse(File.read("fixtures/valid_customer.json"))
customer = ImportsData.import(json)
customer.name.should eq(json["customer"]["name"])

I haven't seen something where you could use FactoryGirl to set attributes, then get it into JSON and import it. You'd likely need to create a mapper that will take your Customer object and render it in JSON, then import it.

Following Jesse's advice, in Rails 5 now you could use file_fixture (docs)

I just use a little helper for reading my json fixtures:

def json_data(filename:)
  file_content = file_fixture("#{filename}.json").read
  JSON.parse(file_content, symbolize_names: true)
end

Actually you can do the following with factorygirl.

factory :json_data, class: OpenStruct do 
   //fields
end

FactoryGirl.create(:json_data).marshal_dump.to_json

Here's something that works well for me. I want to create deeply nested structures without specifying individual factories for each nesting. My usecase is stubbing external apis with webmock. Fixtures don't cut it for me since I need to stub in a variety of different data.

Define the following base factory and support code:

FactoryBot.define do
  factory :json, class: Hash do
    # Don't try to persist the object
    skip_create
    # Grab only what is defined in the json block
    initialize_with { attributes[:json].to_json }
  end
end

I can then define the actual factory like this:

FactoryBot.define do
  factory :json_response, parent: :json do
    # You can define any attributes you want here
    # to use as parameters in the json block
    ids { [] }
    
    # The result of this block is what FactoryBot will return
    json do
      ids.map do |id|
        {
          score: 90,
          data: {
            id: id,
          },
        }
      end
    end
  end
end

Finally you can use it like this:

FactoryBot.build(:json_response, ids: [1,2])
=> "[{\"score\":90,\"data\":{\"id\":1}},{\"score\":90,\"data\":{\"id\":2}}]"

Sometime ago we implemented FactoryJSON gem that addresses this issue. It worked quite well for us so far. Readme file covers possible use cases.