This is an excellent post that explains a little bit behind the difficulty in testing external services https://robots.thoughtbot.com/how-to-stub-external-services-in-tests How to Stub External Services in Tests
One simple option is to use Webmock
Here is an example of using Webmock in a similar way to what VCR does - which is recording and reading from a file
stub_request(:any, "www.example.com").