Rspec: testing dalli cache (outside of rails)

Question

This might be outside the realm of what you should test, but how could one test a service method that uses caching (i.e. that it uses the cache):

def get_payment_methods(country_code, filter=[])
    key = "/countries/#{country_code.upcase}/payment_methods"
    payment_methods = CACHE.get(key)
    unless payment_methods
      payment_methods = My::Service.get_payment_methods_for_country(country_code.upcase).first
      CACHE.set(key, payment_methods)
    end
    # ...
end

score 1 · Accepted Answer · answered Dec 11 '13 at 01:13

You could create a CACHE double and verify the following for your method:

It calls the cache
It uses the cache value and doesn't get the payment method if the cached value is present
It gets the payment and saves the cache value if the cached value is not present

That's all pretty straightforward with RSpec

Rspec: testing dalli cache (outside of rails)

1 Answers1