How can I test the amazon api?

Question

I have the following code.

How can I test the function create_items_by_parent_asin?

def get_amazon():
    return AmazonAPI(settings.AMAZON_ACCESS_KEY, settings.AMAZON_SECRET_KEY, settings.AMAZON_ASSOC_TAG)

def get_item_by_asin(asin: str, response_group='Large'):
    amazon = get_amazon()
    product = amazon.lookup(ItemId=asin, ResponseGroup=response_group)
    return product

def create_items_by_parent_asin(self, asin: str):
    amazon_item = get_item_by_asin(asin, response_group='Large')
    ....

Answer 1

You don't test the API, you mock the interactions with amazon away with a different implementation of AmazonAPI.

In python this can be done using unittest.mock: https://docs.python.org/3/library/unittest.mock.html

It's been a long time since I've done this in python, but iirc you can just do something like this in your testclasses (untested, I adapted the example from the docs):

testproduct = ... # static product you will use in your tests
with patch('AmazonAPI') as mock:
    instance = mock.return_value
    instance.lookup.return_value = testproduct
    product = x.create_items_by_parent_asin("...") # this should now be your testproduct

If product is a non-trivial thing to create an instance of you can also mock this away by doing:

testproduct = Mock()
testproduct.<method you want to mock>.return_value = ...