It seems Amazon FPS is broken for me. The generated integration link is blank and the test breaks:
./manage.py test billing.AmazonFPSTestCase
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Traceback (most recent call last):
File "/Users/hakan/Sites/merchant_test/example/billing/tests/amazon_fps_tests.py", line 24, in testLinkGen
self.assertEquals(pregen_link, link.strip())
AssertionError: '<a href="https://authorize.payments-sandbox.amazon.com/cobranded-ui/actions/start?callerKey=AKIAJ2AXTZNZRXZTJWDA&callerReference=100&paymentReason=Digital%20Download&pipelineName=SingleUse&returnURL=http%3A%2F%2Flocalhost%2Ffps%2Ffps-return-url%2F&signature=oSnkew7oCBPVk0IVZAjO87Ogsp4EO7jRlELaFwtqWzY%3D&signatureMethod=HmacSHA256&signatureVersion=2&transactionAmount=30"><img src="http://g-ecx.images-amazon.com/images/G/01/cba/b/p3.gif" alt="Amazon Payments" /></a>' != u'<a href=""><img src="http://g-ecx.images-amazon.com/images/G/01/cba/b/p3.gif" alt="Amazon Payments" /></a>
Further research shows that the issue is in the link_url method of AmazonFPSIntegration here: https://github.com/agiliq/merchant/blob/master/billing/integrations/amazon_fps_integration.py#L58
A call is being make to the make_url method of boto.fps.connection.FPSConnection, which has been renamed to cbui_url in the latest version of boto (2.5.2) (see here: https://github.com/boto/boto/blob/develop/boto/fps/connection.py#L198 and here: https://github.com/boto/boto/commit/d4e1d221f142b79a529130888c588f6e83c58bf3#L2L174)
What version of boto should we be using to use django-merchant? It would be helpful to include version information alongside the requirements in the documentation.