What should have been a fairly easy implementation turned into several frustrating hours. I was using the old Yelp API that is accessed simply by passing your yelp key in the url. But, I wanted to take advantage of some of the new functionality only available in their API version 2.0. Unfortunately Yelp API v2 requires an oAuth key/signature type access. Having already written similar code to access the Amazon web services with a signature I thought this would be a simple as reusing some existing code. Man was I wrong. Turns out a "correctly" implemented version of oAuth is much less tolerant than AWS is. Simple things, such as what characters in the URL must be encoded, invalidated the Yelp signature. After much searching and screwing around with various proposed implementations it became clear that the easiest and best implementation was to use the Java library provided by Yelp and simply access it from Coldfusion. To make this process easier I've consolidated th