In a quick post to her blog today, Lorna Mitchell talks about an issue with pecl_outh tat came up during her development of a new API. A strange fatal error message was breaking her connection.

I'd gone through all the handshaking steps, got the acces token and was ready to start talking to the service itself. However when I tried to call OAuth::fetch, I got an error message: Fatal error: Uncaught exception 'OAuthException' with message 'Invalid protected resource url, unable to generate signature base string'

As it turns out, the issue was obscure - the address she was connecting to was missing a training slash (http://api.localhost versus http://api.localhost/) and it was causing the OAuth fetch to fail (apparently undocumented). If you're interested in some of the other things that have come up in her work with OAuth on the project, see here.