I understand the basic concept of oAuth, but I don't understand how to implement it, from a line-by-line standpoint. I'm looking for a basic walkthrough of how to leverage oAuth to authenticate a PHP-powered application to access a user's data. I'd highly prefer the walk-through not explain how to use oAuth to work with any particular service (e.g., Twitter, Facebook, FitBit), but rather that it keep the walkthrough pretty vanilla. I would classify myself as being an intermediate PHP developer. Does such a walkthrough exist?
When using the Tumblr API, how exactly do I get the 'access_token' and 'access_secret' keys I need to post through my account via a script. [more inside]
How do you securely store OAuth credentials as a provider? (1.0a, 2-legged) [more inside]
When implementing OAuth2, is it possible to pass authorization to a second client, similar to proxy authentication in CAS? [more inside]
I'm working on a Twitter client that I intend to eventually post to Projects, but I've hit a stumbling block with OAuth authentication. [more inside]