GSoC 2011 Integration with External APIs: OAuth Roundtrip - Week 3

I've been developing generic methods to handle OAuth. When developing software it's important to create meaningful abstractions so a method can refer to these abstractions without need to understand low-level details what they do. For the OAuth part of my project a helper module handles this low-level details and caller that refers to these abstractions is an access_checker. It asks following questions:

• Get access token for user.
• Create a service for user.
• Generate a OAuth authorization URL.
• Process URL for OAuth verifications.

Low-level helper module does following operations for questions above:

Get access token for user:

• Generate a unique key consists of user's key and current host (different consumer key,secret so different services and access tokens are used for each hosts). 
• Ask memcache or a storage mechanism to fetch token corresponding to that key.
• Return token.
• If there isn't a token return None.

Create a service for user:

Service is a GDocsService object that is used to make API calls.

• Create a service for the current host. 
• Set service's input parematers to host's consumer_key and consumer_secret. 
• Set encryption method to sha or rsa.
• Return service.

Generate a OAuth authorization URL:

• Fetch a request token. 
• Save request token's secret to memcache for later use (when validating token).
• Generate a authorization URL from request token.
• Return URL.

Process URL for OAuth verifications:

• If request URL contains a verification key as GET parameter, parse it.
• Verify previously stored access token with parsed verification key.
• Store verified access token to memcache or datastore.