Returns a Association object from storage that matches the server_url. Returns nil if no such association is found or if the one matching association is expired. (Is allowed to GC expired associations when found.)

If there is a matching association, remove it from the store and return true, otherwise return false.

Put a Association object into storage. When implementing a store, don‘t assume that there are any limitations on the character set of the server_url. In particular, expect to see unescaped non-url-safe characters in the server_url field.

Return true if the nonce has not been used before, and store it for a while to make sure someone doesn‘t try to use the same value again. Return false if the nonce has already been used or if the timestamp is not current. You can use OpenID::Store::Nonce::SKEW for your timestamp window. server_url: URL of the server from which the nonce originated timestamp: time the nonce was created in seconds since unix epoch salt: A random string that makes two nonces issued by a server in

      the same second unique

Convert a lifetime in seconds into a memcache expiry value