Different anonymous users cannot vote separately

Problem/Motivation

I am working on a site using the Voting API module and the Like & Dislike module. I would like to allow anonymous users to vote.

This module saves a vote_source (by default the IP address) for each vote, so this should be possible. The problem is that when a module (here Like & Dislike) asks how many times the current user has voted by calling VoteStorage::getUserVotes() the vote_source is ignored. If the current user is anonymous, and a different anonymous user has voted, it looks as though the currrent user has already voted.

Proposed resolution

Add an optional parameter to VoteStorage::getUserVotes() specifying the vote source. If the parameter is omitted, and the user is anonymous, then use the default callback for the vote type.

Whenever the user is anonymous, count only votes for the matching vote_source, whether passed in or from the default.

Make corresponding changes to the VoteStorage::deleteUserVotes() method.

Remaining tasks

• Write a patch.
• Review the patch.
• Update the documentation.

User interface changes

None.

API changes

This changes the public API of the VoteStorage class. It adds an optional parameter to the getUserVotes() and deleteUserVotes() methods, and it changes the behavior of these method when the user is anonymous (whether or not the optional parameter is supplied). IMHO, the change in behavior is a bug fix.

Modules that use the Voting API and manage the vote source themselves (using Vote::setSource() before Vote::save()) will have to be updated to use the new parameter. Modules that use the default behavior will not have to change, but they will get different results when calling VoteStorage::getUserVotes() for anonymous users.

Data model changes

None. There is already a vote_source field in the database table.