Development of UserDirectory plugin

Questions/Notes

• Currently, all Trac code still uses env.get_known_users() method - should they use the plugin directly (and env.userdir to get the providers), just like that method in env does? If so, the method in env goes away.
• In working on the limit parameter, I'm wondering if we also need a page parameter, to page thru the users if there are a lot of them?
• restrict_owner doesn't work in the global trac.ini - should it? It would be nice for my multi-project setup.
• Is trac/userdir.py a good place for the interface and Trac plugin, or would somewhere else be a better fit?
• I didn't do very much with different attributes of users, so we'll need more work there, esp. when the LDAP plugins are developed.

Example of DSource UserDirectory plugin

class DSourceUserDirectory(Component):
    implements (IRequestHandler, IUserDirectory)
    
    # IRequestHandler methods

    def match_request(self, req):
        self.req = req
        return False

    def process_request(self, req):
        pass


    # IUserDirectory methods
    def get_known_user_info(self, cnx=None, limit=None):
        proj = get_project_code(self.req)
        cnx = get_db()
        cursor = cnx.cursor()
        cursor.execute("SELECT username, user_email "
                       "FROM phpbb_users u " 
                       " INNER JOIN members_projects mp on u.user_id=mp.member_id "
                       " INNER JOIN projects p on mp.project_id=p.project_id "
                       "WHERE project_code=%s "
                       "ORDER BY username", (proj,))
        
        for username,email in cursor:
            yield username,username,email

    def get_known_users(self, cnx=None, limit=None):
        proj = get_project_code(self.req)
        cnx = get_db()
        cursor = cnx.cursor()
        cursor.execute("SELECT username "
                       "FROM phpbb_users u " 
                       " INNER JOIN members_projects mp on u.user_id=mp.member_id "
                       " INNER JOIN projects p on mp.project_id=p.project_id "
                       "WHERE project_code=%s "
                       "ORDER BY username", (proj,))
        
        for username in cursor:
            yield username[0]

    def get_user_attribute(self, user, attr):
        pass
    
    def get_supported_attributes(self):
        pass