code: function authenticateAgainstProvider(pool, connection, providers, cb) {
      // Finished re-authenticating against providers
      if (providers.length === 0) return cb();
      // Get the provider name
      var provider = pool.authProviders[providers.pop()];
  
      // Auth provider
      provider.reauthenticate(write(pool), [connection], function(err) {
        // We got an error return immediately
        if (err) return cb(err);
        // Continue authenticating the connection
        authenticateAgainstProvider(pool, connection, providers, cb);
      });
    }
docs: Authenticate