Node, Mongoose - Can't access parent scope in query callback

问题

I'm a bit confused on why I am not seeing the parent scope inside a Mongoose Query Callback, here is my code:

var P = require('bluebird');

var getUser = P.promisify(
    function(userId, locals, next){

        logger.info(locals); //{offer: 1}

        User.findOne({_id: userId}).lean().exec(function(err, user){
            logger.info(locals); //undefined
            if(err){return next(err);}
            if(!locals)
                locals = {user: user};
            else{
                locals.user = user;
            }
            return next(null, locals);
        });
    }
);

var locals = {offer: 1};

getUser(user._id, locals);

I'm calling the getUser function with two params, in the function's scope I can see them both, but I need to access the locals variable inside the mongoose callback and not seeing the parent scope value in that scope.

Any idea on how to solve this?

Thanks in advance

来源：https://stackoverflow.com/questions/26969579/node-mongoose-cant-access-parent-scope-in-query-callback