module.exports how to return a function value?

answer.md

The return value of getAOLDataCount is undefined. You're returning the aolCount variable from within an anonymous function in your .then() call and it's not being returned.

It's basically the same as this:

module.exports = {
    getAOLDataCount:  function () {
        wd = new WeeklyData(sequelize, Sequelize.DataTypes);
        wd.count({where: {week:201740, project: 8}}).then(function (aolCount) {
            console.log(aolCount);
            return aolCount;
        });
        return undefined;
    }
};

Since, wd.count is asynchronous you cannot return aolCount this way, you will have to restructure your code.

Consider this approach (though there are many you could take) which passes the response object to your module which then can call .send().

app.js

app.get('/sample', function (req, res, next) {
   aol.getAOLDataCount(res);
});

aol.js

module.exports = {
    getAOLDataCount:  function (res) {
        wd = new WeeklyData(sequelize, Sequelize.DataTypes);
        wd.count({where: {week:201740, project: 8}}).then(function (aolCount) {
            console.log(aolCount);
            res.send(aolCount);
        });
    }
};

Thank you. This is a brilliant explanation and has really helped my understanding of Async functions.

Hi @simonjcarr, no problem, glad to help!