Nrthugu

I'm working with express and node.js application. I have a regular router, which:

• finds myID in DB,


• if myID exists it tries to addVisit()
  


• if error occures (may such table doesn't exist) it catches the error, creates the new table and addVisit() to it.

The router code is below:

    router.get('/:myId', errorHandler(async (req, res, next) => {



    console.log(req.params.myId + ' This is myID Params!');



    const Domain = DomainModel(db, Sequelize);

    const Click = ClickModel(db, `${req.params.myId}_clicks`, Sequelize);



    try {

        let row = await Domain.findOne({ where: { myId: req.params.myId } });



        console.log(row.myId + ' This is myID from DB');



        if (row.myId) {

            try {

                await addVisit(Click, req);

                res.sendStatus(200);

            } catch (err) {

                console.log(`This error fires!`);

                if (err.message !== `Validation error`) {

                    try {

                        await db.sync();

                        await addVisit(Click, req);

                        res.sendStatus(200);

                    } catch (err) {

                        console.log(err);

                        res.sendStatus(400);

                    }

                } else {

                    res.sendStatus(400);

                }

            }

        } else {

            console.log(`No such myId in use`);

            res.sendStatus(400);

        }

    } catch (err) {

        console.log(err);

    }

})

But the code runs twice! My console.log() shows:

1. ==> 1231231231 This is myID Params!

2. ==> 1231231231 This is myID from DB

3. ==> This error fires!

4. ==> favicon.ico This is myID Params!

5. ==> TypeError: Cannot read property 'myID' of null

If I comment this part of code it runs only one time!

// if (err.message !== `Validation error`) {

//    try {

//        await db.sync();

//        await addVisit(Click, req);

//        res.sendStatus(200);

//    } catch (err) {

//        console.log(err);

//        res.sendStatus(400);

//    }

// } else {

//    res.sendStatus(400);

// }

This is the only place where I use console.log()! This is the simple sample project in which I able to reproduce the behavior. So why does the code runs twice and WHY my params.myID became favicon.ico?

Whenever you open a webpage, there is a small icon in the upper left corner of the tab, containing the logo of the page. That icon gets loaded from theserver/favicon.ico, if that returns an error the icon stays empty, otherwise the photo returned by that is used as the icon. There are other such reserved files, such as norobots.txt and manifest.json. Therefore it is a bad idea to have the variable url part at the main level. This one:

 router.get('/:myId'

catches everything. Instead you should move it to a subpath:

 router.get('/id/:myId'

Because with route param /:myId you will serve /favicon request too. So those are the 2 requests.