Expressjs: Search query api

Question

I want to search through my user repository with a query string.

This should return all users with a similar username "kyogron" and similar email "kyogron@gmail"

GET localhost:3000/users?username=kyogron&[email protected]

This should return all users:

GET localhost:3000/users

I already managed to handle the routing parameters but I am stuck at optimizing it:

app.get('/users', function(req, res) {
    // creates a mongoosejs query object
    var query = User.find({});

    // to understand how expressjs handles queries:
    // ?username=kyogron&[email protected]
    // { username: "kyogron", email: "[email protected]" }
    //console.log(req.query);

    // this was one idea of optimizing the search query parameters
    // this doesn't work don't know why I always get an array of ALL users
    // even the key and value is right
    Object.keys(req.query).forEach(function(key) {
        query.select(key, req.query[key]);
    });

    // this was the way I was first handling the parameters, this works !!
    //if (req.query.username) query.where('username', req.query.username);
    //if (req.query.email) query.where('email', req.query.email);

    // the rest of the query
    query.select('username', 'email');
    query.exec(function(err, users) {
        if (err) throw err;
        res.json(users);
    });

});

These are the problems I am fighting with:

1. Why doesn't iterating the req.query object work?
2. How do I say mongoose to use a wildcard (e.g. kyo*)

Would be nice if somebody could help me out :)

Regards

EDIT:

The second issue would be solvable with $where:

    if (req.query.username) {
        query.$where(function() {
            return this.username === req.query.username; // here we need a regex check
        });
    }

Thos doesn't work... Could somebody give me a hint?

EDIT2:

Didn't managed anything with $where... however I now found

query.where('username').regex();

I just have to look for a searching regex which looks for similar words

EDIT3:

I found this thread: How to query MongoDB with "like"? I ask in the mongoosejs group how I could do this with mongoose

EDIT4:

if (req.query.username) {
            query.where('username').regex(new RegExp("\/"+req.query.username+"\/"));
}

I nearly got it. Just have to fix this stupid regex...

Answer 1

app.get('/users', function(req, res) {
    var query = User.find({});

    Object.keys(req.query).forEach(function(key) {
        query.where(key).regex(new RegExp(req.query[key]));
    });

    /*
    if (req.query.username) {
        query.where('username').regex(new RegExp(req.query.username));
    }
    if (req.query.email) {
        query.where('email').regex(new RegExp(req.query.email));
    }*/

    query.select('username', 'email');
    query.exec(function(err, users) {
        if (err) throw err;
        res.json(users);
    });

});

The first didn't work because I had a typo (.select() not .where()). The second was found in an extra thread

I am still a bit unsure about the chosen approach.

Iterating req.query would allow to make the code reusable (maybe as precondition routing parameter-function) but it is quite susceptible for errors