Create database for test with mocha

Question

whats up?

I have this struct in my project: https://i.stack.imgur.com/kKmkw.jpg

I have the file database.js which is some connection methods. (https://github.com/viniciusmurad/genericProject-node/blob/master/config/database.js)

In my server.js file I have a request from the database.

require('./config/database')('localhost/generic');

My question:

I'm wanting to create an auxiliary database for testing. I'm using gulp task to start mocha

gulp.task('test', function() {
    env({vars: {ENV:'Test'}});
    gulp.src('test/*.js', {read: false})
        .pipe(gulpMocha({reporter: 'nyan' }))
})

I thought of something:

var db;
if(process.env.ENV == 'Test') {
    db = mongoose.connect('localhost/generic_test');
}
else {
    db = mongoose.connect('localhost/generic');
} 

But where should I put the above function in accordance with the structure of my project?

Thankss