declare route parameters for exporess router code example

Example 1: node js express url parameters

// http://localhost:8080/api/1
app.get('/api/:version', function(req, res) {
    res.send(req.params.version);
});

Example 2: express route parameters

Route path: /flights/:from-:to
Request URL: http://localhost:3000/flights/LAX-SFO
req.params: { "from": "LAX", "to": "SFO" }