Question

For example suppose I have the following

app.get('/', function(req, res) {
    var ip;
    if(req.headers['x-forwarded-for']){
        ip = req.headers['x-forwarded-for'];
    }
    else {
        ip = req.connection.remoteAddress;
    }
});

I would like to unit test to see whether ip is being properly retrieved. One way is as follows

function getIp(req) {
    var ip;
    if(req.headers['x-forwarded-for']){
        ip = req.headers['x-forwarded-for'];
    }
    else {
        ip = req.connection.remoteAddress;
    }
    return ip;
}

app.get('/', function(req, res) {
    var ip = getIp(req);
});

Now I have a function getIp that I can unit test. However I’m still stuck. How can I feed a simulated req object into getIp?

Answer 1

I would just write integration-tests for that. Node.js is fast enough for that. Especially when you use something like Mocha’s watch-mode. You could use something like superagent or request to perform http requests.

There is also something like for example nock to mock out your http requests. Although I have never used it because integration-tests test the real thing and are fast enough for my tast.