BodyParser Behavior

I am sending a POST request with cURL :

curl http://tarvos.local:8080/partial_Users/2 -d '{currentPage : 1, firstID : 53d62fc6642aecf45c8b456f }'

In my NodeJS application, the request goes through the bodyParser.json() middleware. I have another middleware that processes the request :

app.post('/partial_Users/:page', function(req, res, next) {

    var destinationPage = req.params.page;
    var currentPage = req.body.currentPage;
    var firstID = req.body.firstID;
    console.log(req.body)
    console.log(''+ currentPage + firstID)
    [...]
}

In this situation, I would expect req.body.currentPage to return 1. In fact, it returns 'undefined'.

I have noticed that when I do a console.log(req.body), I get the following string :

{ '{currentPage : 1, firstID : 53d62fc6642aecf45c8b456f }': '' }

It becomes apparent now that req.body.currentPage would return undefined. For some reason, bodyParser is not parsing JSON properly. The same behaviour is seen for thereq.body.firstID.

Either I am not using BodyParser properly, or my JSON request in not structured properly maybe?