Why I have to send params as an object in $http angular?

Question

I'm making CRUD and if I want to send some data to my backend (node.js) then I receive an error: angular.js:10765 POST http://localhost:1234/shop/removeProduct/574bf938b16158b40f9c87bc 400 (Bad Request)

script:

$scope.removeProduct = function (partnerId, productId) {
    $http.post("/campaign/removeProduct/" + partnerId, productId);
}

The solution is just simply pack this parameter (productId) in an object like this:

$scope.removeProduct = function (partnerId, productId) {
    $scope.productData = {productId: productId};
    $http.post("/campaign/removeProduct/" + partnerId, $scope.productData);
}

But why I have to do this like this? By the way, is this correct or should I do it in a different way?

---

@EDIT One more thing, how should i refresh data after I added/removed any object? Is this correct?

$scope.addPartner = function(data) {
$http({method: 'POST', url: addPartner, data})
.then(function(response) {
console.log(response);
});
$scope.loadPartnersData();
window.alert("Partner added!");
};

$scope.loadPartnersData = function () {
$http.get("/campaign/partner-list").then(function(result) {
$scope.partnerList = result.data.partnerList;
});
};

backend:

router.get('/partner-list', function (req, res) {
    Partner.find({}, function (err, partnerList) {
        if (err) throw err;

        res.json({ partnerList: partnerList });
    });
});

Answer 1

I'm assuming you want the url to be something like /shop/removeProduct/34523543?productData=5325345. If so then I would use the angular way of declaring $http request:

var url = '/shop/removeProduct/' + partnerId; /* How ever you declare this */
$scope.removeProduct = function() {
  $http({method: 'POST', url, params:{'productData': productId}})
    .then(function(response) {
      console.log(response);
    });
};

$scope.removeProduct();

Angular then takes care of the decoding of the parameters