Discount for reposting through the site?

Question

JavaScript

Is it possible to make it so that when adding a certain post to the wall, give the user some kind of discount? I followed the example:

$('.getbonus').on('click', function(){
                if (!$(this).hasClass('disabled')){
                    var message = $(this).attr("data-message");
                    hClick(message);
                }
            })

            function hClick(message) { // обработчик нажатия
                VK.Api.call('wall.post', {
                    message:message,
                    attachments:"https://site.ru"
                }, hPost); 
            }

            function hPost(r) { // обработчик окончания выполнения API запроса
                if(!r) throw "Bad response from VK";
                if( r.error) { // если отказался постить
                    console.log("Not posted. Error:", r.error);
                } else if( r.response) {
                    if( r.response.post_id) { // это id свежесозданного поста
                        console.log("Posted with id ", r.response.post_id);
                        console.log("Скидка получена", r.id);
                    } else {
                        console.log("No post id, no idea why", r);
                    }
                } else {
                    console.log("Not posted, no idea why", r);
                }
            }

But this only works for me, apparently for the owner of the group, etc. Is it possible to make any user be able to repost?

Answer 1

https://vk.com/dev/share_details
https://vk.com/dev/objects/post
To read the wall, you need to authorize the user through vk with the appropriate permissions, since you need to know the user uid
https://vk.com/ dev/access_token

Answer 2

Simple option: Add a parameter to the link, and give a discount on the first transition from the repost to the site.