Difficulty executing bookmarklet javascript -

i'm trying create bookmarklet app parses information amazon, etsy, , jcrew , transmits wishlist application built in rails. i've succeeded in creating bookmark button loads javascript file dom, not seem executing correctly , passing data app. or maybe javascript faulty. can me figure out i'm doing wrong? i've included js file below:

function() {  function get_amazon_product_info()      {         var title_span = document.getelementbyid("btasintitle");         var title = title_span.innertext;          var image_tag = document.getelementbyid("main-image");         var image = image_tag.getattribute("src");          var price_span = document.getelementbyid("actualpricevalue");         var price = price_span.innertext;          var product_info = {             title: title,             image: image,             price: price         }         return product_info     }  function get_etsy_product_info() {         var title_span = document.getelementbyid("item-title");         var title = title_span.innertext;          var image_div = document.getelementbyid("fullimage_link1");         var image_tag = image_div.getelementsbytagname("img");         var image = image_tag[0].getattribute("src");          var price_div = document.getelementsbyclassname("item-price");         var price_span = price_div[0].getelementsbyclassname("currency-value")         var price = price_span[0].innertext;          var product_info = {             title: title,             image: image,             price: price         }         return product_info }  function get_jcrew_product_info() {     var title_span = document.getelementbyid("pdp-title");         var title = title_span.innertext;          var image_div = document.getelementsbyclassname("prod_main_img");         var image_tag = image_div[0].getelementsbytagname("img");         var image = image_tag[0].getattribute("src");          //lame implementation -- need able determine radio button checked. finish later!          var price_div = document.getelementsbyclassname("pdp-shapes");         var price_span = price_div[0].getelementsbyclassname("price")         var price = price_span[0].innertext;          var product_info = {             title: title,             image: image,             price: price         }         return product_info }  function determine_params()  {         domain = document.domain;         if (domain == 'www.amazon.com')         {                get_amazon_product_info();         }         else if (domain == 'www.etsy.com')         {             get_etsy_product_info();         }         else if (domain == 'www.jcrew.com')         {             get_jcrew_product_info();         } }     function send_data(product_info) {                var link_url = document.url;     var http = new xmlhttprequest();     var url = "http://max-miller.local:3000/add_product";     var params = "title=" + product_info[title] + "&image=" + product_info[image] + "&price=" + product_info[price] + "&link_url=" + link_url;     http.open("post", url , true);      //send proper header information along request     http.setrequestheader("content-type", "application/x-www-form-urlencoded");     http.setrequestheader("content-length", params.length);     http.setrequestheader("connection", "close");      http.onreadystatechange = function() {         if(http.readystate == 4 && http.status == 200) {             alert(http.responsetext);         }     }      http.send(params); }  determine_params(); send_data(product_info); 

}

as noted in comments, there 2 problems see code as-is.

first, closure never executed - it's syntactically incorrect as-is. in browser's console, it's difference between example:

function() { console.log('something'); } 

and one:

(function() { console.log('something'); })(); 

second, xmlhttprequest work within context of page's domain. (the script doesn't receive special privileges domain comes.) so, given nature of script, looks max-miller.local:3000 not intended domain-of-execution, , request fail.

look jsonp-like solutions.