I'm trying to embed dhis2 map to my web application but I am facing an issue which says DHIS is not not define. Please can anyone help me to solve this? Here is the code:

var base = "server.com";
 $(document).ready(function(){
    Ext.onReady( function() {
        Ext.Ajax.request({
        url: base + "dhis-web-commons/security/login.action",
        method: "POST",
         params: { j_username: "my_username", j_password: "my_password" },
         headers:{'Content-Type': 'application/json'},
         success: setLinks,
         failure: function(response) {
             console.log("logged in failed, try again later");
         }
        });
      });
 })
function setLinks(){
    DHIS.getMap({ url: base, el: "map1", id: "map_id" });
}```