custom metadata type not pulling the values in lightning.

hi all, 

we are implementing custom component common links in the record page where every user can hit the link navigate to a different page instantly.  For that i created the cutom metadata type store the urls in cutom meta data type . but not working though as of now . 

here is the code snippet

apex clas:

public with sharing class CustomPSALinks {      @AuraEnabled      public static List <PSA_Links__mdt> getPSALinks()      {     return([Select id,MasterLabel,Long_URL__c from PSA_Links__mdt]);           } }

({ doInit: function(component, event, helper) {       component.set('v.mycolumns', [             {label: 'Label', fieldName: 'MasterLabel', type: 'text'},                 {label: 'Long Url', fieldName: 'Long_URL__c', type: 'URL'}             ]);      var action = component.get("c.getPSALinks");          action.setParams({         });     action.setCallback(this, function(response){   var results = response.getReturnValue();   alert (results);      var state = response.getState();   if (state === "SUCCESS") {            var label =      results.MasterLabel;         console.log( response.getReturnValue());              alert(label);   component.set('v.psalinks', label);          } });         $A.enqueueAction(action);     } })

<aura:component implements = "flexipage:availableForAllPageTypes,force:appHostable" controller = "CustomPSALinks" >        <aura:handler name="init" value="{!this}" action="{!c.doInit}"/>        <aura:attribute name="psalinks" type="PSA_Links__mdt[]" default="" />       <aura:attribute name="mycolumns" type="List"/>          <div class="slds-p-around_medium" style="background-color:white;">     <b>PSA Links</b>       <br></br>                  <lightning:formattedUrl  value = "{!v.psalinks.Long_URL__c}" label = "{!v.psalinks.MasterLabel}" />       </div>     </aura:component>