Get Record ID from lighting:recordForm

Lightning Component :

<aura:component >   
    <div class="slds-box slds-theme_default">  
          
        <lightning:recordForm  objectApiName = "Opportunity"  
                               layoutType = "Full"   
                               columns = "2"  
                               onsuccess = "{! c.handleSuccess }"/>  
              
    </div>  
</aura:component> 

Apex :

({   
    handleSuccess : function(component, event, helper) {   
        var params = event.getParams();  
        alert(params.id);   
    }    
})