If I understand correctly, you are trying to visually format the object that came out of a JSON.
For the formatting you want you can:
- Call the 
Stringify with a specific spacing 
- Cut the first and last character with 
slice(1,-1) 
- Use the label 
<pre> to keep formatting in html 
Example:
var obj = {
  "arvore": "/",
  "avo": "obadias",
  "pai": {
    "eu": "Leonardo"
  }
}
class Access {
  static getRaiz(obj) {
    //4 é o numero de espaços que cada objeto anda para dentro
    return JSON.stringify(obj, undefined, 4); 
  }
}
//aqui utiliza o <pre> no inicio e o slice para cortar primeiro e ultimo
document.body.innerHTML = '<pre>' + Access.getRaiz(obj).slice(1,-1) + '</pre>';
 
 
With string interpolation could build html as follows:
document.body.innerHTML = `<pre>${Access.getRaiz(obj).slice(1,-1)}</pre>`;
This second way ends up simplifying a lot when you have to include many expressions in a String.