felt/static/admin.js

let adminToken = null;

async function doLogin() {
  const adminUsrInput = document.getElementById("input_admin_usr");
  const adminPassInput = document.getElementById("input_admin_pass");
  const errDiv = document.getElementById("loginErr");
  
  if (adminUsrInput && adminPassInput) {
    adminToken = await getAdminToken(adminUsrInput.value, adminPassInput.value);
    if (adminToken) {
      // render admin interface
    } else {
    if (errDiv) {
      errDiv.innerHTML = "Incorrect credentials";
    }
    }
  }
}

async function getAdminToken(user, pass) {
  const headers = new Headers();
  headers.set('Authorization', 'Basic ' + btoa(user + ":" + pass));
  try {
    const res = await fetch('/admin/api/auth/', {
      method: 'POST',
      headers: headers
    });
    
    if (res.ok) {
      return await res.json();
    }
    return null;
  } catch (err) {
    return null;
  }
}