example client-side javascript code to communicate with bettercap API

bcap.js

var session
var credentials
var resp

function encodeBasicAuthorizationCredentials(options = {}) {
  return 'Basic ' + btoa(options.username + ":" + options.password)
}

function setCredentials(options = {}) {
  credentials = encodeBasicAuthorizationCredentials(options)
}

function getSession() {
  fetch("/api/session", { method: 'GET', headers: { 'Authorization': credentials } })
  .then(function(response) {
    response.json().then(function(json) { session = json })
  });
}

function setSession(data) {
  var request = new Request("/api/session", {
    method: 'POST', 
    body: JSON.stringify(data), 
    headers: { 
      'Authorization': credentials
    } 
  });
  fetch(request).then(function(response) {
    response.json().then(function(json) { resp = json })
  });
}

setCredentials({ username: "bcap", password: "bcap" })

data = {"cmd":"net.probe on"}

setSession(data)