ES6 Deep Proxy

deep_proxy.js

const _ = require('lodash')
const protectCache = new Set()
const protect = (val) => {
  return new Proxy(val, {
    get: function (obj, prop) {
      // recursive
      const value = obj[prop]
      if ((_.isPlainObject(value) || Array.isArray(value)) && !protectCache.has(value)) {
        const result = protect(value)
        protectCache.add(result)
        return result
      }
      return obj[prop];
    },
    set: function (obj, prop, value) {
      // your actions here
      // ... ...
      if (Object.prototype.hasOwnProperty.call(obj, prop)) {
        console.warn('Blocked setter in variable protecter, the blocked prop is: ', prop)
      } else {
        obj[prop] = value
      }
      // always return true if you don't want to throw in strict mode
      return true
    },
    deleteProperty: function (obj, prop) {
      // your actions here
      // ... ...
      // always return true if you don't want to throw in strict mode
      console.warn('Blocked delete action in variable protecter, the blocked prop is: ', prop)
      return true
    }
  })
}

// usage
const obj = protect({})
obj.hello = 1 // ok
obj.hello = 2 // blocked
obj.hello = 1 // blocked
delete obj.hello // blocked
delete obj['hello'] // blocked

obj.foo = { bar: 1 } // ok
obj.foo.bar = 2 // blocked