extract domain from json and url

index.js

const data1 = {
  attributes: {
    domain: 'from.attributes.com'
  }
}

const data2 = {
  attributes: {
    unknownAttributes: {
      domain: 'from.unknownAttributes.com'
    },
    url:
      'https://www.amazon.com/Zinus-SmartBase-Foundation-Replacement-Noise-Free/dp/B01GHHIWFO/ref=sr_1_1/146-9491966-1844353?ie=UTF8&qid=1521436930&sr=8-1&keywords=841550091137'
  }
}

const data3 = {
  attributes: {
    url:
      'https://www.fromurl.com/Zinus-SmartBase-Foundation-Replacement-Noise-Free/dp/B01GHHIWFO/ref=sr_1_1/146-9491966-1844353?ie=UTF8&qid=1521436930&sr=8-1&keywords=841550091137'
  }
}

function getDomain(attributes) {
  if (!attributes) {
    return null
  }

  if (attributes) {
    if (attributes.domain) {
      return attributes.domain
    }
    const unknownAttributes = attributes.unknownAttributes
    if (unknownAttributes) {
      if (unknownAttributes.domain) {
        return unknownAttributes.domain
      }
    }
    const url = attributes.url
    if (url) {
      let parts
      if (url.search(/^https?\:\/\//) != -1) {
        parts = url.match(/^https?\:\/\/([^\/?#]+)(?:[\/?#]|$)/i, '')
      } else {
        parts = url.match(/^([^\/?#]+)(?:[\/?#]|$)/i, '')
      }
      return parts[1]
    }
  }
}

console.log(getDomain(null))
console.log(getDomain(undefined))

console.log(getDomain(data1.attributes))

console.log(getDomain(data2.attributes))

console.log(getDomain(data3.attributes))