text: import React from 'react'
  import Helmet from 'react-helmet'
  
  const Head = ({ title, description, url, image }) => (
    <div>
      <Helmet>
        <title>{title}</title>
        <meta name="description" content={description} />
        <meta property="og:url" content={url} />
        <meta property="og:title" content={title} />
        <meta property="og:description" content={description} />
        <meta property="og:image" content={image} />
      </Helmet>
    </div>
  )
  
  Head.defaultProps = {
    title: 'Gatsby Bootstrap 4 Starter',
    description: 'Gatsby Bootstrap 4 Starter',
    url: 'http://example.com',
    image: 'http://example.com/image.jpg'
  }
  
  export default Head
  