open graph Meta Tags in Vue JS don't show image

Question

I design a blog and I would like that when sharing to social networks, the preview image displays like in Medium's posts

<meta property="og:image" content="https://medium.com/js-dojo/getting-your-head-around-vue-js-scoped-slots-281bf82a1e4e"/>

I using vuejs2 with webpack and vue-meta to change the dynamic image of my post. But for Facebook, there don't working even when I put them in index.html.

I find this article on medium where it is said that it is necessary to use Server Side Rendered, but it is not said how to migrate from a totally designed project with a basic configuration (without SSR) to a project solving the problem. already the architecture is different and I have no reference

here is my code vue-meta

metaInfo () {
  return {
    title: '41devs | blog',
    titleTemplate: '%s - le titre',
    meta: [
      {name: 'viewport', content: 'user-scalable=no'},
      {property: 'og:title', content: 'title'},
      {property: 'og:type', content: 'article'},
      {property: 'og:url', content: 'http://c5e3b0ec.ngrok.io/blog/s'},// here it is just ngrok for my test
      {property: 'og:description', content: 'description'},
      {property: 'og:image', content: 'https://firebasestorage.googleapis.com/v0/b/dev-blog-2503f.appspot.com/o/postsStorage%2F-KxXdvvLqDHBcxdUfLgn%2Fonfleck?alt=media&token=24a9bf5b-dce2-46e8-b175-fb63f7501c98'},
      {property: 'twitter:image:src', content: 'https://firebasestorage.googleapis.com/v0/b/dev-blog-2503f.appspot.com/o/postsStorage%2F-KxXdvvLqDHBcxdUfLgn%2Fonfleck?alt=media&token=24a9bf5b-dce2-46e8-b175-fb63f7501c98'},
      {property: 'og:image:width', content: '1000'},
      {property: 'og:site_name', content: '41devs | blog'}
    ]
  }
}

Answer 1

When Facebook checks your page to find the meta data, they don't run your Javascript. Vue never runs, your tags are never replaced. This is a limitation of Facebook's crawler.

This means you would indeed have to render those tags at the server level, whether by Vue's server side rendering or by some other method (I don't know what type of server you are running). But yes, ultimately, you must be able to hard-code this value into your server response, otherwise it won't display in Facebook.

Answer 2

The way I handled this was to create some middleware that parses the URL path and dynamically updates the meta tags with the Cheerio module.

File for OG meta tag info:

const products = [
  {
    id: 111111111,
    title: 'Corporate Fat Cat',
    ogImage: 'https://cdn.com/corporate.jpg',
    description: 'The fat cats in Washington don’t even look this good'
  },
  {
    id: 222222222,
    title: 'Gangsta Cat',
    ogImage: 'https://cdn.com/gangsta.jpg',
    description: 'That’s how we roll'
  },
  {
    id: 333333333,
    title: 'Mechanic Cat',
    ogImage: 'https://cdn.com/mechanic.jpg',
    description: 'I have no idea what I’m doing.'
  }
];

Middleware:

app.use('/*', (req, res, next) => {
  if (/^\/api\//.test(req.originalUrl)) next();
  else if (/\/item\//.test(req.originalUrl)) updateMetaTags(req, res);
  else res.sendFile(`${__dirname}/client/dist/index.html`);
});

updateMetaTags function:

async function updateMetaTags(req, res) {

  // Get and parse products array from app src
  const productsSrc = `${__dirname}/client/src/products.js`;
  const productsText = await fs.promises.readFile(productsSrc);
  const productsArr = JSON.parse(productsText);

  // Retrieve product object that includes the current URL item id
  const productID = (req.originalUrl.match(/\d{9}/) || [])[0];
  const productObj = productsArr.find(prod => prod.id == productID);

  // Update the meta tag properties in the built bundle w/ Cheerio
  const baseSrc = `${__dirname}/client//dist/index.html`;
  const baseHTML = await fs.promises.readFile(baseSrc);
  const $base = $(baseHTML);
  const $url = $base.find('meta[property=og\\:url]');
  const $title = $base.find('meta[property=og\\:title]');
  const $image = $base.find('meta[property=og\\:image]');
  $desc = $base.find('meta[property=og\\:description]');

  $url.attr('content', `https://${req.get('host')}${req.originalUrl}`);
  $title.attr('content', productObj.title);
  $image.attr('content', productObj.ogImage);
  $desc.attr('content', productObj.description);

  // Send the modified HTML as the response
  res.send($.html($base));
}

I have this approached detailed more in this blog post.

Answer 3

Your title and titleTemplate has wrong structure.

return {
    title: 'Le titre',           // Set a current title of page
    titleTemplate: '%s - 41devs blog', // Name of your blog/website,
                                       // Title is now "Le titre - 41devs blog"
    meta: [ ...
    ]
}

It performed for best SEO in google https://support.google.com/webmasters/answer/79812?hl=en