Open Graph

Planted: Dec 2021

Tended: Feb 2022

Status: decay

The Open Graph protocol enables a web page to become a rich object in a social graph. Some sites that allow posting (like Facebook), use this protocol (or a variation of it) to display an image and other meta information about a web page when a URL is added to the post. Example of a rich object on Twitter:

A twitter post featuring a wireframe of a sphere.

Common Open Graph HTML elements required on the web page to enable this:

/index.html

<!DOCTYPE html>
<html lang="en">
   <head>
      <meta
         property="og:type"
         content="article" />
      <meta
         property="og:url"
         content="https://garden.bradwoods.io/notes/global-state" />
      <meta
         property="og:site_name"
         content="Brad Woods' digital garden" />

      <meta
         property="og:title"
         content="Global State in Next.js using XState" />
      <meta
         property="og:description"
         content="How to create global state in Next.js using XState" />

      <meta
         property="og:image"
         content="https://garden.bradwoods.io/ogImages/globalState.png" />
      <meta
         property="og:image:height"
         content="627" />
      <meta
         property="og:image:width"
         content="1200" />
      <meta
         property="og:image:alt"
         content="A wireframe of a sphere." />

      <!-- date format: ISO 8601 international standard -->
      <meta
         property="article:published_time"
         content="2021-05-23T10:00:00+10:00" />
      <meta
         property="article:modified_time"
         content="2021-11-11T11:00:00+11:00" />
      ...

Twitter

Elements required to render a Twitter Card when sharing a web page on Twitter post:

/index.html

<!DOCTYPE html>
<html lang="en">
   <head>
      <!-- content can be "summary" or "summary_large_image" -->
      <meta
         name="twitter:card"
         content="summary_large_image" />
      <meta
         name="twitter:url"
         content="https://garden.bradwoods.io/notes/global-state" />
      <meta
         name="twitter:title"
         content="Global State in Next.js using XState" />
      <meta
         name="twitter:description"
         content="How to create global state in Next.js using XState." />
      <meta
         name="twitter:creator"
         content="@bradwoodsio" />
      <meta
         name="twitter:image"
         content="https://garden.bradwoods.io/ogImages/globalState.png" />
      <meta
         name="twitter:image:alt"
         content="How to create global state in Next.js using XState." />
      ...

Elements required to render a share card when sharing a web page in a LinkedIn post:

/index.html

<!DOCTYPE html>
<html lang="en">
   <head>
      <meta
         property="og:url"
         content="https://garden.bradwoods.io/notes/global-state" />
      <meta
         property="og:title"
         content="Global State in Next.js using XState" />
      <meta
         property="og:description"
         content="How to create global state in Next.js using XState." />
      <meta
         property="og:image"
         content="https://garden.bradwoods.io/ogImages/globalState.png" />
      ..

Publish date

For a LinkedIn post to register a publish date, a time element needs to be on the page with a datetime attribute. Its value needs to be in ISO 8601 format.

/index.html

<!DOCTYPE html>
<html lang="en">
   ...
   <body>
      <time datetime="2021-12-10T11:00:00+11:00">Dec 2021</time>
      ...

To convert a date into this format, use .toISOString():

index.js

const date = "2020-07-04";
const formatted = new Date(date).toISOString();
console.log(formatted);

A vertical and horizontal line with arrows on each end.

Image Size

Twitter's documentation details minimum and maximum image size but doesn't recommend a size or aspect ratio (for either summary or summary_large_image). Twitter's card displays a summary_large_image image at 504 x 264px (1.91:1 ratio) on desktop. The only recommendation I could find was from Neil Patel who recommends 1200 x 627px (1.91:1 ratio). This is consistent with LinkedIn's share image recommendation. The displayed image size doesn't adapt if an image with a different ratio is provided, even with accurate og:image:height og:image:height values.

A Twitter 1200 x 600px share image (cut-off at the sides):

A LinkedIn 1200 x 600px share image (cut-off at the sides):

A LinkedIn post featuring a wireframe of a sphere.

A Twitter 1200 x 627px share image (not cut-off):

Design

It's common to see meta information, such as the page title, within a share image. Considering most platforms will display meta information along with the image when sharing, I think this approach is duplicating information, resulting in poor UX (User Experience).