Automatic Open Graph meta tags for posts

[noraj]

Please make sure these boxes are checked before submitting your issue. Thank you!

• [x] I have setuped and configurated the blog according to Hexo official documentation;
• [x] I have read the Theme Wiki carefully and created my own configuration file(_config.yml);
• [x] I have looked up the Issues and found no duplicate issues.

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Description

It would be nice to have the following Open Graph meta tags automatically generated for each article (post).

<meta property="og:title" content="European Travel Destinations">
<meta property="og:description" content="Offering tour packages for individuals or groups.">
<meta property="og:image" content="http://euro-travel-example.com/thumbnail.jpg">
<meta property="og:url" content="http://euro-travel-example.com/index.htm">
<meta property="og:site_name" content="European Travel, Inc.">

• og:title from the title of the post
• (Optional) og:description like an excerpt from the X first chars of the post
• og:image from the thumbnail front-matter
• og:url from the post permanent URL
• og:site_name from the site _config.yml title

This is independent from https://github.com/ppoffice/hexo-theme-hueman/wiki/Miscellaneous#open-graph

[noraj]

It seems that it is already the case (Idk if it's hexo or the theme).

For this article https://rawsec.ml/en/archlinux-kalu/ I have

<meta property="og:type" content="article">
<meta property="og:title" content="Kalu - Keeping ArchLinux Up-to-date">
<meta property="og:url" content="https://rawsec.ml/en/archlinux-kalu/index.html">
<meta property="og:site_name" content="Rawsec">
<meta property="og:description" content="Intro# Basically updating ArchLinux is as easy as running pacman -Syu. But blindly running pacman -Syu everyday is not necessarily a good idea. Sometimes some updates require manual intervention, so y">
<meta property="og:locale" content="en_US">
<meta property="og:image" content="https://rawsec.ml/images/archlinux.svg">