Publicize: use get_the_excerpt() and the_content filter when building og:description

[snarfed]

hi! right now, when og:description comes from the post excerpt or content, it pulls them directly from the db, bypassing plugins that otherwise modify them via filter and hooks. this can be a problem for sites that depend on those modifications.

Steps to reproduce the issue

as an example, i author and store post content in markdown, and use a plugin to render that to HTML. jetpack currently puts the raw markdown content directly into og:description. e.g. with this post content:

I talked with [Sally](http://sally.com/) recently...

What I expected

I expected the post content to be rendered, then HTML tags stripped, resulting in:

<meta property="og:description" content="I talked with Sally recently...

What happened instead

instead, the raw markdown link syntax surfaced in og:description:

<meta property="og:description" content="I talked with [Sally]( recently...

...and ultimately also in the facebook preview and twitter card. :/

[snarfed]

the patch below fixes this for me. it's currently up and running on https://snarfed.org/ . i'm putting together a PR, but i wanted to give you all a heads up and check that this sounds ok first. thanks in advance!

@@ -100,10 +104,11 @@ function jetpack_og_tags() {

  $tags['og:url']         = get_permalink( $data->ID );
  if ( ! post_password_required() ) {
-     if ( ! empty( $data->post_excerpt ) ) {
-         $tags['og:description'] = preg_replace( '@https?://[\S]+@', '', strip_shortcodes( wp_kses( $data->post_excerpt, array() ) ) );
+     $excerpt = get_the_excerpt( $data );
+     if ( ! empty( $excerpt ) ) {
+         $tags['og:description'] = preg_replace( '@https?://[\S]+@', '', strip_shortcodes( wp_kses( $excerpt, array() ) ) );
      } else {
-         $exploded_content_on_more_tag = explode( '<!--more-->', $data->post_content );
+         $exploded_content_on_more_tag = explode( '<!--more-->', apply_filters( 'the_content', $data->post_content ) );
          $tags['og:description'] = wp_trim_words( preg_replace( '@https?://[\S]+@', '', strip_shortcodes( wp_kses( $exploded_content_on_more_tag[0], array() ) ) ) );
      }
  }

[jeherve]

Related: #2899

[snarfed]

fwiw, i briefly looked at a couple other markdown plugins just now that work the same way, ie store raw markdown in post_content and render it dynamically, and they both suffer from the same problem:

• https://wordpress.org/plugins/parsedown-wp/
• https://wordpress.org/plugins/wp-parsedown/

[stale[bot]]

This issue has been marked as stale. This happened because:

• It has been inactive in the past 6 months.
• It hasn’t been labeled `[Pri] Blocker`, `[Pri] High`.

No further action is needed. But it's worth checking if this ticket has clear reproduction steps and it is still reproducible. Feel free to close this issue if you think it's not valid anymore — if you do, please add a brief explanation.