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--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/mod_ogp/README.markdown	Mon Feb 22 17:51:51 2021 +0100
@@ -0,0 +1,18 @@
+# mod_ogp
+
+This module adds [Open Graph Protocol](https://ogp.me) metadata to URLs sent inside a MUC.
+
+With mod_ogp enabled, when a user sends a URL in a MUC (where the message has its `id` equal to its `origin-id`), the module calls the URL and parses the result for `<meta>` html tags that have any `og:...` properties.
+If it finds any, it sends a [XEP-0422 fastening](https://xmpp.org/extensions/xep-0422.html) applied to the original message that looks like:
+
+```
+    <message id="example" from="chatroom@chatservice.example" to="chatroom@chatservice.example">
+        <apply-to xmlns="urn:xmpp:fasten:0" id="origin-id-X">
+            <meta xmlns="http://www.w3.org/1999/xhtml" property="og:title" content="The Rock"/>
+            <meta xmlns="http://www.w3.org/1999/xhtml" property="og:url" content="https://www.imdb.com/title/tt0117500/"/>
+            <meta xmlns="http://www.w3.org/1999/xhtml" property="og:image" content="https://ia.media-imdb.com/images/rock.jpg"/>
+        </apply-to>
+    </message>
+```
+
+The module is intentionally simple in the sense that it is basically a transport for https://ogp.me/