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--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/mod_ogp/README.md	Tue Oct 22 10:26:01 2024 +0200
@@ -0,0 +1,32 @@
+# 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:
+
+```xml
+<message id="example" from="chatroom@muc.example.org" to="user@chat.example.org/resource">
+<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/
+
+Configuration
+-------------
+
+You can present an allowlist or denylist of domains for which OGP metadata will be fetched
+via the `ogp_domain_allowlist` and `ogp_domain_denylist` settings repectively.
+
+For example:
+
+```lua
+Component "muc.example.org" "muc"
+  modules_enabled = { "ogp" }
+  ogp_domain_allowlist = { "prosody.im" }
+```