view mod_ogp/README.markdown @ 4931:13070c6a7ce8

mod_http_muc_log: Fix exception on lack of trailing slash in room path A request to /room leads to the match call returning nil which in turn calls nodeprep(nil). In Prosody 0.11.x this does nothing and simply returns the nil, while in 0.12 it is an error. Now it redirects to the calendar view at /room/ - even for non-existant rooms. Discovered at a deployment with http_paths = { muc_log = "/" } and requests to /robots.txt and similar, which now result in a uses redirect before returning 404.
author Kim Alvefur <zash@zash.se>
date Fri, 22 Apr 2022 14:29:32 +0200
parents 09f0911c735d
children
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# 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" }
```