example_configs: Add Carpal (#916)

README.md

@@ -364,6 +364,7 @@ folder for help with:
 - [Authentik](example_configs/authentik.md)
 - [Bookstack](example_configs/bookstack.env.example)
 - [Calibre-Web](example_configs/calibre_web.md)
+- [Carpal](example_configs/carpal.md)
 - [Dell iDRAC](example_configs/dell_idrac.md)
 - [Dex](example_configs/dex_config.yml)
 - [Dokuwiki](example_configs/dokuwiki.md)

example_configs/carpal.md

@@ -0,0 +1,59 @@
+# Configuration for Carpal
+
+[Carpal](https://github.com/peeley/carpal) is a small, configurable
+[WebFinger](https://webfinger.net) server than can pull resource information
+from LDAP directories.
+
+There are two files used to configure Carpal for LDAP:
+
+- The YAML configuration file for Carpal itself
+- A Go template file for injecting the LDAP data into the WebFinger response
+
+### YAML File
+
+Replace the server URL, admin credentials, and domain for your server:
+
+```yaml
+# /etc/carpal/config.yml
+
+driver: ldap
+ldap:
+  url: ldap://myldapserver
+  bind_user: uid=myadmin,ou=people,dc=foobar,dc=com
+  bind_pass: myadminpassword
+  basedn: ou=people,dc=foobar,dc=com
+  filter: (uid=*)
+  user_attr: uid
+  attributes:
+    - uid
+    - mail
+    - cn
+  template: /etc/carpal/ldap.gotempl
+```
+
+If you have configured any user-defined attributes on your users, you can also
+add those to the `attributes` field.
+
+### Go Template File
+
+This is an example template; the template file is intended to be editable for
+your needs. If your users, for example, don't have Mastodon profiles, you can
+delete the Mastodon alias.
+
+```gotempl
+# /etc/carpal/ldap.gotempl
+
+aliases:
+  - "mailto:{{ index . "mail" }}"
+  - "https://mastodon/{{ index . "uid" }}"
+properties:
+  'http://webfinger.example/ns/name': '{{ index . "cn" }}'
+links:
+  - rel: "http://webfinger.example/rel/profile-page"
+    href: "https://www.example.com/~{{ index . "uid" }}/"
+```
+
+This example also only contains the default attributes present on all LLDAP
+users. If you have added custom user-defined attributes to your users and added
+them to the `attributes` field of the YAML config file, you can use them in
+this template file.