Update AlertManager configuration section (#1182)

* docs/alerting: add tls_config for SMTP
* docs/alerting: update PagerDuty configuration
Signed-off-by: Simon Pasquier <spasquie@redhat.com>

content/docs/alerting/configuration.md

@@ -241,21 +241,32 @@ basic_auth:
 
 # Configures the TLS settings.
 tls_config:
-  # CA certificate to validate the server certificate with.
-  [ ca_file: <filepath> ]
-  # Certificate and key files for client cert authentication to the server.
-  [ cert_file: <filepath> ]
-  [ key_file: <filepath> ]
-  # ServerName extension to indicate the name of the server.
-  # http://tools.ietf.org/html/rfc4366#section-3.1
-  [ server_name: <string> ]
-  # Disable validation of the server certificate.
-  [ insecure_skip_verify: <boolean> | default = false]
+  [ <tls_config> ]
 
 # Optional proxy URL.
 [ proxy_url: <string> ]
 ```
 
+## `<tls_config>`
+
+A `tls_config` allows configuring TLS connections.
+
+```yaml
+# CA certificate to validate the server certificate with.
+[ ca_file: <filepath> ]
+
+# Certificate and key files for client cert authentication to the server.
+[ cert_file: <filepath> ]
+[ key_file: <filepath> ]
+
+# ServerName extension to indicate the name of the server.
+# http://tools.ietf.org/html/rfc4366#section-3.1
+[ server_name: <string> ]
+
+# Disable validation of the server certificate.
+[ insecure_skip_verify: <boolean> | default = false]
+```
+
 ## `<receiver>`
 
 Receiver is a named configuration of one or more notification integrations.
@@ -314,6 +325,10 @@ to: <tmpl_string>
 # The SMTP TLS requirement.
 [ require_tls: <bool> | default = global.smtp_require_tls ]
 
+# TLS configuration.
+tls_config:
+  [ <tls_config> ]
+
 # The HTML body of the email notification.
 [ html: <tmpl_string> | default = '{{ template "email.default.html" . }}' ]
 # The text body of the email notification.
@@ -393,10 +408,37 @@ service_key: <tmpl_secret>
   num_resolved: '{{ .Alerts.Resolved | len }}'
 } ]
 
+# Images to attach to the incident.
+images:
+  [ <image_config> ... ]
+
+# Links to attach to the incident.
+links:
+  [ <link_config> ... ]
+
 # The HTTP client's configuration.
 [ http_config: <http_config> | default = global.http_config ]
 ```
 
+### `<image_config>`
+
+The fields are documented in the [PagerDuty API documentation](https://v2.developer.pagerduty.com/v2/docs/send-an-event-events-api-v2#section-the-images-property).
+
+```yaml
+source: <tmpl_string>
+alt: <tmpl_string>
+text: <tmpl_string>
+```
+
+### `<link_config>`
+
+The fields are documented in the [PagerDuty API documentation](https://v2.developer.pagerduty.com/v2/docs/send-an-event-events-api-v2#section-the-links-property).
+
+```yaml
+href: <tmpl_string>
+text: <tmpl_string>
+```
+
 ## `<pushover_config>`
 
 Pushover notifications are sent via the [Pushover API](https://pushover.net/api).