Add icon support

Implements: https://todo.xenrox.net/~xenrox/ntfy-alertmanager/12

README.md

@@ -16,10 +16,11 @@ You can specify the configuration file location with the `--config` flag. By def
 the configuration file will be read from `/etc/ntfy-alertmanager/config`. The format
 of this file is [scfg].
 
-ntfy-alertmanager has support for setting ntfy [priority] and [tags]. Define a
+ntfy-alertmanager has support for setting ntfy [priority], [tags], [icon] and [action buttons]
-decreasing order of labels in the config file and map those labels to tags or priority.
+(which can be used to create an Alertmanager silence).
+Define a decreasing order of labels in the config file and map those labels to tags, priority or an icon.
 
--   For priority the first found value will be chosen.
+-   For priority and icon the first found value will be chosen. An icon for "resolved" alerts will take precedence.
 -   Tags are added together.
 
 Example:
@@ -45,6 +46,7 @@ labels {
     severity "critical" {
         priority 5
         tags "rotating_light"
+        icon "https://foo.com/critical.png"
     }
 
     severity "info" {
@@ -56,9 +58,10 @@ labels {
     }
 }
 
-# Set tags for resolved alerts
+# Settings for resolved alerts
 resolved {
     tags "resolved,partying_face"
+    icon "https://foo.com/resolved.png"
 }
 
 ntfy {
@@ -118,6 +121,8 @@ Report bugs on the [issue tracker].
 [scfg]: https://git.sr.ht/~emersion/scfg
 [priority]: https://ntfy.sh/docs/publish/#message-priority
 [tags]: https://ntfy.sh/docs/publish/#tags-emojis
+[icon]: https://docs.ntfy.sh/publish/#icons
+[action buttons]: https://docs.ntfy.sh/publish/#action-buttons
 [issue tracker]: https://todo.xenrox.net/~xenrox/ntfy-alertmanager
 [docker image]: https://hub.docker.com/r/xenrox/ntfy-alertmanager
 [docker-compose file]: https://git.xenrox.net/~xenrox/ntfy-alertmanager/tree/master/item/docker/docker-compose.yml

config.go

@@ -43,6 +43,7 @@ type labels struct {
 type labelConfig struct {
 	Priority string
 	Tags     []string
+	Icon     string
 }
 
 type cacheConfig struct {
@@ -59,6 +60,7 @@ type alertmanagerConfig struct {
 
 type resolvedConfig struct {
 	Tags []string
+	Icon string
 }
 
 func readConfig(path string) (*config, error) {
@@ -169,6 +171,13 @@ func readConfig(path string) (*config, error) {
 					labelConfig.Tags = strings.Split(tags, ",")
 				}
 
+				d = labelDir.Children.Get("icon")
+				if d != nil {
+					if err := d.ParseParams(&labelConfig.Icon); err != nil {
+						return nil, err
+					}
+				}
+
 				labels[fmt.Sprintf("%s:%s", labelName, name)] = *labelConfig
 			}
 		}
@@ -288,6 +297,13 @@ func readConfig(path string) (*config, error) {
 
 			config.resolved.Tags = strings.Split(tags, ",")
 		}
+
+		d = resolvedDir.Children.Get("icon")
+		if d != nil {
+			if err := d.ParseParams(&config.resolved.Icon); err != nil {
+				return nil, err
+			}
+		}
 	}
 
 	return config, nil

config_test.go

@@ -30,6 +30,7 @@ labels {
     severity "critical" {
         priority 5
         tags "rotating_light"
+        icon "https://foo.com/critical.png"
     }
 
     severity "info" {
@@ -43,6 +44,7 @@ labels {
 
 resolved {
     tags "resolved,partying_face"
+    icon "https://foo.com/resolved.png"
 }
 
 ntfy {
@@ -85,7 +87,7 @@ cache {
 		ntfy:        ntfyConfig{Topic: "https://ntfy.sh/alertmanager-alerts", User: "user", Password: "pass"},
 		labels: labels{Order: []string{"severity", "instance"},
 			Label: map[string]labelConfig{
-				"severity:critical":    {Priority: "5", Tags: []string{"rotating_light"}},
+				"severity:critical":    {Priority: "5", Tags: []string{"rotating_light"}, Icon: "https://foo.com/critical.png"},
 				"severity:info":        {Priority: "1"},
 				"instance:example.com": {Tags: []string{"computer", "example"}},
 			},
@@ -99,6 +101,7 @@ cache {
 		},
 		resolved: resolvedConfig{
 			Tags: []string{"resolved", "partying_face"},
+			Icon: "https://foo.com/resolved.png",
 		},
 	}
 

main.go

@@ -49,6 +49,7 @@ type notification struct {
 	body        string
 	priority    string
 	tags        string
+	icon        string
 	silenceBody string
 	fingerprint fingerprint
 	status      string
@@ -90,6 +91,7 @@ func (rcv *receiver) singleAlertNotifications(p *payload) []*notification {
 		var tags []string
 		if alert.Status == "resolved" {
 			tags = append(tags, rcv.cfg.resolved.Tags...)
+			n.icon = rcv.cfg.resolved.Icon
 		}
 
 		for _, labelName := range rcv.cfg.labels.Order {
@@ -107,6 +109,10 @@ func (rcv *receiver) singleAlertNotifications(p *payload) []*notification {
 				n.priority = labelConfig.Priority
 			}
 
+			if n.icon == "" {
+				n.icon = labelConfig.Icon
+			}
+
 			for _, val := range labelConfig.Tags {
 				if !sliceContains(tags, val) {
 					tags = append(tags, val)
@@ -181,6 +187,7 @@ func (rcv *receiver) multiAlertNotification(p *payload) *notification {
 	var tags []string
 	if p.Status == "resolved" {
 		tags = append(tags, rcv.cfg.resolved.Tags...)
+		n.icon = rcv.cfg.resolved.Icon
 	}
 
 	for _, labelName := range rcv.cfg.labels.Order {
@@ -198,6 +205,10 @@ func (rcv *receiver) multiAlertNotification(p *payload) *notification {
 			priority = labelConfig.Priority
 		}
 
+		if n.icon == "" {
+			n.icon = labelConfig.Icon
+		}
+
 		for _, val := range labelConfig.Tags {
 			if !sliceContains(tags, val) {
 				tags = append(tags, val)
@@ -245,6 +256,10 @@ func (rcv *receiver) publish(n *notification) error {
 		req.Header.Set("X-Priority", n.priority)
 	}
 
+	if n.icon != "" {
+		req.Header.Set("X-Icon", n.icon)
+	}
+
 	if n.tags != "" {
 		req.Header.Set("X-Tags", n.tags)
 	}