Add phone call support

Implements: https://todo.xenrox.net/~xenrox/ntfy-alertmanager/18

README.md

@@ -17,7 +17,7 @@ the configuration file will be read from `/etc/ntfy-alertmanager/config`. The fo
 of this file is [scfg].
 
 ntfy-alertmanager has support for setting ntfy [priority], [tags], [icon], [action buttons]
-(which can be used to create an Alertmanager silence) and [email notifications].
+(which can be used to create an Alertmanager silence), [email notifications] and [phone calls].
 Define a decreasing order of labels in the config file and map those labels to tags, priority, an icon or an email address.
 
 -   For priority and icon the first found value will be chosen. An icon for "resolved" alerts will take precedence.
@@ -49,6 +49,8 @@ labels {
         icon "https://foo.com/critical.png"
         # Forward messages which severity "critical" to the specified email address.
         email-address foo@bar.com
+        # Call the specified number. Use `yes` to pick the first of your verified numbers.
+        call yes
     }
 
     severity "info" {
@@ -77,6 +79,8 @@ ntfy {
     access-token foobar
     # Forward all messages to the specified email address.
     email-address foo@bar.com
+    # Call the specified number for all alerts. Use `yes` to pick the first of your verified numbers.
+    call +123456789
 }
 
 alertmanager {
@@ -140,6 +144,7 @@ or write to me directly on matrix [@xenrox:xenrox.net].
 [icon]: https://docs.ntfy.sh/publish/#icons
 [action buttons]: https://docs.ntfy.sh/publish/#action-buttons
 [email notifications]: https://docs.ntfy.sh/publish/#e-mail-notifications
+[phone calls]: https://ntfy.xenrox.net/docs/publish/#phone-calls
 [issue tracker]: https://todo.xenrox.net/~xenrox/ntfy-alertmanager
 [mailing list]: https://lists.xenrox.net/~xenrox/public-inbox
 [@xenrox:xenrox.net]: https://matrix.to/#/@xenrox:xenrox.net

config.go

@@ -43,6 +43,7 @@ type ntfyConfig struct {
 	Password     string
 	AccessToken  string
 	emailAddress string
+	call         string
 }
 
 type labels struct {
@@ -55,6 +56,7 @@ type labelConfig struct {
 	Tags         []string
 	Icon         string
 	emailAddress string
+	call         string
 }
 
 type cacheConfig struct {
@@ -210,6 +212,13 @@ func readConfig(path string) (*config, error) {
 					}
 				}
 
+				d = labelDir.Children.Get("call")
+				if d != nil {
+					if err := d.ParseParams(&labelConfig.call); err != nil {
+						return nil, err
+					}
+				}
+
 				labels[fmt.Sprintf("%s:%s", labelName, name)] = *labelConfig
 			}
 		}
@@ -267,6 +276,13 @@ func readConfig(path string) (*config, error) {
 		}
 	}
 
+	d = ntfyDir.Children.Get("call")
+	if d != nil {
+		if err := d.ParseParams(&config.ntfy.call); err != nil {
+			return nil, err
+		}
+	}
+
 	cacheDir := cfg.Get("cache")
 
 	if cacheDir != nil {

config_test.go

@@ -25,6 +25,7 @@ labels {
         tags "rotating_light"
         icon "https://foo.com/critical.png"
         email-address foo@bar.com
+        call yes
     }
 
     severity "info" {
@@ -76,6 +77,7 @@ cache {
 					Tags:         []string{"rotating_light"},
 					Icon:         "https://foo.com/critical.png",
 					emailAddress: "foo@bar.com",
+					call:         "yes",
 				},
 				"severity:info":        {Priority: "1"},
 				"instance:example.com": {Tags: []string{"computer", "example"}},

main.go

@@ -52,6 +52,7 @@ type notification struct {
 	tags         string
 	icon         string
 	emailAddress string
+	call         string
 	silenceBody  string
 	fingerprint  string
 	status       string
@@ -102,6 +103,7 @@ func (br *bridge) singleAlertNotifications(p *payload) []*notification {
 		}
 
 		n.emailAddress = br.cfg.ntfy.emailAddress
+		n.call = br.cfg.ntfy.call
 
 		for _, labelName := range br.cfg.labels.Order {
 			val, ok := alert.Labels[labelName]
@@ -126,6 +128,10 @@ func (br *bridge) singleAlertNotifications(p *payload) []*notification {
 				n.emailAddress = labelConfig.emailAddress
 			}
 
+			if n.call == "" {
+				n.call = labelConfig.call
+			}
+
 			for _, val := range labelConfig.Tags {
 				if !sliceContains(tags, val) {
 					tags = append(tags, val)
@@ -205,6 +211,7 @@ func (br *bridge) multiAlertNotification(p *payload) *notification {
 	}
 
 	n.emailAddress = br.cfg.ntfy.emailAddress
+	n.call = br.cfg.ntfy.call
 
 	for _, labelName := range br.cfg.labels.Order {
 		val, ok := p.CommonLabels[labelName]
@@ -229,6 +236,10 @@ func (br *bridge) multiAlertNotification(p *payload) *notification {
 			n.emailAddress = labelConfig.emailAddress
 		}
 
+		if n.call == "" {
+			n.call = labelConfig.call
+		}
+
 		for _, val := range labelConfig.Tags {
 			if !sliceContains(tags, val) {
 				tags = append(tags, val)
@@ -287,6 +298,10 @@ func (br *bridge) publish(n *notification) error {
 		req.Header.Set("X-Email", n.emailAddress)
 	}
 
+	if n.call != "" {
+		req.Header.Set("X-Call", n.call)
+	}
+
 	if n.silenceBody != "" {
 		url := br.cfg.BaseURL + "/silences"