Add PagerDuty source field (PD-CEF) (#3106)

* Add new source field to PD config
* Update documentation

Signed-off-by: Oktarian Tilney-Bassett <oktariantilneybassett@improbable.io>

config/notifiers.go

@@ -217,6 +217,7 @@ type PagerdutyConfig struct {
 	Details     map[string]string `yaml:"details,omitempty" json:"details,omitempty"`
 	Images      []PagerdutyImage  `yaml:"images,omitempty" json:"images,omitempty"`
 	Links       []PagerdutyLink   `yaml:"links,omitempty" json:"links,omitempty"`
+	Source      string            `yaml:"source,omitempty" json:"source,omitempty"`
 	Severity    string            `yaml:"severity,omitempty" json:"severity,omitempty"`
 	Class       string            `yaml:"class,omitempty" json:"class,omitempty"`
 	Component   string            `yaml:"component,omitempty" json:"component,omitempty"`
@@ -249,6 +250,9 @@ func (c *PagerdutyConfig) UnmarshalYAML(unmarshal func(interface{}) error) error
 	if c.Details == nil {
 		c.Details = make(map[string]string)
 	}
+	if c.Source == "" {
+		c.Source = c.Client
+	}
 	for k, v := range DefaultPagerdutyDetails {
 		if _, ok := c.Details[k]; !ok {
 			c.Details[k] = v

config/notifiers_test.go

@@ -17,6 +17,8 @@ import (
 	"strings"
 	"testing"
 
+	"github.com/stretchr/testify/require"
+
 	"gopkg.in/yaml.v2"
 )
 
@@ -146,6 +148,40 @@ details:
 	}
 }
 
+func TestPagerDutySource(t *testing.T) {
+	for _, tc := range []struct {
+		title string
+		in    string
+
+		expectedSource string
+	}{
+		{
+			title: "check source field is backward compatible",
+			in: `
+routing_key: 'xyz'
+client: 'alert-manager-client'
+`,
+			expectedSource: "alert-manager-client",
+		},
+		{
+			title: "check source field is set",
+			in: `
+routing_key: 'xyz'
+client: 'alert-manager-client'
+source: 'alert-manager-source'
+`,
+			expectedSource: "alert-manager-source",
+		},
+	} {
+		t.Run(tc.title, func(t *testing.T) {
+			var cfg PagerdutyConfig
+			err := yaml.UnmarshalStrict([]byte(tc.in), &cfg)
+			require.NoError(t, err)
+			require.Equal(t, tc.expectedSource, cfg.Source)
+		})
+	}
+}
+
 func TestWebhookURLIsPresent(t *testing.T) {
 	in := `{}`
 	var cfg WebhookConfig

docs/configuration.md

@@ -660,6 +660,9 @@ service_key: <tmpl_secret>
 # Severity of the incident.
 [ severity: <tmpl_string> | default = 'error' ]
 
+# Unique location of the affected system.
+[ source: <tmpl_string> | default = client ]
+
 # A set of arbitrary key/value pairs that provide further detail
 # about the incident.
 [ details: { <string>: <tmpl_string>, ... } | default = {

notify/pagerduty/pagerduty.go

@@ -219,7 +219,7 @@ func (n *Notifier) notifyV2(
 		Links:       make([]pagerDutyLink, 0, len(n.conf.Links)),
 		Payload: &pagerDutyPayload{
 			Summary:       summary,
-			Source:        tmpl(n.conf.Client),
+			Source:        tmpl(n.conf.Source),
 			Severity:      tmpl(n.conf.Severity),
 			CustomDetails: details,
 			Class:         tmpl(n.conf.Class),