Add APIVersion field to Prometheus.Spec.Alerting

Signed-off-by: Simon Pasquier <spasquie@redhat.com>

Documentation/api.md

@@ -98,6 +98,7 @@ AlertmanagerEndpoints defines a selection of a single Endpoints object containin
 | pathPrefix | Prefix for the HTTP path alerts are pushed to. | string | false |
 | tlsConfig | TLS Config to use for alertmanager connection. | *[TLSConfig](#tlsconfig) | false |
 | bearerTokenFile | BearerTokenFile to read from filesystem to use when authenticating to Alertmanager. | string | false |
+| apiVersion | Version of the Alertmanager API that Prometheus uses to send alerts. It can be \"v1\" or \"v2\". | string | false |
 
 [Back to TOC](#table-of-contents)
 

Documentation/compatibility.md

@@ -48,6 +48,7 @@ The versions of Prometheus compatible to be run with the Prometheus Operator are
 * v2.8.1
 * v2.9.2
 * v2.10.0
+* v2.11.0
 
 ## Alertmanager
 

example/prometheus-operator-crd/monitoring.coreos.com_prometheuses.yaml

@@ -699,6 +699,10 @@ spec:
                       Endpoints object containing alertmanager IPs to fire alerts
                       against.
                     properties:
+                      apiVersion:
+                        description: Version of the Alertmanager API that Prometheus
+                          uses to send alerts. It can be "v1" or "v2".
+                        type: string
                       bearerTokenFile:
                         description: BearerTokenFile to read from filesystem to use
                           when authenticating to Alertmanager.

pkg/apis/monitoring/v1/types.go

@@ -525,6 +525,9 @@ type AlertmanagerEndpoints struct {
 	// BearerTokenFile to read from filesystem to use when authenticating to
 	// Alertmanager.
 	BearerTokenFile string `json:"bearerTokenFile,omitempty"`
+	// Version of the Alertmanager API that Prometheus uses to send alerts. It
+	// can be "v1" or "v2".
+	APIVersion string `json:"apiVersion,omitempty"`
 }
 
 // ServiceMonitor defines monitoring for a set of services.

pkg/prometheus/promcfg.go

@@ -1029,6 +1029,12 @@ func (cg *configGenerator) generateAlertmanagerConfig(version semver.Version, am
 		cfg = append(cfg, yaml.MapItem{Key: "bearer_token_file", Value: am.BearerTokenFile})
 	}
 
+	if version.Major > 2 || (version.Major == 2 && version.Minor >= 11) {
+		if am.APIVersion == "v1" || am.APIVersion == "v2" {
+			cfg = append(cfg, yaml.MapItem{Key: "api_version", Value: am.APIVersion})
+		}
+	}
+
 	var relabelings []yaml.MapSlice
 
 	relabelings = append(relabelings, yaml.MapSlice{

pkg/prometheus/promcfg_test.go

@@ -477,6 +477,84 @@ alerting:
 	}
 }
 
+func TestAlertmanagerAPIVersion(t *testing.T) {
+	cg := &configGenerator{}
+	cfg, err := cg.generateConfig(
+		&monitoringv1.Prometheus{
+			ObjectMeta: metav1.ObjectMeta{
+				Name:      "test",
+				Namespace: "default",
+			},
+			Spec: monitoringv1.PrometheusSpec{
+				Version: "v2.11.0",
+				Alerting: &monitoringv1.AlertingSpec{
+					Alertmanagers: []monitoringv1.AlertmanagerEndpoints{
+						{
+							Name:       "alertmanager-main",
+							Namespace:  "default",
+							Port:       intstr.FromString("web"),
+							APIVersion: "v2",
+						},
+					},
+				},
+			},
+		},
+		nil,
+		nil,
+		map[string]BasicAuthCredentials{},
+		map[string]BearerToken{},
+		nil,
+		nil,
+		nil,
+		nil,
+	)
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	// If this becomes an endless sink of maintenance, then we should just
+	// change this to check that just the `api_version` is set with
+	// something like json-path.
+	expected := `global:
+  evaluation_interval: 30s
+  scrape_interval: 30s
+  external_labels:
+    prometheus: default/test
+    prometheus_replica: $(POD_NAME)
+rule_files: []
+scrape_configs: []
+alerting:
+  alert_relabel_configs:
+  - action: labeldrop
+    regex: prometheus_replica
+  alertmanagers:
+  - path_prefix: /
+    scheme: http
+    kubernetes_sd_configs:
+    - role: endpoints
+      namespaces:
+        names:
+        - default
+    api_version: v2
+    relabel_configs:
+    - action: keep
+      source_labels:
+      - __meta_kubernetes_service_name
+      regex: alertmanager-main
+    - action: keep
+      source_labels:
+      - __meta_kubernetes_endpoint_port_name
+      regex: web
+`
+
+	result := string(cfg)
+
+	if expected != result {
+		fmt.Println(pretty.Compare(expected, result))
+		t.Fatal("expected Prometheus configuration and actual configuration do not match")
+	}
+}
+
 func TestAdditionalAlertRelabelConfigs(t *testing.T) {
 	cg := &configGenerator{}
 	cfg, err := cg.generateConfig(

pkg/prometheus/statefulset.go

@@ -93,6 +93,7 @@ var (
 		"v2.8.1",
 		"v2.9.2",
 		"v2.10.0",
+		"v2.11.0",
 	}
 )