Fix handling of the global smtp_require_tls field in Alertmanager con…

…figuration (prometheus-operator#3960)

* Added test for smtp_require_tls global flag

* pkg/alertmanager: omit smtp_require_tls when unspecified

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

* pkg/alertmanager: omit global resolve_timeout if empty

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

Co-authored-by: Martin Dostal <dostal@utu.unassigned-domain>

pkg/alertmanager/amcfg_test.go

@@ -18,10 +18,12 @@ import (
 	"context"
 	"net/url"
 	"testing"
+	"time"
 
 	"github.com/google/go-cmp/cmp"
 	"github.com/prometheus-operator/prometheus-operator/pkg/assets"
 	"github.com/prometheus/alertmanager/config"
+	"github.com/prometheus/common/model"
 	corev1 "k8s.io/api/core/v1"
 	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
 	"k8s.io/client-go/kubernetes"
@@ -58,6 +60,66 @@ func TestGenerateConfig(t *testing.T) {
 receivers:
 - name: "null"
 templates: []
+`,
+		},
+		{
+			name:    "skeleton base with global send_revolved, no CRs",
+			kclient: fake.NewSimpleClientset(),
+			baseConfig: alertmanagerConfig{
+				Global: &globalConfig{
+					ResolveTimeout: func(d model.Duration) *model.Duration { return &d }(model.Duration(time.Minute)),
+				},
+				Route:     &route{Receiver: "null"},
+				Receivers: []*receiver{{Name: "null"}},
+			},
+			amConfigs: map[string]*monitoringv1alpha1.AlertmanagerConfig{},
+			expected: `global:
+  resolve_timeout: 1m
+route:
+  receiver: "null"
+receivers:
+- name: "null"
+templates: []
+`,
+		},
+		{
+			name:    "skeleton base with global smtp_require_tls set to false, no CRs",
+			kclient: fake.NewSimpleClientset(),
+			baseConfig: alertmanagerConfig{
+				Global: &globalConfig{
+					SMTPRequireTLS: func(b bool) *bool { return &b }(false),
+				},
+				Route:     &route{Receiver: "null"},
+				Receivers: []*receiver{{Name: "null"}},
+			},
+			amConfigs: map[string]*monitoringv1alpha1.AlertmanagerConfig{},
+			expected: `global:
+  smtp_require_tls: false
+route:
+  receiver: "null"
+receivers:
+- name: "null"
+templates: []
+`,
+		},
+		{
+			name:    "skeleton base with global smtp_require_tls set to true, no CRs",
+			kclient: fake.NewSimpleClientset(),
+			baseConfig: alertmanagerConfig{
+				Global: &globalConfig{
+					SMTPRequireTLS: func(b bool) *bool { return &b }(true),
+				},
+				Route:     &route{Receiver: "null"},
+				Receivers: []*receiver{{Name: "null"}},
+			},
+			amConfigs: map[string]*monitoringv1alpha1.AlertmanagerConfig{},
+			expected: `global:
+  smtp_require_tls: true
+route:
+  receiver: "null"
+receivers:
+- name: "null"
+templates: []
 `,
 		},
 		{
@@ -542,7 +604,6 @@ templates: []
 				},
 			},
 			expected: `global:
-  resolve_timeout: 0s
   slack_api_url: http://slack.example.com
 route:
   receiver: "null"

pkg/alertmanager/types.go

@@ -39,7 +39,7 @@ type alertmanagerConfig struct {
 type globalConfig struct {
 	// ResolveTimeout is the time after which an alert is declared resolved
 	// if it has not been updated.
-	ResolveTimeout model.Duration `yaml:"resolve_timeout" json:"resolve_timeout"`
+	ResolveTimeout *model.Duration `yaml:"resolve_timeout,omitempty" json:"resolve_timeout,omitempty"`
 
 	HTTPConfig *commoncfg.HTTPClientConfig `yaml:"http_config,omitempty" json:"http_config,omitempty"`
 
@@ -50,7 +50,7 @@ type globalConfig struct {
 	SMTPAuthPassword string          `yaml:"smtp_auth_password,omitempty" json:"smtp_auth_password,omitempty"`
 	SMTPAuthSecret   string          `yaml:"smtp_auth_secret,omitempty" json:"smtp_auth_secret,omitempty"`
 	SMTPAuthIdentity string          `yaml:"smtp_auth_identity,omitempty" json:"smtp_auth_identity,omitempty"`
-	SMTPRequireTLS   bool            `yaml:"smtp_require_tls,omitempty" json:"smtp_require_tls,omitempty"`
+	SMTPRequireTLS   *bool           `yaml:"smtp_require_tls,omitempty" json:"smtp_require_tls,omitempty"`
 	SlackAPIURL      *config.URL     `yaml:"slack_api_url,omitempty" json:"slack_api_url,omitempty"`
 	PagerdutyURL     *config.URL     `yaml:"pagerduty_url,omitempty" json:"pagerduty_url,omitempty"`
 	HipchatAPIURL    *config.URL     `yaml:"hipchat_api_url,omitempty" json:"hipchat_api_url,omitempty"`