From 3b8ceda26a47d898f84773d608a7765ea6c37d66 Mon Sep 17 00:00:00 2001
From: Owen Diehl <ow.diehl@gmail.com>
Date: Wed, 24 Feb 2021 10:35:03 -0500
Subject: [PATCH] receiver unmarshaling tests

---
 go.mod                       |  1 +
 pkg/api/alertmanager.go      | 50 +++++++++++++++++++++++++++
 pkg/api/alertmanager_test.go | 65 ++++++++++++++++++++++++++++++++++++
 3 files changed, 116 insertions(+)
 create mode 100644 pkg/api/alertmanager_test.go

diff --git a/go.mod b/go.mod
index d8502021986..d4de040570e 100644
--- a/go.mod
+++ b/go.mod
@@ -10,6 +10,7 @@ require (
 	github.com/prometheus/alertmanager v0.21.1-0.20210211203738-a7ca7b1d2951
 	github.com/prometheus/client_golang v1.9.0
 	github.com/prometheus/common v0.15.0
+	github.com/stretchr/testify v1.7.0
 	golang.org/x/net v0.0.0-20210119194325-5f4716e94777 // indirect
 	golang.org/x/oauth2 v0.0.0-20210210192628-66670185b0cd // indirect
 	gopkg.in/check.v1 v1.0.0-20200227125254-8fa46927fb4f // indirect
diff --git a/pkg/api/alertmanager.go b/pkg/api/alertmanager.go
index c54c7f5f8f2..581c59614b7 100644
--- a/pkg/api/alertmanager.go
+++ b/pkg/api/alertmanager.go
@@ -1,6 +1,9 @@
 package api
 
 import (
+	"encoding/json"
+	"fmt"
+
 	"github.com/grafana/grafana/pkg/models"
 	amv2 "github.com/prometheus/alertmanager/api/v2/models"
 	"github.com/prometheus/alertmanager/config"
@@ -177,11 +180,58 @@ type ApiAlertingConfig struct {
 
 type GrafanaReceiver models.CreateAlertNotificationCommand
 
+type ReceiverType int
+
+const (
+	GrafanaManagedReceiver ReceiverType = iota
+	AMReceiver
+)
+
 type ApiReceiver struct {
 	config.Receiver
 	GrafanaReceivers
 }
 
+func (r *ApiReceiver) UnmarshalJSON(b []byte) error {
+	type plain ApiReceiver
+	if err := json.Unmarshal(b, (*plain)(r)); err != nil {
+		return err
+	}
+
+	hasGrafanaReceivers := len(r.GrafanaReceivers.GrafanaManagedReceivers) > 0
+
+	if hasGrafanaReceivers {
+		if len(r.EmailConfigs) > 0 {
+			return fmt.Errorf("cannot have both Alertmanager EmailConfigs & Grafana receivers together")
+		}
+		if len(r.PagerdutyConfigs) > 0 {
+			return fmt.Errorf("cannot have both Alertmanager PagerdutyConfigs & Grafana receivers together")
+		}
+		if len(r.SlackConfigs) > 0 {
+			return fmt.Errorf("cannot have both Alertmanager SlackConfigs & Grafana receivers together")
+		}
+		if len(r.WebhookConfigs) > 0 {
+			return fmt.Errorf("cannot have both Alertmanager WebhookConfigs & Grafana receivers together")
+		}
+		if len(r.OpsGenieConfigs) > 0 {
+			return fmt.Errorf("cannot have both Alertmanager OpsGenieConfigs & Grafana receivers together")
+		}
+		if len(r.WechatConfigs) > 0 {
+			return fmt.Errorf("cannot have both Alertmanager WechatConfigs & Grafana receivers together")
+		}
+		if len(r.PushoverConfigs) > 0 {
+			return fmt.Errorf("cannot have both Alertmanager PushoverConfigs & Grafana receivers together")
+		}
+		if len(r.VictorOpsConfigs) > 0 {
+			return fmt.Errorf("cannot have both Alertmanager VictorOpsConfigs & Grafana receivers together")
+		}
+
+	}
+
+	return nil
+
+}
+
 type GrafanaReceivers struct {
 	GrafanaManagedReceivers []*GrafanaReceiver `yaml:"grafana_managed_receiver_configs,omitempty" json:"grafana_managed_receiver_configs,omitempty"`
 }
diff --git a/pkg/api/alertmanager_test.go b/pkg/api/alertmanager_test.go
new file mode 100644
index 00000000000..1a47516d581
--- /dev/null
+++ b/pkg/api/alertmanager_test.go
@@ -0,0 +1,65 @@
+package api
+
+import (
+	"encoding/json"
+	"testing"
+
+	"github.com/prometheus/alertmanager/config"
+	"github.com/stretchr/testify/require"
+)
+
+func Test_ApiReceiver_Marshaling(t *testing.T) {
+	for _, tc := range []struct {
+		desc  string
+		input ApiReceiver
+		err   bool
+	}{
+		{
+			desc: "success AM",
+			input: ApiReceiver{
+				Receiver: config.Receiver{
+					Name:         "foo",
+					EmailConfigs: []*config.EmailConfig{{}},
+				},
+			},
+		},
+		{
+			desc: "success GM",
+			input: ApiReceiver{
+				Receiver: config.Receiver{
+					Name: "foo",
+				},
+				GrafanaReceivers: GrafanaReceivers{
+					GrafanaManagedReceivers: []*GrafanaReceiver{{}},
+				},
+			},
+		},
+		{
+			desc: "failure mixed",
+			input: ApiReceiver{
+				Receiver: config.Receiver{
+					Name:         "foo",
+					EmailConfigs: []*config.EmailConfig{{}},
+				},
+				GrafanaReceivers: GrafanaReceivers{
+					GrafanaManagedReceivers: []*GrafanaReceiver{{}},
+				},
+			},
+			err: true,
+		},
+	} {
+		t.Run(tc.desc, func(t *testing.T) {
+			encoded, err := json.Marshal(tc.input)
+			require.Nil(t, err)
+
+			var out ApiReceiver
+			err = json.Unmarshal(encoded, &out)
+
+			if tc.err {
+				require.Error(t, err)
+			} else {
+				require.Equal(t, tc.input, out)
+			}
+		})
+	}
+}