fix(alertmanager): disallow creating invalid channels (#9946)

pkg/alertmanager/signozalertmanager/provider.go

@@ -2,9 +2,10 @@ package signozalertmanager
 
 import (
 	"context"
+	"time"
+
 	"github.com/SigNoz/signoz/pkg/query-service/utils/labels"
 	"github.com/prometheus/common/model"
-	"time"
 
 	amConfig "github.com/prometheus/alertmanager/config"
 
@@ -191,7 +192,11 @@ func (provider *provider) CreateChannel(ctx context.Context, orgID string, recei
 		return err
 	}
 
-	channel := alertmanagertypes.NewChannelFromReceiver(receiver, orgID)
+	channel, err := alertmanagertypes.NewChannelFromReceiver(receiver, orgID)
+	if err != nil {
+		return err
+	}
+
 	return provider.configStore.CreateChannel(ctx, channel, alertmanagertypes.WithCb(func(ctx context.Context) error {
 		return provider.configStore.Set(ctx, config)
 	}))

pkg/types/alertmanagertypes/channel.go

@@ -16,6 +16,7 @@ import (
 var (
 	ErrCodeAlertmanagerChannelNotFound     = errors.MustNewCode("alertmanager_channel_not_found")
 	ErrCodeAlertmanagerChannelNameMismatch = errors.MustNewCode("alertmanager_channel_name_mismatch")
+	ErrCodeAlertmanagerChannelInvalid      = errors.MustNewCode("alertmanager_channel_invalid")
 )
 
 var (
@@ -41,9 +42,9 @@ type Channel struct {
 
 // NewChannelFromReceiver creates a new Channel from a Receiver.
 // It can return nil if the receiver is the default receiver.
-func NewChannelFromReceiver(receiver config.Receiver, orgID string) *Channel {
+func NewChannelFromReceiver(receiver config.Receiver, orgID string) (*Channel, error) {
 	if receiver.Name == DefaultReceiverName {
-		return nil
+		return nil, errors.Newf(errors.TypeInvalidInput, ErrCodeAlertmanagerChannelInvalid, "cannot use %s name as a channel name", receiver.Name)
 	}
 
 	// Initialize channel with common fields
@@ -98,7 +99,12 @@ func NewChannelFromReceiver(receiver config.Receiver, orgID string) *Channel {
 		break
 	}
 
-	return &channel
+	// If we were unable to find the channel type, return an error
+	if channel.Type == "" {
+		return nil, errors.Newf(errors.TypeInvalidInput, ErrCodeAlertmanagerChannelInvalid, "channel '%s' must have at least one notification configuration (e.g., email_configs, webhook_configs, slack_configs)", receiver.Name)
+	}
+
+	return &channel, nil
 }
 
 func NewConfigFromChannels(globalConfig GlobalConfig, routeConfig RouteConfig, channels Channels, orgID string) (*Config, error) {
@@ -163,9 +169,9 @@ func NewStatsFromChannels(channels Channels) map[string]any {
 }
 
 func (c *Channel) Update(receiver Receiver) error {
-	channel := NewChannelFromReceiver(receiver, c.OrgID)
-	if channel == nil {
-		return errors.Newf(errors.TypeInvalidInput, ErrCodeAlertmanagerChannelNotFound, "cannot find channel with id %s", c.ID.StringValue())
+	channel, err := NewChannelFromReceiver(receiver, c.OrgID)
+	if err != nil {
+		return err
 	}
 
 	if c.Name != channel.Name {

pkg/types/alertmanagertypes/channel_test.go

@@ -2,6 +2,7 @@ package alertmanagertypes
 
 import (
 	"encoding/json"
+	"net/url"
 	"testing"
 	"time"
 
@@ -228,3 +229,66 @@ func TestNewConfigFromChannels(t *testing.T) {
 		})
 	}
 }
+
+func TestNewChannelFromReceiver(t *testing.T) {
+	testCases := []struct {
+		name     string
+		receiver config.Receiver
+		expected *Channel
+		pass     bool
+	}{
+		{
+			name: "InvalidReceiver_OnlyName",
+			receiver: config.Receiver{
+				Name: "test-receiver",
+			},
+			expected: nil,
+			pass:     false,
+		},
+		{
+			name: "InvalidReceiver_DefaultReceiver",
+			receiver: config.Receiver{
+				Name: DefaultReceiverName,
+			},
+			expected: nil,
+			pass:     false,
+		},
+		{
+			name: "ValidReceiver_Slack",
+			receiver: config.Receiver{
+				Name: "test-receiver",
+				SlackConfigs: []*config.SlackConfig{
+					{
+						Channel: "#alerts",
+						APIURL:  &config.SecretURL{URL: &url.URL{Scheme: "https", Host: "slack.com", Path: "/api/test"}},
+						NotifierConfig: config.NotifierConfig{
+							VSendResolved: true,
+						},
+					},
+				},
+			},
+			expected: &Channel{
+				Name: "test-receiver",
+				Type: "slack",
+				Data: `{"name":"test-receiver","slack_configs":[{"send_resolved":true,"api_url":"https://slack.com/api/test","channel":"#alerts"}]}`,
+			},
+			pass: true,
+		},
+	}
+
+	for _, testCase := range testCases {
+		t.Run(testCase.name, func(t *testing.T) {
+			channel, err := NewChannelFromReceiver(testCase.receiver, "1")
+			if !testCase.pass {
+				assert.Error(t, err)
+				return
+			}
+
+			assert.NoError(t, err)
+			assert.Equal(t, testCase.expected.Name, channel.Name)
+			assert.Equal(t, testCase.expected.Type, channel.Type)
+			assert.Equal(t, testCase.expected.Data, channel.Data)
+		})
+	}
+
+}