feat(api): add @cluster filter

internal/filters/autocomplete_test.go

@@ -38,8 +38,8 @@ var acTests = []acTest{
 				},
 				Receiver: "default",
 				Alertmanager: []models.AlertmanagerInstance{
-					{Name: "am1"},
-					{Name: "am2"},
+					{Cluster: "cluster", Name: "am1"},
+					{Cluster: "cluster", Name: "am2"},
 				},
 			},
 			{
@@ -50,9 +50,10 @@ var acTests = []acTest{
 				},
 				Receiver: "not default",
 				Alertmanager: []models.AlertmanagerInstance{
-					{Name: "am1"},
+					{Cluster: "cluster", Name: "am1"},
 					{
-						Name: "am2",
+						Cluster: "cluster",
+						Name:    "am2",
 						Silences: map[string]*models.Silence{
 							"1234567890": {
 								ID:        "1234567890",
@@ -73,6 +74,8 @@ var acTests = []acTest{
 			"@alertmanager!=am2",
 			"@alertmanager=am1",
 			"@alertmanager=am2",
+			"@cluster!=cluster",
+			"@cluster=cluster",
 			"@limit=10",
 			"@limit=50",
 			"@receiver!=default",

internal/filters/filter_cluster.go

@@ -0,0 +1,61 @@
+package filters
+
+import (
+	"fmt"
+	"strings"
+
+	"github.com/prymitive/karma/internal/models"
+)
+
+type alertmanagerClusterFilter struct {
+	alertFilter
+}
+
+func (filter *alertmanagerClusterFilter) Match(alert *models.Alert, matches int) bool {
+	if filter.IsValid {
+		var isMatch bool
+		for _, am := range alert.Alertmanager {
+			if filter.Matcher.Compare(am.Cluster, filter.Value) {
+				isMatch = true
+			}
+		}
+		if isMatch {
+			filter.Hits++
+		}
+		return isMatch
+	}
+	e := fmt.Sprintf("Match() called on invalid filter %#v", filter)
+	panic(e)
+}
+
+func newAlertmanagerClusterFilter() FilterT {
+	f := alertmanagerClusterFilter{}
+	return &f
+}
+
+func alertmanagerClusterAutocomplete(name string, operators []string, alerts []models.Alert) []models.Autocomplete {
+	tokens := map[string]models.Autocomplete{}
+	for _, alert := range alerts {
+		for _, am := range alert.Alertmanager {
+			for _, operator := range operators {
+				switch operator {
+				case equalOperator, notEqualOperator:
+					token := fmt.Sprintf("%s%s%s", name, operator, am.Cluster)
+					tokens[token] = makeAC(
+						token,
+						[]string{
+							name,
+							strings.TrimPrefix(name, "@"),
+							name + operator,
+						},
+					)
+				}
+			}
+		}
+	}
+	acData := make([]models.Autocomplete, 0, len(tokens))
+	for _, token := range tokens {
+		acData = append(acData, token)
+	}
+	return acData
+}

internal/filters/filter_test.go

@@ -587,6 +587,28 @@ var tests = []filterTest{
 		},
 		IsMatch: true,
 	},
+	{
+		Expression: "@cluster=foo",
+		IsValid:    true,
+		Alert:      models.Alert{},
+		IsMatch:    false,
+	},
+	{
+		Expression: "@cluster=HA",
+		IsValid:    true,
+		Alert: models.Alert{
+			Receiver: "by-name",
+		},
+		IsMatch: true,
+	},
+	{
+		Expression: "@cluster!=foo",
+		IsValid:    true,
+		Alert: models.Alert{
+			Receiver: "by-name",
+		},
+		IsMatch: true,
+	},
 	{
 		Expression: "@receiver=by-name",
 		IsValid:    true,
@@ -608,7 +630,7 @@ var tests = []filterTest{
 func TestFilters(t *testing.T) {
 	log.SetLevel(log.ErrorLevel)
 
-	am, err := alertmanager.NewAlertmanager("test", "http://localhost", alertmanager.WithRequestTimeout(time.Second))
+	am, err := alertmanager.NewAlertmanager("HA", "test", "http://localhost", alertmanager.WithRequestTimeout(time.Second))
 	if err != nil {
 		t.Error(err)
 	}
@@ -616,6 +638,7 @@ func TestFilters(t *testing.T) {
 		alert := models.Alert(ft.Alert)
 		alert.Alertmanager = []models.AlertmanagerInstance{
 			{
+				Cluster:    "HA",
 				Name:       am.Name,
 				Silences:   map[string]*models.Silence{},
 				SilencedBy: []string{},

internal/filters/registry.go

@@ -47,6 +47,13 @@ var AllFilters = []filterConfig{
 		Factory:            newAlertmanagerInstanceFilter,
 		Autocomplete:       alertmanagerInstanceAutocomplete,
 	},
+	{
+		Label:              "@cluster",
+		LabelRe:            regexp.MustCompile("^@cluster$"),
+		SupportedOperators: []string{regexpOperator, negativeRegexOperator, equalOperator, notEqualOperator},
+		Factory:            newAlertmanagerClusterFilter,
+		Autocomplete:       alertmanagerClusterAutocomplete,
+	},
 	{
 		Label:              "@state",
 		LabelRe:            regexp.MustCompile("^@state$"),