feat(controllers): add support for instanceMatchSelector

controllers/controller_shared.go

@@ -4,6 +4,7 @@ import (
 	"bytes"
 	"context"
 	"encoding/json"
+	"slices"
 	"time"
 
 	"github.com/grafana/grafana-operator/v5/api/v1beta1"
@@ -33,9 +34,53 @@ func GetMatchingInstances(ctx context.Context, k8sClient client.Client, labelSel
 	opts := []client.ListOption{
 		client.MatchingLabels(labelSelector.MatchLabels),
 	}
-
 	err := k8sClient.List(ctx, &list, opts...)
-	return list, err
+
+	var selectedList v1beta1.GrafanaList
+
+	for _, instance := range list.Items {
+		selected := labelsSatisfyMatchExpressions(instance.Labels, labelSelector.MatchExpressions)
+		if selected {
+			selectedList.Items = append(selectedList.Items, instance)
+		}
+	}
+
+	return selectedList, err
+}
+
+func labelsSatisfyMatchExpressions(labels map[string]string, matchExpressions []metav1.LabelSelectorRequirement) bool {
+	// To preserve support for scenario with instanceSelector: {}
+	if len(labels) == 0 {
+		return true
+	}
+
+	if len(matchExpressions) == 0 {
+		return true
+	}
+
+	for _, matchExpression := range matchExpressions {
+		selected := false
+
+		if label, ok := labels[matchExpression.Key]; ok {
+			switch matchExpression.Operator {
+			case metav1.LabelSelectorOpDoesNotExist:
+				selected = false
+			case metav1.LabelSelectorOpExists:
+				selected = true
+			case metav1.LabelSelectorOpIn:
+				selected = slices.Contains(matchExpression.Values, label)
+			case metav1.LabelSelectorOpNotIn:
+				selected = !slices.Contains(matchExpression.Values, label)
+			}
+		}
+
+		// All matchExpressions must evaluate to true in order to satisfy the conditions
+		if !selected {
+			return false
+		}
+	}
+
+	return true
 }
 
 func ReconcilePlugins(ctx context.Context, k8sClient client.Client, scheme *runtime.Scheme, grafana *v1beta1.Grafana, plugins v1beta1.PluginList, resource string) error {

controllers/controller_shared_test.go

@@ -0,0 +1,228 @@
+/*
+Copyright 2022.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package controllers
+
+import (
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
+)
+
+func TestLabelsSatisfyMatchExpressions(t *testing.T) {
+	tests := []struct {
+		name             string
+		labels           map[string]string
+		matchExpressions []metav1.LabelSelectorRequirement
+		want             bool
+	}{
+		{
+			name:             "No labels and no expressions",
+			labels:           map[string]string{},
+			matchExpressions: []metav1.LabelSelectorRequirement{},
+			want:             true,
+		},
+		{
+			name:   "No labels",
+			labels: map[string]string{},
+			matchExpressions: []metav1.LabelSelectorRequirement{
+				{
+					Operator: metav1.LabelSelectorOpExists,
+					Key:      "dashboards",
+				},
+			},
+			want: true,
+		},
+		{
+			name: "No matchExpressions",
+			labels: map[string]string{
+				"dashboards": "grafana",
+			},
+			matchExpressions: []metav1.LabelSelectorRequirement{},
+			want:             true,
+		},
+		{
+			name: "Matches DoesNotExist",
+			labels: map[string]string{
+				"dashboards": "grafana",
+			},
+			matchExpressions: []metav1.LabelSelectorRequirement{
+				{
+					Operator: metav1.LabelSelectorOpDoesNotExist,
+					Key:      "dashboards",
+				},
+			},
+			want: false,
+		},
+		{
+			name: "Matches Exists",
+			labels: map[string]string{
+				"dashboards": "grafana",
+			},
+			matchExpressions: []metav1.LabelSelectorRequirement{
+				{
+					Operator: metav1.LabelSelectorOpExists,
+					Key:      "dashboards",
+				},
+			},
+			want: true,
+		},
+		{
+			name: "Matches In",
+			labels: map[string]string{
+				"dashboards": "grafana",
+			},
+			matchExpressions: []metav1.LabelSelectorRequirement{
+				{
+					Operator: metav1.LabelSelectorOpIn,
+					Key:      "dashboards",
+					Values: []string{
+						"grafana",
+					},
+				},
+			},
+			want: true,
+		},
+		{
+			name: "Matches NotIn",
+			labels: map[string]string{
+				"dashboards": "grafana",
+			},
+			matchExpressions: []metav1.LabelSelectorRequirement{
+				{
+					Operator: metav1.LabelSelectorOpNotIn,
+					Key:      "dashboards",
+					Values: []string{
+						"grafana",
+					},
+				},
+			},
+			want: false,
+		},
+		{
+			name: "Does not match In",
+			labels: map[string]string{
+				"dashboards": "grafana",
+			},
+			matchExpressions: []metav1.LabelSelectorRequirement{
+				{
+					Operator: metav1.LabelSelectorOpIn,
+					Key:      "dashboards",
+					Values: []string{
+						"grafana-external",
+					},
+				},
+			},
+			want: false,
+		},
+		{
+			name: "Does not match NotIn",
+			labels: map[string]string{
+				"dashboards": "grafana",
+			},
+			matchExpressions: []metav1.LabelSelectorRequirement{
+				{
+					Operator: metav1.LabelSelectorOpNotIn,
+					Key:      "dashboards",
+					Values: []string{
+						"grafana-external",
+					},
+				},
+			},
+			want: true,
+		},
+		{
+			name: "Matches multiple expressions",
+			labels: map[string]string{
+				"dashboards":  "grafana",
+				"environment": "production",
+			},
+			matchExpressions: []metav1.LabelSelectorRequirement{
+				{
+					Operator: metav1.LabelSelectorOpIn,
+					Key:      "dashboards",
+					Values: []string{
+						"grafana",
+					},
+				},
+				{
+					Operator: metav1.LabelSelectorOpIn,
+					Key:      "environment",
+					Values: []string{
+						"production",
+					},
+				},
+			},
+			want: true,
+		},
+		{
+			name: "Does not match one of expressions (matching labels, different value)",
+			labels: map[string]string{
+				"dashboards":  "grafana",
+				"environment": "production",
+			},
+			matchExpressions: []metav1.LabelSelectorRequirement{
+				{
+					Operator: metav1.LabelSelectorOpIn,
+					Key:      "dashboards",
+					Values: []string{
+						"grafana",
+					},
+				},
+				{
+					Operator: metav1.LabelSelectorOpIn,
+					Key:      "environment",
+					Values: []string{
+						"development",
+					},
+				},
+			},
+			want: false,
+		},
+		{
+			name: "Does not match any of expressions (different labels)",
+			labels: map[string]string{
+				"random-label-1": "random-value-1",
+				"random-label-2": "random-value-2",
+			},
+			matchExpressions: []metav1.LabelSelectorRequirement{
+				{
+					Operator: metav1.LabelSelectorOpIn,
+					Key:      "dashboards",
+					Values: []string{
+						"grafana",
+					},
+				},
+				{
+					Operator: metav1.LabelSelectorOpIn,
+					Key:      "environment",
+					Values: []string{
+						"development",
+					},
+				},
+			},
+			want: false,
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			got := labelsSatisfyMatchExpressions(tt.labels, tt.matchExpressions)
+			assert.Equal(t, tt.want, got)
+		})
+	}
+}