add tests

Author: maria-reynoso

pkg/metrics/kubernetes_test.go

@@ -0,0 +1,140 @@
+package metrics
+
+import (
+	"testing"
+
+	"github.com/sirupsen/logrus"
+	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
+
+	"github.com/prometheus/client_golang/prometheus"
+	dto "github.com/prometheus/client_model/go"
+	"sigs.k8s.io/controller-runtime/pkg/client/fake"
+)
+
+var fakeK8sClient = fake.NewFakeClient()
+
+func TestRegisterKubeVersion(t *testing.T) {
+	tests := []struct {
+		name           string
+		isLatest       bool
+		currentVersion string
+		latestVersion  string
+		channel        string
+		expectedValue  float64
+	}{
+		{
+			name:           "cluster is up to date",
+			isLatest:       true,
+			currentVersion: "1.28.2",
+			latestVersion:  "1.28.2",
+			channel:        "stable",
+			expectedValue:  1.0,
+		},
+		{
+			name:           "cluster needs update",
+			isLatest:       false,
+			currentVersion: "1.27.1",
+			latestVersion:  "1.28.2",
+			channel:        "stable",
+			expectedValue:  0.0,
+		},
+		{
+			name:           "cluster is ahead of stable",
+			isLatest:       true,
+			currentVersion: "1.29.0",
+			latestVersion:  "1.28.2",
+			channel:        "stable",
+			expectedValue:  1.0,
+		},
+		{
+			name:           "latest channel with pre-release",
+			isLatest:       false,
+			currentVersion: "1.28.1",
+			latestVersion:  "1.29.0-alpha.1",
+			channel:        "latest",
+			expectedValue:  0.0,
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			// Create a new metrics instance for each test to avoid interference
+			registry := prometheus.NewRegistry()
+			m := New(logrus.NewEntry(logrus.New()), registry, fakeK8sClient)
+
+			// Register the Kubernetes version
+			m.RegisterKubeVersion(tt.isLatest, tt.currentVersion, tt.latestVersion, tt.channel)
+
+			// Gather metrics
+			metricFamilies, err := registry.Gather()
+			require.NoError(t, err)
+
+			// Find the kubernetes version metric
+			var kubeMetric *dto.MetricFamily
+			for _, mf := range metricFamilies {
+				if mf.GetName() == "version_checker_is_latest_kube_version" {
+					kubeMetric = mf
+					break
+				}
+			}
+
+			require.NotNil(t, kubeMetric, "Kubernetes version metric should be present")
+			require.Len(t, kubeMetric.GetMetric(), 1, "Should have exactly one metric value")
+
+			metric := kubeMetric.GetMetric()[0]
+			assert.Equal(t, tt.expectedValue, metric.GetGauge().GetValue())
+
+			// Check labels
+			labels := metric.GetLabel()
+			assert.Len(t, labels, 3, "Should have 3 labels: current_version, latest_version, channel")
+
+			labelMap := make(map[string]string)
+			for _, label := range labels {
+				labelMap[label.GetName()] = label.GetValue()
+			}
+
+			assert.Equal(t, tt.currentVersion, labelMap["current_version"])
+			assert.Equal(t, tt.latestVersion, labelMap["latest_version"])
+			assert.Equal(t, tt.channel, labelMap["channel"])
+		})
+	}
+}
+
+func TestRegisterKubeVersion_MultipleChannels(t *testing.T) {
+	registry := prometheus.NewRegistry()
+	m := New(logrus.NewEntry(logrus.New()), registry, fakeK8sClient)
+
+	// Register metrics for different channels
+	m.RegisterKubeVersion(true, "1.28.2", "1.28.2", "stable")
+	m.RegisterKubeVersion(false, "1.28.2", "1.29.0-alpha.1", "latest")
+
+	// Gather metrics
+	metricFamilies, err := registry.Gather()
+	require.NoError(t, err)
+
+	// Find the kubernetes version metric
+	var kubeMetric *dto.MetricFamily
+	for _, mf := range metricFamilies {
+		if mf.GetName() == "version_checker_is_latest_kube_version" {
+			kubeMetric = mf
+			break
+		}
+	}
+
+	require.NotNil(t, kubeMetric, "Kubernetes version metric should be present")
+	require.Len(t, kubeMetric.GetMetric(), 2, "Should have exactly two metric values for different channels")
+
+	// Check that both metrics are present
+	channels := make(map[string]float64)
+	for _, metric := range kubeMetric.GetMetric() {
+		labelMap := make(map[string]string)
+		for _, label := range metric.GetLabel() {
+			labelMap[label.GetName()] = label.GetValue()
+		}
+		channels[labelMap["channel"]] = metric.GetGauge().GetValue()
+	}
+
+	assert.Equal(t, 1.0, channels["stable"], "Stable channel should be up to date")
+	assert.Equal(t, 0.0, channels["latest"], "Latest channel should need update")
+}