metrics tests

internal/metrics/metrics.go

@@ -39,9 +39,10 @@ func NewMetricsSubsystem(db *certdb.CertificateRequestsRepository) *PrometheusMe
 		log.Println(errors.Join(errors.New("error generating metrics repository: "), err))
 	}
 	metricsBackend := newPrometheusMetrics()
+	metricsBackend.generateMetrics(csrs)
 	go func() {
-		metricsBackend.generateMetrics(csrs)
 		time.Sleep(120 * ONE_SECOND)
+		metricsBackend.generateMetrics(csrs)
 	}()
 	metricsBackend.Handler = promhttp.HandlerFor(metricsBackend.registry, promhttp.HandlerOpts{})
 	return metricsBackend
@@ -97,10 +98,12 @@ func (pm *PrometheusMetrics) generateMetrics(csrs []certdb.CertificateRequest) {
 	for _, entry := range csrs {
 		if entry.Certificate == "" {
 			outstandingCSRCount += 1
+			continue
 		}
-		if entry.Certificate != "" && entry.Certificate != "rejected" {
-			certCount += 1
+		if entry.Certificate == "rejected" {
+			continue
 		}
+		certCount += 1
 		expiryDate := certificateExpiryDate(entry.Certificate)
 		daysRemaining := time.Until(expiryDate).Hours() / 24
 		if daysRemaining < 0 {

internal/metrics/metrics_test.go

@@ -1,11 +1,19 @@
 package metrics_test
 
 import (
+	"bytes"
+	"crypto/rand"
+	"crypto/rsa"
+	"crypto/x509"
+	"encoding/pem"
+	"fmt"
 	"log"
+	"math/big"
 	"net/http"
 	"net/http/httptest"
 	"strings"
 	"testing"
+	"time"
 
 	"github.com/canonical/gocert/internal/certdb"
 	metrics "github.com/canonical/gocert/internal/metrics"
@@ -41,3 +49,107 @@ func TestPrometheusHandler(t *testing.T) {
 		log.Fatalln(err)
 	}
 }
+
+// Generates a CSR and Certificate with the given days remaining
+func generateCertPair(daysRemaining int) (string, string) {
+	NotAfterTime := time.Now().AddDate(0, 0, daysRemaining)
+	key, _ := rsa.GenerateKey(rand.Reader, 2048)
+
+	csrTemplate := x509.CertificateRequest{}
+	certTemplate := x509.Certificate{
+		SerialNumber: big.NewInt(1),
+		NotAfter:     NotAfterTime,
+	}
+
+	csrBytes, _ := x509.CreateCertificateRequest(rand.Reader, &csrTemplate, key)
+	certBytes, _ := x509.CreateCertificate(rand.Reader, &certTemplate, &certTemplate, &key.PublicKey, key)
+
+	var buff bytes.Buffer
+	pem.Encode(&buff, &pem.Block{
+		Type:  "CERTIFICATE REQUEST",
+		Bytes: csrBytes,
+	})
+	csr := buff.String()
+	buff.Reset()
+	pem.Encode(&buff, &pem.Block{
+		Type:  "CERTIFICATE",
+		Bytes: certBytes,
+	})
+	cert := buff.String()
+	return csr, cert
+}
+
+func initializeTestDB(db *certdb.CertificateRequestsRepository) {
+	for i, v := range []int{5, 10, 32} {
+		csr, cert := generateCertPair(v)
+		_, err := db.Create(csr)
+		if err != nil {
+			log.Fatalf("couldn't create test csr:%s", err)
+		}
+		_, err = db.Update(fmt.Sprint(i+1), cert)
+		if err != nil {
+			log.Fatalf("couldn't create test cert:%s", err)
+		}
+	}
+}
+
+// TestMetrics tests some of the metrics that we currently collect.
+func TestMetrics(t *testing.T) {
+	db, err := certdb.NewCertificateRequestsRepository(":memory:", "CertificateReq")
+	if err != nil {
+		log.Fatalln(err)
+	}
+	initializeTestDB(db)
+	m := metrics.NewMetricsSubsystem(db)
+
+	request, _ := http.NewRequest("GET", "/", nil)
+	recorder := httptest.NewRecorder()
+	m.Handler.ServeHTTP(recorder, request)
+
+	if status := recorder.Code; status != http.StatusOK {
+		t.Errorf("handler returned wrong status code: got %v want %v", status, http.StatusOK)
+	}
+	if recorder.Body.String() == "" {
+		t.Errorf("handler returned an empty body")
+	}
+	for _, line := range strings.Split(recorder.Body.String(), "\n") {
+		if strings.Contains(line, "outstanding_certificate_requests ") && !strings.HasPrefix(line, "#") {
+			if !strings.HasSuffix(line, "0") {
+				t.Errorf("outstanding_certificate_requests expected to receive 0")
+			}
+		} else if strings.Contains(line, "certificate_requests ") && !strings.HasPrefix(line, "#") {
+			if !strings.HasSuffix(line, "3") {
+				t.Errorf("certificate_requests expected to receive 3")
+			}
+		} else if strings.Contains(line, "certificates ") && !strings.HasPrefix(line, "#") {
+			if !strings.HasSuffix(line, "3") {
+				t.Errorf("certificates expected to receive 3")
+			}
+		} else if strings.Contains(line, "certificates_expired ") && !strings.HasPrefix(line, "#") {
+			if !strings.HasSuffix(line, "0") {
+				t.Errorf("certificates_expired expected to receive 0")
+			}
+		} else if strings.Contains(line, "certificates_expiring_in_1_day ") && !strings.HasPrefix(line, "#") {
+			if !strings.HasSuffix(line, "0") {
+				t.Errorf("certificates_expiring_in_1_day expected to receive 0")
+			}
+		} else if strings.Contains(line, "certificates_expiring_in_7_days ") && !strings.HasPrefix(line, "#") {
+			if !strings.HasSuffix(line, "1") {
+				t.Errorf("certificates_expiring_in_7_days expected to receive 1")
+			}
+		} else if strings.Contains(line, "certificates_expiring_in_30_days ") && !strings.HasPrefix(line, "#") {
+			if !strings.HasSuffix(line, "2") {
+				t.Errorf("certificates_expiring_in_30_days expected to receive 2")
+			}
+		} else if strings.Contains(line, "certificates_expiring_in_90_days ") && !strings.HasPrefix(line, "#") {
+			if !strings.HasSuffix(line, "3") {
+				t.Errorf("certificates_expiring_in_90_days expected to receive 3")
+			}
+		}
+	}
+
+	err = db.Close()
+	if err != nil {
+		log.Fatalln(err)
+	}
+}