chore: add pool.Pooler interface to pgbouncer/metricsserver (cloudnat…

…ive-pg#2480) This patch leverages the pool.Pooler interface to add unit tests for pgbouncer metrics server. Partially Close cloudnative-pg#2358 Signed-off-by: Armando Ruocco <[email protected]> Signed-off-by: Jaime Silvela <[email protected]> Co-authored-by: Jaime Silvela <[email protected]>
josh-heyer · Aug 2, 2023 · 11e051c · 11e051c
1 parent 5402903
commit 11e051c
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Showing 5 changed files with 399 additions and 2 deletions.
diff --git a/pkg/management/pgbouncer/metricsserver/metricsserver_test.go b/pkg/management/pgbouncer/metricsserver/metricsserver_test.go
@@ -0,0 +1,50 @@
+/*
+Copyright The CloudNativePG Contributors
+
+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 metricsserver
+
+import (
+	. "github.com/onsi/ginkgo/v2"
+	. "github.com/onsi/gomega"
+)
+
+var _ = Describe("MetricsServer", func() {
+	Describe("Setup", func() {
+		BeforeEach(func() {
+			server = nil
+			registry = nil
+			exporter = nil
+		})
+
+		It("should register exporters and collectors successfully", func() {
+			err := Setup()
+			Expect(err).NotTo(HaveOccurred())
+
+			mfs, err := registry.Gather()
+			Expect(err).NotTo(HaveOccurred())
+			Expect(mfs).NotTo(BeEmpty())
+
+			Expect(exporter.Metrics.CollectionsTotal).NotTo(BeNil())
+			Expect(exporter.Metrics.PgCollectionErrors).NotTo(BeNil())
+			Expect(exporter.Metrics.Error).NotTo(BeNil())
+			Expect(exporter.Metrics.CollectionDuration).NotTo(BeNil())
+			Expect(exporter.Metrics.PgbouncerUp).NotTo(BeNil())
+			Expect(exporter.Metrics.ShowLists).NotTo(BeNil())
+			Expect(exporter.Metrics.ShowPools).NotTo(BeNil())
+			Expect(exporter.Metrics.ShowStats).NotTo(BeNil())
+		})
+	})
+})
diff --git a/pkg/management/pgbouncer/metricsserver/pgbouncer_collector.go b/pkg/management/pgbouncer/metricsserver/pgbouncer_collector.go
@@ -36,7 +36,7 @@ const PrometheusNamespace = "cnpg"
 // Exporter exports a set of metrics and collectors on a given postgres instance
 type Exporter struct {
 	Metrics *metrics
-	pool    *pool.ConnectionPool
+	pool    pool.Pooler
 }
 
 // metrics here are related to the exporter itself, which is instrumented to
@@ -145,7 +145,7 @@ func (e *Exporter) GetPgBouncerDB() (*sql.DB, error) {
 }
 
 // ConnectionPool gets or initializes the connection pool for this instance
-func (e *Exporter) ConnectionPool() *pool.ConnectionPool {
+func (e *Exporter) ConnectionPool() pool.Pooler {
 	if e.pool == nil {
 		dsn := fmt.Sprintf(
 			"host=%s port=%v user=%s sslmode=disable",

diff --git a/pkg/management/pgbouncer/metricsserver/pools_test.go b/pkg/management/pgbouncer/metricsserver/pools_test.go
@@ -0,0 +1,139 @@
+/*
+Copyright The CloudNativePG Contributors
+
+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 metricsserver
+
+import (
+	"database/sql"
+
+	"github.com/DATA-DOG/go-sqlmock"
+	"github.com/prometheus/client_golang/prometheus"
+
+	. "github.com/onsi/ginkgo/v2"
+	. "github.com/onsi/gomega"
+)
+
+var _ = Describe("Exporter", func() {
+	var (
+		registry  *prometheus.Registry
+		db        *sql.DB
+		mock      sqlmock.Sqlmock
+		exp       *Exporter
+		ch        chan prometheus.Metric
+		columns16 = []string{
+			"database",
+			"user",
+			"cl_active",
+			"cl_waiting",
+			"cl_active_cancel_req",
+			"cl_waiting_cancel_req",
+			"sv_active",
+			"sv_active_cancel",
+			"sv_being_canceled",
+			"sv_idle",
+			"sv_used",
+			"sv_tested",
+			"sv_login",
+			"maxwait",
+			"maxwait_us",
+			"pool_mode",
+		}
+	)
+
+	BeforeEach(func() {
+		var err error
+		db, mock, err = sqlmock.New()
+		Expect(err).ShouldNot(HaveOccurred())
+
+		exp = &Exporter{
+			Metrics: newMetrics(),
+			pool:    fakePooler{db: db},
+		}
+
+		registry = prometheus.NewRegistry()
+		registry.MustRegister(exp.Metrics.PgbouncerUp)
+		registry.MustRegister(exp.Metrics.Error)
+
+		ch = make(chan prometheus.Metric, 1000)
+	})
+
+	AfterEach(func() {
+		Expect(mock.ExpectationsWereMet()).To(Succeed())
+	})
+
+	Context("collectShowPools", func() {
+		It("should react properly if SQL shows no pools", func() {
+			mock.ExpectQuery("SHOW POOLS;").WillReturnError(sql.ErrNoRows)
+			exp.collectShowPools(ch, db)
+
+			metrics, err := registry.Gather()
+			Expect(err).ToNot(HaveOccurred())
+
+			pgBouncerUpValue := getMetric(metrics, pgBouncerUpKey).GetMetric()[0].GetGauge().GetValue()
+			Expect(pgBouncerUpValue).Should(BeEquivalentTo(0))
+
+			errorValue := getMetric(metrics, lastCollectionErrorKey).GetMetric()[0].GetGauge().GetValue()
+			Expect(errorValue).To(BeEquivalentTo(1))
+		})
+
+		It("should handle SQL rows scanning properly", func() {
+			mock.ExpectQuery("SHOW POOLS;").
+				WillReturnRows(sqlmock.NewRows(columns16).
+					AddRow("db1", "user1", 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, "session"))
+
+			exp.collectShowPools(ch, db)
+
+			metrics, err := registry.Gather()
+			Expect(err).ToNot(HaveOccurred())
+
+			pgBouncerUpValue := getMetric(metrics, pgBouncerUpKey).GetMetric()[0].GetGauge().GetValue()
+			Expect(pgBouncerUpValue).Should(BeEquivalentTo(1))
+
+			errorValue := getMetric(metrics, lastCollectionErrorKey).GetMetric()[0].GetGauge().GetValue()
+			Expect(errorValue).To(BeEquivalentTo(0))
+		})
+
+		It("should handle error during SQL rows scanning", func() {
+			mock.ExpectQuery("SHOW POOLS;").
+				WillReturnRows(sqlmock.NewRows(columns16).
+					AddRow("db1", "user1", "error", 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, "session"))
+
+			exp.collectShowPools(ch, db)
+
+			registry.MustRegister(exp.Metrics.PgCollectionErrors)
+
+			metrics, err := registry.Gather()
+			Expect(err).ToNot(HaveOccurred())
+
+			pgBouncerUpValue := getMetric(metrics, pgBouncerUpKey).GetMetric()[0].GetGauge().GetValue()
+			Expect(pgBouncerUpValue).Should(BeEquivalentTo(1))
+
+			errorsMetric := getMetric(metrics, collectionErrorsTotalKey).GetMetric()[0]
+			label := errorsMetric.GetLabel()[0]
+			Expect(*label.Name).To(BeEquivalentTo("collector"))
+			Expect(*label.Value).To(BeEquivalentTo("sql: Scan error on column index 2, name \"cl_active\": " +
+				"converting driver.Value type string (\"error\") to a int: invalid syntax"))
+			Expect(errorsMetric.GetCounter().GetValue()).To(BeEquivalentTo(1))
+		})
+
+		It("should return the correct integer value", func() {
+			Expect(poolModeToInt("session")).To(Equal(1))
+			Expect(poolModeToInt("transaction")).To(Equal(2))
+			Expect(poolModeToInt("statement")).To(Equal(3))
+			Expect(poolModeToInt("random")).To(Equal(-1))
+		})
+	})
+})
diff --git a/pkg/management/pgbouncer/metricsserver/stats_test.go b/pkg/management/pgbouncer/metricsserver/stats_test.go
@@ -0,0 +1,138 @@
+/*
+Copyright The CloudNativePG Contributors
+
+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 metricsserver
+
+import (
+	"database/sql"
+	"errors"
+
+	"github.com/DATA-DOG/go-sqlmock"
+	"github.com/prometheus/client_golang/prometheus"
+
+	. "github.com/onsi/ginkgo/v2"
+	. "github.com/onsi/gomega"
+)
+
+var _ = Describe("MetricsServer", func() {
+	const (
+		showStatsQuery = "SHOW STATS;"
+	)
+
+	var (
+		db       *sql.DB
+		mock     sqlmock.Sqlmock
+		exp      *Exporter
+		registry *prometheus.Registry
+		ch       chan prometheus.Metric
+	)
+
+	BeforeEach(func() {
+		var err error
+		db, mock, err = sqlmock.New()
+		Expect(err).NotTo(HaveOccurred())
+
+		exp = &Exporter{
+			Metrics: newMetrics(),
+			pool:    fakePooler{db: db},
+		}
+		registry = prometheus.NewRegistry()
+		registry.MustRegister(exp.Metrics.Error)
+		registry.MustRegister(exp.Metrics.ShowStats.TotalXactCount)
+		registry.MustRegister(exp.Metrics.ShowStats.TotalQueryCount)
+		registry.MustRegister(exp.Metrics.PgbouncerUp)
+
+		ch = make(chan prometheus.Metric, 1000)
+	})
+
+	Context("collectShowStats", func() {
+		It("should handle successful SQL query execution", func() {
+			mock.ExpectQuery(showStatsQuery).WillReturnRows(getShowStatsRows())
+
+			exp.collectShowStats(ch, db)
+
+			metrics, err := registry.Gather()
+			Expect(err).ToNot(HaveOccurred())
+
+			pgbouncerUpMetric := getMetric(metrics, "cnpg_pgbouncer_up")
+			Expect(pgbouncerUpMetric.GetMetric()[0].GetGauge().GetValue()).To(BeEquivalentTo(1))
+
+			lastCollectionErrorMetric := getMetric(metrics, "cnpg_pgbouncer_last_collection_error")
+			Expect(lastCollectionErrorMetric.GetMetric()[0].GetGauge().GetValue()).To(BeEquivalentTo(0))
+
+			totalXactCountMetric := getMetric(metrics, "cnpg_pgbouncer_stats_total_xact_count")
+			Expect(totalXactCountMetric.GetMetric()[0].GetGauge().GetValue()).To(BeEquivalentTo(1))
+
+			totalQueryCountMetric := getMetric(metrics, "cnpg_pgbouncer_stats_total_query_count")
+			Expect(totalQueryCountMetric.GetMetric()[0].GetGauge().GetValue()).To(BeEquivalentTo(2))
+		})
+
+		It("should handle error during SQL query execution", func() {
+			mock.ExpectQuery(showStatsQuery).WillReturnError(errors.New("database error"))
+
+			exp.collectShowStats(ch, db)
+
+			metrics, err := registry.Gather()
+			Expect(err).ToNot(HaveOccurred())
+
+			pgbouncerUpMetric := getMetric(metrics, "cnpg_pgbouncer_up")
+			Expect(pgbouncerUpMetric.GetMetric()[0].GetGauge().GetValue()).To(BeEquivalentTo(0))
+
+			lastCollectionErrorMetric := getMetric(metrics, "cnpg_pgbouncer_last_collection_error")
+			Expect(lastCollectionErrorMetric.GetMetric()[0].GetGauge().GetValue()).To(BeEquivalentTo(1))
+		})
+
+		It("should handle error during rows scanning", func() {
+			mock.ExpectQuery(showStatsQuery).
+				WillReturnRows(sqlmock.NewRows([]string{"total_xact_count"}).
+					AddRow("invalid"))
+
+			exp.collectShowStats(ch, db)
+
+			metrics, err := registry.Gather()
+			Expect(err).ToNot(HaveOccurred())
+
+			pgbouncerUpMetric := getMetric(metrics, "cnpg_pgbouncer_up")
+			Expect(pgbouncerUpMetric.GetMetric()[0].GetGauge().GetValue()).To(BeEquivalentTo(1))
+
+			lastCollectionErrorMetric := getMetric(metrics, "cnpg_pgbouncer_last_collection_error")
+			Expect(lastCollectionErrorMetric.GetMetric()[0].GetGauge().GetValue()).To(BeEquivalentTo(1))
+		})
+	})
+})
+
+func getShowStatsRows() *sqlmock.Rows {
+	columns := []string{
+		"database",
+		"total_xact_count",
+		"total_query_count",
+		"total_received",
+		"total_sent",
+		"total_xact_time",
+		"total_query_time",
+		"total_wait_time",
+		"avg_xact_count",
+		"avg_query_count",
+		"avg_recv",
+		"avg_sent",
+		"avg_xact_time",
+		"avg_query_time",
+		"avg_wait_time",
+	}
+
+	return sqlmock.NewRows(columns).
+		AddRow("db1", 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14)
+}