Expose database server_lifetime metric.

internal/collector/metrics.go

@@ -280,6 +280,22 @@ func buildMetrics(cfg config.Config) []metric {
 				return results
 			},
 		},
+		{
+			enabled: cfg.ExportDatabases,
+			name:    fqName(SubsystemDatabases, "server_lifetime"),
+			help:    "The maximum lifetime of a server connection for this database.",
+			labels:  []string{"name", "pool_mode"},
+			valType: prometheus.GaugeValue,
+			eval: func(res *storeResult) (results []metricResult) {
+				for _, database := range res.databases {
+					results = append(results, metricResult{
+						labels: []string{database.Name, database.PoolMode},
+						value:  float64(database.ServerLifetime),
+					})
+				}
+				return results
+			},
+		},
 		{
 			enabled: cfg.ExportLists,
 			name:    fqName(SubsystemLists, "items"),

internal/domain/domain.go

@@ -61,6 +61,7 @@ type Database struct {
 	CurrentConnections int64
 	Paused             int64
 	Disabled           int64
+	ServerLifetime     int64
 }
 
 // List represents list row.

internal/sqlstore/sql.go

@@ -72,7 +72,7 @@ func (s *Store) GetStats(ctx context.Context) ([]domain.Stat, error) {
 	var stats []domain.Stat
 
 	for rows.Next() {
-		dest := make([]interface{}, 0, len(columns))
+		dest := make([]any, 0, len(columns))
 
 		for _, column := range columns {
 			switch column {
@@ -145,7 +145,7 @@ func (s *Store) GetPools(ctx context.Context) ([]domain.Pool, error) {
 	var pools []pool
 
 	for rows.Next() {
-		dest := make([]interface{}, 0, len(columns))
+		dest := make([]any, 0, len(columns))
 
 		for _, column := range columns {
 			switch column {
@@ -237,7 +237,7 @@ func (s *Store) GetDatabases(ctx context.Context) ([]domain.Database, error) {
 	var databases []database
 
 	for rows.Next() {
-		dest := make([]interface{}, 0, len(columns))
+		dest := make([]any, 0, len(columns))
 
 		for _, column := range columns {
 			switch column {
@@ -300,6 +300,7 @@ func (s *Store) GetDatabases(ctx context.Context) ([]domain.Database, error) {
 			CurrentConnections: row.CurrentConnections,
 			Paused:             row.Paused,
 			Disabled:           row.Disabled,
+			ServerLifetime:     row.ServerLifetime,
 		})
 	}
 
@@ -323,7 +324,7 @@ func (s *Store) GetLists(ctx context.Context) ([]domain.List, error) {
 	var lists []domain.List
 
 	for rows.Next() {
-		dest := make([]interface{}, 0, len(columns))
+		dest := make([]any, 0, len(columns))
 
 		for _, column := range columns {
 			switch column {

internal/sqlstore/sql_test.go

@@ -18,22 +18,24 @@ func TestGetStats(t *testing.T) {
 
 	st := New(db)
 
-	data := map[string]interface{}{
-		"database":          "pgbouncer",
-		"total_xact_count":  1,
-		"total_query_count": 2,
-		"total_received":    3,
-		"total_sent":        4,
-		"total_xact_time":   5,
-		"total_query_time":  6,
-		"total_wait_time":   7,
-		"avg_xact_count":    8,
-		"avg_query_count":   9,
-		"avg_recv":          10,
-		"avg_sent":          11,
-		"avg_xact_time":     12,
-		"avg_query_time":    13,
-		"avg_wait_time":     14,
+	data := map[string]any{
+		"database":                      "pgbouncer",
+		"total_xact_count":              1,
+		"total_query_count":             2,
+		"total_received":                3,
+		"total_sent":                    4,
+		"total_xact_time":               5,
+		"total_query_time":              6,
+		"total_wait_time":               7,
+		"total_server_assignment_count": 8,
+		"avg_xact_count":                9,
+		"avg_query_count":               10,
+		"avg_recv":                      11,
+		"avg_sent":                      12,
+		"avg_xact_time":                 13,
+		"avg_query_time":                14,
+		"avg_wait_time":                 15,
+		"avg_server_assignment_count":   16,
 	}
 
 	mock.ExpectQuery("SHOW STATS").WillReturnRows(mapToRows(data))
@@ -51,13 +53,15 @@ func TestGetStats(t *testing.T) {
 	require.Equal(t, int64(data["total_xact_time"].(int)), stat.TotalXactTime)
 	require.Equal(t, int64(data["total_query_time"].(int)), stat.TotalQueryTime)
 	require.Equal(t, int64(data["total_wait_time"].(int)), stat.TotalWaitTime)
+	require.Equal(t, int64(data["total_server_assignment_count"].(int)), stat.TotalServerAssignmentCount)
 	require.Equal(t, int64(data["avg_xact_count"].(int)), stat.AverageXactCount)
 	require.Equal(t, int64(data["avg_query_count"].(int)), stat.AverageQueryCount)
 	require.Equal(t, int64(data["avg_recv"].(int)), stat.AverageReceived)
 	require.Equal(t, int64(data["avg_sent"].(int)), stat.AverageSent)
 	require.Equal(t, int64(data["avg_xact_time"].(int)), stat.AverageXactTime)
 	require.Equal(t, int64(data["avg_query_time"].(int)), stat.AverageQueryTime)
 	require.Equal(t, int64(data["avg_wait_time"].(int)), stat.AverageWaitTime)
+	require.Equal(t, int64(data["avg_server_assignment_count"].(int)), stat.AverageServerAssignmentCount)
 }
 
 func TestGetPools(t *testing.T) {
@@ -69,7 +73,7 @@ func TestGetPools(t *testing.T) {
 
 	st := New(db)
 
-	data := map[string]interface{}{
+	data := map[string]any{
 		"database":   "pgbouncer",
 		"user":       "myuser",
 		"cl_active":  1,
@@ -114,7 +118,7 @@ func TestGetDatabases(t *testing.T) {
 
 	st := New(db)
 
-	data := map[string]interface{}{
+	data := map[string]any{
 		"database":            "pgbouncer",
 		"name":                "myname",
 		"host":                "localhost",
@@ -127,6 +131,7 @@ func TestGetDatabases(t *testing.T) {
 		"current_connections": 8,
 		"paused":              9,
 		"disabled":            10,
+		"server_lifetime":     11,
 	}
 
 	mock.ExpectQuery("SHOW DATABASES").WillReturnRows(mapToRows(data))
@@ -148,6 +153,7 @@ func TestGetDatabases(t *testing.T) {
 	require.Equal(t, int64(data["current_connections"].(int)), database.CurrentConnections)
 	require.Equal(t, int64(data["paused"].(int)), database.Paused)
 	require.Equal(t, int64(data["disabled"].(int)), database.Disabled)
+	require.Equal(t, int64(data["server_lifetime"].(int)), database.ServerLifetime)
 }
 
 func TestGetLists(t *testing.T) {
@@ -159,7 +165,7 @@ func TestGetLists(t *testing.T) {
 
 	st := New(db)
 
-	data := map[string]interface{}{
+	data := map[string]any{
 		"list":  "mylist",
 		"items": 6,
 	}
@@ -175,7 +181,7 @@ func TestGetLists(t *testing.T) {
 	require.Equal(t, int64(data["items"].(int)), list.Items)
 }
 
-func mapToRows(data map[string]interface{}) *sqlmock.Rows {
+func mapToRows(data map[string]any) *sqlmock.Rows {
 	columns := make([]string, 0, len(data))
 	values := make([]driver.Value, 0, len(data))
 	for k, v := range data {