Merge pull request '[GITEA] Add slow SQL query warning' (#1284) from Gusted/forgejo:slow-query into forgejo-dependency

Reviewed-on: https://codeberg.org/forgejo/forgejo/pulls/1284

models/db/engine.go

@@ -11,10 +11,13 @@ import (
 	"io"
 	"reflect"
 	"strings"
+	"time"
 
+	"code.gitea.io/gitea/modules/log"
 	"code.gitea.io/gitea/modules/setting"
 
 	"xorm.io/xorm"
+	"xorm.io/xorm/contexts"
 	"xorm.io/xorm/names"
 	"xorm.io/xorm/schemas"
 
@@ -147,6 +150,13 @@ func InitEngine(ctx context.Context) error {
 	xormEngine.SetConnMaxLifetime(setting.Database.ConnMaxLifetime)
 	xormEngine.SetDefaultContext(ctx)
 
+	if setting.Database.SlowQueryTreshold > 0 {
+		xormEngine.AddHook(&SlowQueryHook{
+			Treshold: setting.Database.SlowQueryTreshold,
+			Logger:   log.GetLogger("xorm"),
+		})
+	}
+
 	SetDefaultEngine(ctx, xormEngine)
 	return nil
 }
@@ -300,3 +310,21 @@ func SetLogSQL(ctx context.Context, on bool) {
 		sess.Engine().ShowSQL(on)
 	}
 }
+
+type SlowQueryHook struct {
+	Treshold time.Duration
+	Logger   log.Logger
+}
+
+var _ contexts.Hook = &SlowQueryHook{}
+
+func (SlowQueryHook) BeforeProcess(c *contexts.ContextHook) (context.Context, error) {
+	return c.Ctx, nil
+}
+
+func (h *SlowQueryHook) AfterProcess(c *contexts.ContextHook) error {
+	if c.ExecuteTime >= h.Treshold {
+		h.Logger.Log(8, log.WARN, "[Slow SQL Query] %s %v - %v", c.SQL, c.Args, c.ExecuteTime)
+	}
+	return nil
+}

models/db/engine_test.go

@@ -6,15 +6,19 @@ package db_test
 import (
 	"path/filepath"
 	"testing"
+	"time"
 
 	"code.gitea.io/gitea/models/db"
 	issues_model "code.gitea.io/gitea/models/issues"
 	"code.gitea.io/gitea/models/unittest"
+	"code.gitea.io/gitea/modules/log"
 	"code.gitea.io/gitea/modules/setting"
+	"code.gitea.io/gitea/modules/test"
 
 	_ "code.gitea.io/gitea/cmd" // for TestPrimaryKeys
 
 	"github.com/stretchr/testify/assert"
+	"xorm.io/xorm"
 )
 
 func TestDumpDatabase(t *testing.T) {
@@ -85,3 +89,37 @@ func TestPrimaryKeys(t *testing.T) {
 		}
 	}
 }
+
+func TestSlowQuery(t *testing.T) {
+	lc, cleanup := test.NewLogChecker("slow-query")
+	lc.StopMark("[Slow SQL Query]")
+	defer cleanup()
+
+	e := db.GetEngine(db.DefaultContext)
+	engine, ok := e.(*xorm.Engine)
+	assert.True(t, ok)
+
+	// It's not possible to clean this up with XORM, but it's luckily not harmful
+	// to leave around.
+	engine.AddHook(&db.SlowQueryHook{
+		Treshold: time.Second * 10,
+		Logger:   log.GetLogger("slow-query"),
+	})
+
+	// NOOP query.
+	e.Exec("SELECT 1 WHERE false;")
+
+	_, stopped := lc.Check(100 * time.Millisecond)
+	assert.False(t, stopped)
+
+	engine.AddHook(&db.SlowQueryHook{
+		Treshold: 0, // Every query should be logged.
+		Logger:   log.GetLogger("slow-query"),
+	})
+
+	// NOOP query.
+	e.Exec("SELECT 1 WHERE false;")
+
+	_, stopped = lc.Check(100 * time.Millisecond)
+	assert.True(t, stopped)
+}

modules/setting/database.go

@@ -44,6 +44,7 @@ var (
 		ConnMaxLifetime   time.Duration
 		IterateBufferSize int
 		AutoMigration     bool
+		SlowQueryTreshold time.Duration
 	}{
 		Timeout:           500,
 		IterateBufferSize: 50,
@@ -86,6 +87,7 @@ func loadDBSetting(rootCfg ConfigProvider) {
 	Database.DBConnectRetries = sec.Key("DB_RETRIES").MustInt(10)
 	Database.DBConnectBackoff = sec.Key("DB_RETRY_BACKOFF").MustDuration(3 * time.Second)
 	Database.AutoMigration = sec.Key("AUTO_MIGRATION").MustBool(true)
+	Database.SlowQueryTreshold = sec.Key("SLOW_QUERY_TRESHOLD").MustDuration(5 * time.Second)
 }
 
 // DBConnStr returns database connection string