Implemented easer feature to reduce the DB load

callbacks/query.go

@@ -9,7 +9,6 @@ import (
 	"reflect"
 	"sort"
 	"strings"
-	"time"
 )
 
 func Query(db *gorm.DB) {
@@ -17,7 +16,6 @@ func Query(db *gorm.DB) {
 		BuildQuerySQL(db)
 
 		var _query = func(db *gorm.DB) {
-			time.Sleep(5 * time.Second)
 			if !db.DryRun && db.Error == nil {
 				rows, err := db.Statement.ConnPool.QueryContext(db.Statement.Context, db.Statement.SQL.String(), db.Statement.Vars...)
 				if err != nil {

gorm.go

@@ -58,10 +58,10 @@ type Config struct {
 	Plugins map[string]Plugin
 	// Ease database load by grouping identical queries
 	Ease      bool
+	EaseQueue *sync.Map
 
 	callbacks  *callbacks
 	cacheStore *sync.Map
-	easeQueue  *sync.Map
 }
 
 // Apply update config to new config
@@ -170,8 +170,8 @@ func Open(dialector Dialector, opts ...Option) (db *DB, err error) {
 		config.cacheStore = &sync.Map{}
 	}
 
-	if config.Ease && config.easeQueue == nil {
+	if config.Ease && config.EaseQueue == nil {
-		config.easeQueue = &sync.Map{}
+		config.EaseQueue = &sync.Map{}
 	}
 
 	db = &DB{Config: config, clone: 1}
@@ -501,13 +501,13 @@ func (db *DB) Ease(cb func(*DB)) *DB {
 	}
 	eq.wg.Add(1)
 
-	var runner, ok = db.easeQueue.LoadOrStore(hash, eq)
+	var runner, ok = db.EaseQueue.LoadOrStore(hash, eq)
 	et := runner.(*easedTask)
 
 	if !ok {
 		cb(db)
 		et.wg.Done()
-		db.easeQueue.Delete(hash)
+		db.EaseQueue.Delete(hash)
 		return db
 	}
 

tests/easer_test.go

@@ -0,0 +1,75 @@
+package tests_test
+
+import (
+	"gorm.io/gorm"
+	"sync"
+	"testing"
+	"time"
+)
+
+func TestEaser(t *testing.T) {
+	t.Run("once", func(t *testing.T) {
+		db1 := DB.Unscoped()
+		db1.Config.EaseQueue = &sync.Map{}
+
+		wg := &sync.WaitGroup{}
+		wg.Add(2)
+
+		incr := 0
+
+		testQuery := func(d *gorm.DB) {
+			time.Sleep(time.Second)
+			incr++
+		}
+
+		go func() {
+			db1.Ease(testQuery)
+			wg.Done()
+		}()
+
+		go func() {
+			time.Sleep(500 * time.Millisecond)
+			db1.Ease(testQuery)
+			wg.Done()
+		}()
+
+		wg.Wait()
+
+		if incr != 1 {
+			t.Error("easer had to run the query only once")
+		}
+	})
+	t.Run("twice", func(t *testing.T) {
+		db1 := DB.Unscoped()
+		db1.Config.EaseQueue = &sync.Map{}
+
+		wg := &sync.WaitGroup{}
+		wg.Add(2)
+
+		incr := 0
+
+		testQuery := func(d *gorm.DB) {
+			time.Sleep(time.Second)
+			incr++
+		}
+
+		go func() {
+			db1.Statement.SQL.WriteString("q1")
+			db1.Ease(testQuery)
+			wg.Done()
+		}()
+
+		go func() {
+			time.Sleep(500 * time.Millisecond)
+			db1.Statement.SQL.WriteString("q2")
+			db1.Ease(testQuery)
+			wg.Done()
+		}()
+
+		wg.Wait()
+
+		if incr != 2 {
+			t.Error("easer had to run two separate queries")
+		}
+	})
+}