From 5dd2bb482755f5e8eb5ecaff39e675fb62f19a20 Mon Sep 17 00:00:00 2001
From: Cr <631807682@qq.com>
Date: Wed, 19 Oct 2022 14:46:59 +0800
Subject: [PATCH] feat(PreparedStmtDB): support reset (#5782)

* feat(PreparedStmtDB): support reset

* fix: close all stmt

* test: fix test

* fix: delete one by one
---
 prepare_stmt.go             | 12 ++++++++++++
 tests/prepared_stmt_test.go | 28 +++++++++++++++++++++++++++-
 2 files changed, 39 insertions(+), 1 deletion(-)

diff --git a/prepare_stmt.go b/prepare_stmt.go
index 3934bb97..7591e533 100644
--- a/prepare_stmt.go
+++ b/prepare_stmt.go
@@ -44,6 +44,18 @@ func (db *PreparedStmtDB) Close() {
 	}
 }
 
+func (db *PreparedStmtDB) Reset() {
+	db.Mux.Lock()
+	defer db.Mux.Unlock()
+	for query, stmt := range db.Stmts {
+		delete(db.Stmts, query)
+		go stmt.Close()
+	}
+
+	db.PreparedSQL = make([]string, 0, 100)
+	db.Stmts = map[string](*Stmt){}
+}
+
 func (db *PreparedStmtDB) prepare(ctx context.Context, conn ConnPool, isTransaction bool, query string) (Stmt, error) {
 	db.Mux.RLock()
 	if stmt, ok := db.Stmts[query]; ok && (!stmt.Transaction || isTransaction) {
diff --git a/tests/prepared_stmt_test.go b/tests/prepared_stmt_test.go
index c7f251f2..64baa01b 100644
--- a/tests/prepared_stmt_test.go
+++ b/tests/prepared_stmt_test.go
@@ -2,8 +2,8 @@ package tests_test
 
 import (
 	"context"
-	"sync"
 	"errors"
+	"sync"
 	"testing"
 	"time"
 
@@ -168,3 +168,29 @@ func TestPreparedStmtInTransaction(t *testing.T) {
 		t.Errorf("Failed, got error: %v", err)
 	}
 }
+
+func TestPreparedStmtReset(t *testing.T) {
+	tx := DB.Session(&gorm.Session{PrepareStmt: true})
+
+	user := *GetUser("prepared_stmt_reset", Config{})
+	tx = tx.Create(&user)
+
+	pdb, ok := tx.ConnPool.(*gorm.PreparedStmtDB)
+	if !ok {
+		t.Fatalf("should assign PreparedStatement Manager back to database when using PrepareStmt mode")
+	}
+
+	pdb.Mux.Lock()
+	if len(pdb.Stmts) == 0 {
+		pdb.Mux.Unlock()
+		t.Fatalf("prepared stmt can not be empty")
+	}
+	pdb.Mux.Unlock()
+
+	pdb.Reset()
+	pdb.Mux.Lock()
+	defer pdb.Mux.Unlock()
+	if len(pdb.Stmts) != 0 {
+		t.Fatalf("prepared stmt should be empty")
+	}
+}