解决嵌套事务使用不当（rollback之后不抛出捕获到的异常）时，回滚后事务还被提交的问题

windwork · Sep 21, 2017 · 480a4e3 · 480a4e3
1 parent 25b59a9
commit 480a4e3
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Showing 6 changed files with 235 additions and 66 deletions.
diff --git a/lib/DBAbstract.php b/lib/DBAbstract.php
@@ -30,6 +30,13 @@ abstract class DBAbstract implements DBInterface
      * @var int
      */
     protected $transactions = 0;
+
+    /**
+     * 事务链中还应继续执行回滚
+     * 在嵌套事务中，开启多少次事务就应该执行多少次回滚
+     * @var int
+     */
+    protected $rollbackAgain = false;
 
     /**
      * 记录当前请求执行的SQL查询语句

diff --git a/lib/Finder.php b/lib/Finder.php
@@ -82,8 +82,6 @@ public function fetchAll($offset = 0, $rows = 0)
             } else {
                 $opts['limit'] = "{$offset}";
             }
-        } else {
-            throw new Exception('param error, one of the params must be greater than 0');
         }
 
         $sql = QueryBuilder::optionsToSql($opts);

diff --git a/lib/adapter/MySQLi.php b/lib/adapter/MySQLi.php
@@ -69,11 +69,19 @@ public function beginTransaction()
      */
     public function commit()
     {
+        if ($this->rollbackAgain) {
+            throw new \wf\db\Exception('Please throw exception after rollback in last catch block');
+        }
+
         --$this->transactions;
 
         if($this->transactions == 0 && false === $this->mysqli->commit()) {
             throw new \wf\db\Exception('transaction commit error: ' . $this->getLastErr());
         }
+
+        if ($this->transactions < 0) {
+            $this->transactions = 0;
+        }
     }
 
     /**
@@ -201,9 +209,17 @@ public function setAutoCommit($isAutoCommit = false)
      */
     public function rollback()
     {
-        --$this->transactions;
-
-        if ($this->transactions <= 0 && false === $this->mysqli->rollback()) {                
+
+        // 事务链中一旦出现异常，为避免事务链中异常后面的SQL还执行，应返回到第一个事务再回滚
+        if ($this->transactions -- > 1) {
+            $this->rollbackAgain = true;
+            return;
+        }
+
+        $this->rollbackAgain = false;
+
+        // 出现异常立即回滚，回滚后再出现commit则应该抛出异常
+        if (false === $this->mysqli->rollback()) {
             throw new \wf\db\Exception('transaction rollback error: '.$this->getLastErr());
         }
     }

diff --git a/lib/adapter/PDOMySQL.php b/lib/adapter/PDOMySQL.php
@@ -72,11 +72,19 @@ public function beginTransaction()
      */
     public function commit()
     {
+        if ($this->rollbackAgain) {
+            throw new \wf\db\Exception('Please throw exception after rollback in last catch block');
+        }
+
         --$this->transactions;
 
         if($this->transactions == 0 && false === $this->dbh->commit()) {
             throw new \wf\db\Exception('transaction commit error: ' . $this->getLastErr());
         }
+
+        if ($this->transactions < 0) {
+            $this->transactions = 0;
+        }
     }
 
     /**
@@ -211,9 +219,16 @@ public function setAutoCommit($isAutoCommit = false)
      */
     public function rollback()
     {
-        --$this->transactions;
-
-        if ($this->transactions <= 0 && false === $this->dbh->rollback()) {
+        // 事务链中一旦出现异常，为避免事务链中异常后面的SQL还执行，应返回到第一个事务再回滚
+        if ($this->transactions -- > 1) {
+            $this->rollbackAgain = true;
+            return;
+        }
+
+        $this->rollbackAgain = false;
+
+        // 出现异常立即回滚，回滚后再出现commit则应该抛出异常
+        if (false === $this->dbh->rollback()) {
             throw new \wf\db\Exception('transaction rollback error: ' . $this->getLastErr());
         }
     }

diff --git a/test/MySQLiTest.php b/test/MySQLiTest.php
@@ -14,7 +14,7 @@
 /**
  * PDOMySQL test case.
  */
-class MySQLTest extends PHPUnit_Framework_TestCase 
+class MySQLiTest extends PHPUnit_Framework_TestCase
 {
     /**
      * 
@@ -203,5 +203,73 @@ public function testRollBack()
         $lastStr = $this->mySQLi->getColumn("SELECT str FROM wk_test_table ORDER BY id DESC");
         $this->assertEquals($uniqe, $lastStr);
     }
+
+
+    /**
+     * 测试嵌套事务
+     */
+    public function testNestedTrans()
+    {
+        $uniqe = uniqid();
+        $this->insertRow($uniqe);
+
+        try {
+            $trans = $this->mySQLi->beginTransaction();
+            $this->insertRow();
+            $this->insertRow();
+
+            try {
+                $trans = $this->mySQLi->beginTransaction();
+                $this->insertRow();
+                $this->insertRow();
+                $trans->commit();
+            } catch (\wf\db\Exception $e) {
+                $trans->rollback();
+            }
+
+            try {
+                $trans = $this->mySQLi->beginTransaction();
+                $this->insertRow();
+                $this->insertRow();
+
+                try {
+                    $trans = $this->mySQLi->beginTransaction();
+                    $this->insertRow();
+                    $this->insertRow();
+
+                    // 在此出现异常
+                    throw new \wf\db\Exception('~');
+
+                    $trans->commit();
+                } catch (\wf\db\Exception $e) {
+                    $trans->rollback();
+                }
+
+                // 应避免：事务因异常关闭，因上面回滚后没有再抛出异常，导致继续执行这里
+                $this->insertRow();
+
+                $trans->commit();
+            } catch (\wf\db\Exception $e) {
+                $trans->rollback();
+            }
+
+            $trans->commit();
+        } catch (\wf\db\Exception $e) {
+            $trans->rollback();
+        }
+
+        // 检测事务没有添加成功（最后添加的是事务开启前的）
+        $lastStr = $this->mySQLi->getColumn("SELECT str FROM wk_test_table ORDER BY id DESC");
+        $this->assertEquals($uniqe, $lastStr);
+
+
+        // 检查事务已正常关闭
+        $uniqe = uniqid();
+        $this->insertRow($uniqe);
+        $lastStr = $this->mySQLi->getColumn("SELECT str FROM wk_test_table ORDER BY id DESC");
+        $this->assertEquals($uniqe, $lastStr);
+
+        print 'testNestedTrans done';
+    }
 }