add identity and lock

[m6w6/pq-gateway] / lib / pq / Gateway / Table / OptimisticLock.php

diff --git a/lib/pq/Gateway/Table/OptimisticLock.php b/lib/pq/Gateway/Table/OptimisticLock.php
new file mode 100644 (file)
index 0000000..08e5ae3
--- /dev/null
+++ b/lib/pq/Gateway/Table/OptimisticLock.php
@@ -0,0 +1,34 @@
+<?php
+
+namespace pq\Gateway\Table;
+
+use \pq\Gateway\Row;
+
+/**
+ * An optimistic row lock implementation using a versioning column
+ */
+class OptimisticLock implements LockInterface
+{
+       /**
+        * The name of the versioning column
+        * @var string
+        */
+       protected $column;
+       
+       /**
+        * @param string $column
+        */
+       function __construct($column = "version") {
+               $this->column = $column;
+       }
+       
+       /**
+        * @implements LockInterface
+        * @param \pq\Gateway\Row $row
+        * @param array $where reference to the criteria
+        */
+       function criteria(Row $row, array &$where) {
+               $where["{$this->column}="] = $row->getData()[$this->column];
+               $row->{$this->column}->mod(+1);
+       }
+}