Is there a best practice for doing an INSERT into a version table when an xPDO save() occurs?

- 13 Posts
pallen Reply #1, 14 years, 1 month ago
Let's say we have a table called item. And every time the user edits an item, we call
```
$obj->save()
```
I'd like to also do an INSERT into a table with all the same columns, called item_version, which would have a column called item_id. This would allow the easy querying of the item's change history. This is essentially like having a blog post that supports versioning, such that you can view history and rollback to previous versions by setting the version field on the main record.
Seems like a common pattern, wondering how best to do this.
Would you do something like
```
$version_obj = $modx->newObject('ItemVersion', $obj->toArray());
$version_obj->save();
```
At every place in the code that saves, or is there some other best practice for accomplishing this automagically when a save occurs?

863 Posts

Lucas Reply #2, 14 years, 1 month ago

You can override the save() function in your object class file (/model/package/myobject.class.php). That way it will be executed whenever you call $obj->save().

Not tested, but to give you some idea:

<?php
class myObject extends xPDOSimpleObject {

    // override the default save behaviour
    public function save() {
        $version_obj = $this->modx->newObject('ItemVersion', $this->toArray());
        $version_obj->save();

        // as we have overridden save(), trigger save() in xPDOSimpleObject
        parent :: save();
    }
}