UPGRADE.md

Contao Open Source CMS API changes

Version 3.4 to 3.5

StringUtil class

Since the String class is not compatible with PHP 7, we have renamed it to StringUtil. The String class remains available for reasons of backwards compatibility, however it has been deprecated and will be removed in a future version.

PHP version

The minimum PHP version is raised from 5.3.7 to 5.4.0.

DataContainer

The DataContainer class is now abstract, which however should not matter, because the contructor has been protected ever since. Also, the methods getPalette() and save() have been added as abstract methods, which need to be implemented by all child classes (already the case in the DC_ classes).

Version 3.3 to 3.4

PHP version

We are using a new Blowfish mode that deals with potential high-bit attacks in Contao 3.4, therefore the minimum PHP version is raised from 5.3.2 to 5.3.7.

Version 3.2 to 3.3

processFormData hook

The "processFormData" hook now passes $arrSubmitted as first argument instead of $_SESSION['FORM_DATA']. This is actually a bug fix, because so far the hook passed everything that was stored in the session instead of just the fields of the current form.

However, the change implies a backwards compatibility break, because the former implementation allowed to add form fields by modifying $arrData:

public function myProcessFormData(&$arrData, …) {
    $arrData['new_field'] = 'new_value';
}

In version 3.3, you have to add to $_SESSION['FORM_DATA'] instead:

public function myProcessFormData($arrData, …) {
    $_SESSION['FORM_DATA']['new_field'] = 'new_value';
}

Version 3.1 to 3.2

Controller::addImageToTemplate()

Before Contao 3.2.2, the addImageToTemplate() method would override the "href" property with the image URL or link target even if the property was set already. This was causing issues in the event templates, which use the "href" property to store the event details URL.

Therefore, if the "href" property is set, the addImageToTemplate() method will store the image URL or link target in the "imageHref" property instead. However, this requires to adjust custom event_* templates which render the event image. Note that this does not affect the core templates.

Usage before version 3.2.2:

<h2><a href="<?php echo $this->href; ?>Event title</a></h2>
<p><a href="<?php echo $this->href; ?>"><img src="..."></a></p>

New usage as of version 3.2.2:

<h2><a href="<?php echo $this->href; ?>Event title</a></h2>
<p><a href="<?php echo $this->imageHref; ?>"><img src="..."></a></p>

buttons_callback

The "buttons_callback" was introduced in Contao 3.0 to add custom buttons when selecting multiple records for editing. In Contao 3.2 this behavior has been enhanced in a way that not only the selection buttons but any button set can be altered as well as existing buttons can be removed.

We have decided to use the existing "buttons_callback" for this, because it does not make sense to add another hook which essentially does the same. However, this decision implies a backwards compatibilty break, since the API of the hook has had to change as described below.

Usage in Contao 3.0 and 3.1:

$GLOBALS['TL_DCA']['tl_page']['edit'] => array
(
    'buttons_callback' => array
    (
        array('tl_page', 'addAliasButton')
    )
);

/**
 * Button callback
 * @return string
 */
public function addAliasButton()
{
    return '<input...';
}

New usage as of Contao 3.2:

// Add a button to the "select multiple" screen
$GLOBALS['TL_DCA']['tl_page']['select'] => array
(
    'buttons_callback' => array
    (
        array('tl_page', 'addAliasButton')
    )
);

// Add a button to the "edit record(s)" screen
$GLOBALS['TL_DCA']['tl_page']['edit'] => array
(
    'buttons_callback' => array
    (
        array('tl_page', 'addAliasButton')
    )
);

/**
 * Button callback
 * @param array
 * @return array
 */
public function addAliasButton($arrButtons)
{
    // Unset the save button
    unset($arrButtons['edit']);

    // Add a custom "alias" button
    $arrButtons['alias'] = '<input … >';

    // Return the array of buttons
    return $arrButtons;
}

In case you have been using the "buttons_callback", please make sure to adjust your extension accordingly.

Model::save()

In Contao 3.0 and 3.1 it was possible to create two models for the same database record by passing true to the Model::save() method. However, this could lead to a loss of data in certain edge-cases, so we have decided to implement a model registry to ensure that there is only one model per database record.

The registry, however, requires to use the clone command to duplicate models, therefore the $blnForceInsert argment had to be removed. If you have used it in your custom extension, be sure to adjust the code accordingly.

Usage in Contao 3.0 and 3.1:

$objPage = PageModel::findByPk(1);
$objPage->title = 'New page title';
$objPage->save(true);

New usage as of Contao 3.2:

$objPage = PageModel::findByPk(1);
$objCopy = clone $objPage;
$objCopy->title = 'New page title';
$objCopy->save();