Images in Magento widgets

Question

I am developing a site for a fashion client in Magento Community version 1.4.2 and as part of this project I need to have some customized home page promotion blocks to feature specific products or categories of products. For this I thought I would write my own widget and have made pretty good progress in this with the exception of how to deal with images. I need to include an image as part of the promotion. In my widget definition file I included the following parameter

        <image>
            <label>Image</label>
            <description>Promotion image</description>
            <visible>1</visible>
            <type>image</type>
        </image>

This seemed at first to work fine and when creating/editing a widget in the admin back end a file upload field is included in the widget options however on saving the form the image does not appear to be uploaded, or its details retained in the database. Does anyone else have experience of using images in widgets and what I may be doing wrong?

Answer 1

There are a couple reason why it doesn't save/upload the image:

• The form enctype needs to be "multipart/form-data" for a file upload to work
• Even if you change the form enctype to "multipart/form-data" you will notice if you monitor the requests that it gets POST'ed as "application/x-www-form-urlencoded" this is because it is done through ajax and ajax by itself can't process a file upload, you need to process them separately.

I have successfully implemented a "Insert Image" button which initialises the Media Library dialogue where you can browse your server for images and/or upload images.

Once the user clicks "Insert File" it inserts the full image url into a textbox in the widget so it's passed along like a normal field to your template.

This is how I achieved it:

In your widget.xml specify a new node:

<image translate="label">
    <label>Image</label>
    <visible>1</visible>
    <required>1</required>
    <type>label</type>
    <helper_block>
        <type>widgets/cms_wysiwyg_images_chooser</type>
        <data>
            <button translate="open">
                <open>Insert Image...</open>
            </button>
        </data>
    </helper_block>
</image>

The helper block type <type>widgets/cms_wysiwyg_images_chooser</type> is a custom class, so you can change it to anything you want as long as you create the class/files correctly.

<?php
class Stackoverflow_Widgets_Block_Cms_Wysiwyg_Images_Chooser extends Mage_Adminhtml_Block_Template
{
public function prepareElementHtml(Varien_Data_Form_Element_Abstract $element)
{
    $config = $this->getConfig();
    $chooseButton = $this->getLayout()->createBlock('adminhtml/widget_button')
        ->setType('button')
        ->setClass('scalable btn-chooser')
        ->setLabel($config['button']['open'])
        ->setOnclick('MediabrowserUtility.openDialog(\''.$this->getUrl('*/cms_wysiwyg_images/index', array('target_element_id' => $element->getName())).'\')')
        ->setDisabled($element->getReadonly());
    $text = new Varien_Data_Form_Element_Text();
    $text->setForm($element->getForm())
        ->setId($element->getName())
        ->setName($element->getName())
        ->setClass('widget-option input-text');
    if ($element->getRequired()) {
        $text->addClass('required-entry');
    }
    if ($element->getValue()) {
        $text->setValue($element->getValue());
    }
    $element->setData('after_element_html', $text->getElementHtml().$chooseButton->toHtml());
    return $element;
}
}
?>

And that is it! You should now have a new field in your widget options called "Image" with a textbox and a button in which you can insert the url to an image on your server and display it from your template.

A quick explanation of how it works:

A button is created that has an onclick function that calls the Media Library dialogue by calling MediabrowserUtility.openDialog() which along is passed the parameter target_element_id which tells media library what element to set the value in once they user clicks "Insert File" so we simply pass along the id of our textbox in the widget for it to receive the url of the image that the user selected.

Hope this helps someone as I couldn't find any resources out there that explained how to do it so I spent quite a while digging through Magento to work it all out :)

What I would like to do in the future is have it so it displays the image after you select it in the widget, and it stores the url in a hidden field, but having an onchange bind is not fired when the value is set to the element from js/mage/adminhtml/browser.js in the insert function, so without changing the core files it is a lot harder to do. I thought about playing around with when the form gets focus again after the Media Library closes or a timer (pretty dodgey but would work), but I have other things to move on to and may come back to it later!

UPDATE:

The URL's that the Media Library generates are like so:

http://www.yourwebsite.com/index.php/admin/cms_wysiwyg/directive/___directive/e3ttZWRpYSB1cmw9Ind5c2l3eWcvd2lkZ2V0cy9iYW5uZXIvaG9tZXBhZ2UvZm9yZWdyb3VuZC9maXNoLXRhbmsucG5nIn19/key/e8167e3884e40b97d8985e7b84e7cbc7875f134e5f7e5946c9c2a482d0279762/

Which are a cached image, and only work if the user is an admin. Stupid? Yes. If you insert the same image in to a CMS page when the html is generated for output it converts it to the original url on the server accessible via /media/wysiwyg/path/to/file/photo.jpg. We need the original url to show to the user, so what we can do is hook into the function that generates the widget html (when you click "Insert Widget") and look for /admin/cms_wysiwyg/directive/___directive/ and replace it with the original URL to the image as the CMS page does.

In your config.xml for your custom widgets:

<global>
    <models>
        <widget>
            <rewrite>
                <widget>Stackoverflow_Widgets_Model_Widget</widget>
            </rewrite>
        </widget>
    </models>
</global>

Then create the model Widget code\local\Stackoverflow\Widgets\Model\Widget.php:

<?php
class Stackoverflow_Widgets_Model_Widget extends Mage_Widget_Model_Widget
{
    public function getWidgetDeclaration($type, $params = array(), $asIs = true)
    {
        foreach($params as $k => $v){
            if(strpos($v,'/admin/cms_wysiwyg/directive/___directive/') !== false){
                $parts = explode('/',parse_url($v, PHP_URL_PATH));
                $key = array_search('___directive', $parts);
                if($key !== false){
                    $directive = $parts[$key+1];
                    $src = Mage::getModel('core/email_template_filter')->filter(Mage::helper('core')->urlDecode($directive));
                    if(!empty($src)){
                        $params[$k] = parse_url($src, PHP_URL_PATH);
                    }
                }
            }
        }
        return parent::getWidgetDeclaration($type, $params, $asIs);
    }
}

Which overrides the getWidgetDeclaration function which is called every time a the widget output is produced for a textarea/wysiwyg and looks through all the parameters and if it finds an image that is linked to the admin cache it will find out the original image and overwrite the variable in the array and call the original function with the parameters.

If the cached image is not found the function will work as normal.

UPDATE: 13/09/2012

As Jonathan Day pointed out you have to overwrite Mage_Widget_Model_Widget_Instance also if you want it to work in a Widget Instance.

I haven't had the need to add an image to a widget through a Widget Instance until now and was confused why my function didn't work, until I investigated and realised the "popup" widget instances use Mage_Widget_Model_Widget and the widget instances that are used on a Widget options tab (no popup) are Mage_Widget_Model_Widget_Instance and do not extend Mage_Widget_Model_Widget so do not inherit the functionality.

To add the functionality to Mage_Widget_Model_Widget_Instance simply add the line <widget_instance>Petbarn_Widgets_Model_Widget_Instance</widget_instance> to your config.xml so it will look like:

<global>
    <models>
        <widget>
            <rewrite>
                <widget>Stackoverflow_Widgets_Model_Widget</widget>
                <widget_instance>Stackoverflow_Widgets_Model_Widget_Instance</widget_instance>
            </rewrite>
        </widget>
    </models>
</global>

Then create the model Instance code\local\Stackoverflow\Widgets\Model\Widget\Instance.php:

<?php
class Petbarn_Widgets_Model_Widget_Instance extends Mage_Widget_Model_Widget_Instance
{
    protected function _beforeSave()
    {
        if (is_array($this->getData('widget_parameters'))) {
            $params = $this->getData('widget_parameters');
            foreach($params as $k => $v){
                if(strpos($v,'/cms_wysiwyg/directive/___directive/') !== false){
                    $parts = explode('/',parse_url($v, PHP_URL_PATH));
                    $key = array_search('___directive', $parts);
                    if($key !== false){
                        $directive = $parts[$key+1];
                        $src = Mage::getModel('core/email_template_filter')->filter(Mage::helper('core')->urlDecode($directive));
                        if(!empty($src)){
                            $params[$k] = parse_url($src, PHP_URL_PATH);
                        }
                    }
                }
            }
            $this->setData('widget_parameters', $params);
        }
        return parent::_beforeSave();
    }
}

This time we are modifying the widget_parameters data at the start of the _beforeSave() function so it fixes up the url before it saves it.

You also have to ensure the /js/mage/adminhtml/browser.js javascript file is included (in my case it wasn't) to get the MediabrowserUtility functionality.

To ensure it is included, the easiest way is to include it for all of admin (didn't spend much time targeting it better).

Create a local.xml for adminhtml layouts (if you don't already have one): app\design\adminhtml\default\default\layout\local.xml

<?xml version="1.0"?>
<layout version="0.1.0">
    <default>
        <reference name="head">
            <action method="addJs"><script>mage/adminhtml/browser.js</script></action>
        </reference>
    </default>
</layout>

This will make Magento include js/mage/adminhtml/browser.js on every page of admin so MediabrowserUtility will always be available.

NOTE: I'm using Magento Enterprise 1.11.2.0 so I'm not sure how it behaves on other versions.

Answer 2

I solved this use case by creating a custom field type for widgets:

<image>
    <label>Image</label>
    <description>Promotion image</description>
    <visible>1</visible>
    <type>widgetimagechooser/chooser</type>
</image>

I implemented a block Aijko_WidgetImageChooser_Block_Chooser that triggers the standard Magento image chooser element.

To solve the problem with the non clear url to the image file I implemented a custom controller Aijko_WidgetImageChooser_Adminhtml_Cms_Wysiwyg_Images_ChooserController that handles the return value from the Magento standard image chooser.

The value is added to a textbox in the widget. This relative url to the image then can be used to show the image in the frontend.

Feel free to try the extension available on Github or install directly using Magento Connect.

Answer 3

Thx krus for you answer! I've found a nicer way to solve the problem with the cached image URLs. I even had to do this, because your solution overwriting the Widget Model didn't work with Magento 1.7.0.2.

So what I have done is adding a new GET parameter use_file_url to the URL used for the Chooser Block:

$url    = $this->getUrl(
    '*/cms_wysiwyg_images/index',
    array(
        'target_element_id' => $element->getName(),
        'use_file_url' => 1
    )
);

This passes the GET parameter to the media browser. The next step is to pass this parameter to the onInsertAction of the Mage_Adminhtml_Cms_Wysiwyg_ImagesController. Do do this, you have to override the getOnInsertUrl() function of the Mage_Adminhtml_Block_Cms_Wysiwyg_Images_Content Block:

public function getOnInsertUrl()
{
    $useFileUrl = (int)$this->getRequest()->getParam('use_file_url', 0);
    return $this->getUrl('*/*/onInsert', array('use_file_url' => $useFileUrl));
}

Then you need to handle the new parameter in the Mage_Adminhtml_Cms_Wysiwyg_ImagesController controller:

public function onInsertAction()
{
    $useFileUrl = (int)$this->getRequest()->getParam('use_file_url', 0) == 1 ? true : false;
    $helper     = Mage::helper('cms/wysiwyg_images');
    $storeId    = $this->getRequest()->getParam('store');
    $filename   = $this->getRequest()->getParam('filename');
    $filename   = $helper->idDecode($filename);
    $asIs       = $this->getRequest()->getParam('as_is');

    Mage::helper('catalog')->setStoreId($storeId);
    $helper->setStoreId($storeId);

    if ($useFileUrl == false) {
        $image = $helper->getImageHtmlDeclaration($filename, $asIs);
    } else {
        $image = $helper->getImageMediaUrl($filename);
    }

    $this->getResponse()->setBody($image);
}

The last step is to override the Mage_Cms_Helper_Wysiwyg_Images helper and add the getImageMediaUrl() function:

public function getImageMediaUrl($filename)
{
    return $this->getCurrentUrl() . $filename;
}

I think this is a quite pretty approach, even though you have to ovverride 4 classes. But passing a GET parameter seems to be more future safe than parsing the cached URL.