Directory, Icon and Controller

Directory Name

When creating a package, first choose how you're going to name its outer directory. This directory name should be all lower case, with no spaces. If you want to separate something, place an underscore between its two strings. This is exactly how other items like block types and themes work. For example, if your package is named "Hello World" you might choose to make its directory name "hello_world".

Icon

A file named icon.png may be present at the root level in your package controller. Historically this has been a 97px by 97px icon in the PNG format, but in Concrete CMS version 7 and above this may be any size, as long as its square in its aspect ratio (note: there won't be much to gain by making this file larger than 200 pixels, as it's only displayed at a pretty small size.)

Controller

Finally, every package has a controller.php file in its base directory. This file contains the information needed for your system to identify the package, install it, uninstall it, and optional custom code that this package adds to the Concrete startup routine. All other logic relating to what your package actually does should be located elsewhere. Here is an example package controller for a package that does nothing but install a custom block type.

<?php
namespace Concrete\Package\DocumentLibrary;

defined('C5_EXECUTE') or die('Access Denied.');

use \Concrete\Core\Package\Package;
use \Concrete\Core\Block\BlockType\BlockType;

class Controller extends Package
{
    protected $pkgHandle = 'document_library';
    protected $appVersionRequired = '5.7.4.3b1';
    protected $pkgVersion = '1.0';

    public function getPackageDescription()
    {
        return t('Adds a searchable file library to a page.');
    }

    public function getPackageName()
    {
        return t('Document Library');
    }

    public function install()
    {
        $pkg = parent::install();
        BlockType::installBlockType('document_library', $pkg);
    }
}

This file is very straightforward. First, we namespace it appropriately. All items within a Concrete package will begin with the Concrete\Package namespace, with the segment immediately following being the camelCased version of their package directory name. In this case, this package directory name is "document_library", so the namespace is Concrete\Package\DocumentLibrary.

Note: the namespace and package directory name must match after this transformation. If not, the package will appear to be listed as Unknown Package with a notice that it is a broken package which can't be installed:

Next, we take care of making sure this file can't be browsed to directly in the browser with this line:

defined('C5_EXECUTE') or die('Access Denied.');

Then, we import the two additional classes outside the package namespace that we're going to need. We need these because we're going to use the BlockType class to add a block type during installation, and we need the base Concrete\Core\Package\Package class because our package controller extends this base class.

After that, we specify the package's controller, which is the only class in this file. The package's controller is always named "Controller" – this works because it's present in a custom namespace. It also always extends from Concrete\Core\Package\Package.

The three protected variables in this class are required by packages. (Note: there are other protected variables you could add to this package to provide additional functionality and behavior, but they're not required and we'll worry about them later.) These are:

  • $pkgHandle: This is the "handle" for your package. It is a unique, string-based identifier for your package. It must match your package's directory name exactly.
  • $appVersionRequired: This is the minimum version of Concrete required by your package. If this package is installed on a version of Concrete that is lower than this version, an error will be displayed and installation will not continue.
  • $pkgVersion: This is the version number for this package. **This can be any value, as long as its a version number format that PHP's version_compare function supports. You do not need to begin with 1.0, for example. This version number is used to provide upgrade options. For example, if you install version 1.0 of a package, and then replace the package directory with a package with a controller.php file stating its version is 1.5, you'll be presented with an update notice in the Dashboard, and you'll be able to upgrade the package.

Next, we have two methods that provide more data about the package to Concrete.

  • getPackageDescription(): This method provides a short description about the package to Concrete. This is displayed in the Dashboard.
  • getPackageName(): This method provides the name of the package to Concrete. This is displayed in the Dashboard.

Finally, in the install() method defines what gets installed when this package is installed.