Configuration options

In the ext_conf_template.txt file configuration options for an extension can be defined. They will be accessible in the TYPO3 backend from the Extension Manager.

There's a specific syntax to declare these options properly, which is similar to the one used for TypoScript constants (see "Declaring constants for the Constant editor" in "TypoScript Syntax and In-depth Study"). This syntax applies to the comment line that should be placed just before the constant. Consider the following example (taken from system extension "rsaauth"):

# cat=basic/enable; type=string; label=Path to the temporary directory:This directory will contain...
temporaryDirectory =

First a category (cat) is defined ("basic") with the subcategory "enable". Then a type is given ("string") and finally a label, which is itself split (on the colon ":") into a title and a description (this should actually be a localized string). The above example will be rendered like this in the EM:

Configuration screen for the rsaauth extension

The configuration tab displays all options from a single category. A selector is available to switch between categories. Inside an option screen, options are grouped by subcategory. At the bottom of the screenshot, the label – split between header and description – is visible. Then comes the field itself, in this case an input, because the option's type is "string".

Once you saved the configuration in the ExtensionManager, it will be stored in $GLOBALS['TYPO3_CONF_VARS']['EXT']['extConf']['your_extension_key'] as a serialized array.

To fetch the value of temporaryDirectory from the example above, you could simply use:

$extensionConfiguration = unserialize($GLOBALS['TYPO3_CONF_VARS']['EXT']['extConf']['your_extension_key']);
$temporaryDirectory = $extensionConfiguration['temporaryDirectory'];

Or even better use the API to get the information merged with the default settings if the settings have not been saved yet:

/** @var \TYPO3\CMS\Extensionmanager\Utility\ConfigurationUtility $configurationUtility */
$configurationUtility = $this->objectManager->get('TYPO3\CMS\Extensionmanager\Utility\ConfigurationUtility');
$extensionConfiguration = $configurationUtility->getCurrentConfiguration('themes');

You can also define nested options using the TypoScript notation:

directories {
   # cat=basic/enable; type=string; label=Path to the temporary directory
   tmp =
   # cat=basic/enable; type=string; label=Path to the cache directory
   cache =
}

This will result in a multidimensional array:

$extensionConfiguration = unserialize($GLOBALS['TYPO3_CONF_VARS']['EXT']['extConf']['your_extension_key']);
$extensionConfiguration['directories.']['tmp']
$extensionConfiguration['directories.']['cache']

Important

Notice the dot at the end of the directories key. This notation must be used for every grouping key and is a convention of the TypoScript parser.