Extension Configuration (ext_conf_template.txt)

-- optional

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

Syntax

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 Constants section in TypoScript Reference. This syntax applies to the comment line that should be placed just before the constant. Consider the following example (taken from system extension "backend"):

# cat=Login; type=string; label=Logo: If set, this logo will be used instead of...
loginLogo =

First a category (cat) is defined ("Login"). 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 Settings module:

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".

Available option types

Option type	Description
boolean	checkbox
color	colorpicker
int	integer value
int+	positive integer value
integer	integer value
offset	offset
options	option select
small	small text field
string	text field
user	user function
wrap	wrap field

Option select can be used as follows:

# cat=basic/enable/050; type=options[label1=value1,label2]; label=MyLabel
myVariable = 1

Where user functions have to be written the following way:

# cat=basic/enable/050; type=user[Vendor\MyExtensionKey\ViewHelpers\MyConfigurationClass->render]; label=MyLabel
myVariable = 1

Accessing saved options

When saved in the Settings module, the configuration will be kept in the LocalConfiguration.php file and is available as array $GLOBALS['TYPO3_CONF_VARS']['EXTENSIONS']['your_extension_key'].

To retrieve the configuration use the API provided by the \TYPO3\CMS\Core\Configuration\ExtensionConfiguration class:

$backendConfiguration = \TYPO3\CMS\Core\Utility\GeneralUtility::makeInstance(ExtensionConfiguration::class)
   ->get('your_extension_key');

This will return the whole configuration as an array.

To directly fetch specific values like temporaryDirectory from the example above:

$backendConfiguration = \TYPO3\CMS\Core\Utility\GeneralUtility::makeInstance(ExtensionConfiguration::class)
   ->get('your_extension_key', 'temporaryDirectory');

Nested structure

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 = $GLOBALS['TYPO3_CONF_VARS']['EXTENSIONS']['your_extension_key'];
$extensionConfiguration['directories.']['tmp']
$extensionConfiguration['directories.']['cache']

重要

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.