Last Modified 2011-09-16 by Ralf Lang

H4 Conversion HowTo

Items that need to be converted...


Remove AUTH_HANDLER - use Horde_Registry::appInit() 'authentication' option instead.
Remove $session_control - use Horde_Registry::appInit() 'session_control' option instead
Most static Horde_Auth:: functions moved to Horde_Registry::

Horde_Auth::getAuth() -> $registry->getAuth()
Horde_Auth::getBareAuth() -> $registry->getAuth('bare')
Horde_Auth::getAuthDomain() -> $registry->getAuth('domain')
Horde_Auth::getOriginalAuth() -> $registry->getAuth('original')
Horde_Auth::getCredential() -> $registry->getAuthCredential()
Horde_Auth::isAdmin() -> $registry->isAdmin()
Horde_Auth::addHook($user) -> $registry->convertUsername($user, true)
Horde_Auth::removeHook($user) -> $registry->convertUsername($user, false)


Convert files/libraries to be able to be autoloaded.
Remove require/include calls within the code.

Class naming

All (framework) classes must be prefixed with Horde_ to allow autoloading of the files. When converting from Horde 3 format (e.g. Foo class) to Horde 4 format (e.g. Horde_Foo), the following commands are useful to convert all files automatically:

find . -type f \( ! -wholename "./.git/*" ! -name "CHANGES" \) | xargs grep -l '[] (!)]Foo::' | xargs sed -i -r -e 's/([\ \(\^\!\)])Foo::/\1Horde_Foo::/g'
find . -type f \( ! -wholename "./.git/*" ! -name "CHANGES" \) | xargs grep -l '&Foo::' | xargs sed -i -r -e 's/&Foo::/Horde_Foo::/g'
find . -type f \( ! -wholename "./.git/*" ! -name "CHANGES" \) | xargs grep -l '^Foo::' | xargs sed -i -r -e 's/^Foo::/Horde_Foo::/g'


Use Horde_Registry::appInit(), with the 'cli' option, to initialize CLI scripts.

Configuration files

Add $Id$ tag to all conf/*.xml files

Convert Base files

No more lib/base.php, lib/api.php, lib/version.php. Converted to lib/Application.php and lib/Api.php

Convert to PHP 5

instanceof instead of is_a()

CVS remnants

No need for $Horde$ in header comments.
Remove CVS directories.
Remove .cvsignore


Constants should be namespaced - preferably within the utility class (e.g. lib/App.php).


Update documentation.


All database abstraction is done through the Horde_Db library now. SQL scripts from scripts/sql/ need to be converted to Horde_Db migrations in migration/.

Cheat sheet for converting PEAR::DB calls to Horde_Db calls:

PEAR DB Horde_Db
select()/query() execute()/insert()/update()/delete()
getAll() (w/DB_FETCHMODE_ASSOC) selectAll()
getAssoc() selectAssoc() (only with 2 columns)
getCol() selectValues()
getOne() selectValue()
getRow() selectOne()
setLimit() addLimitOffset()

select() return a statement object from the SQL query.

Error Handling

Don't use Horde::fatal() directly - throw an Exception and if uncaught, a fatal exception handler will be triggered.


Remove all use of globals within the application (use injector instead).

Header templates

Most applications should no longer need a custom header template. Instead use:

require $registry->get('templates', 'horde') . '/common-header.inc';


Hooks are methods of an App_Hooks class in config/hook.php.dist now. They are called different too:

try {
    Horde::callHook('hookname', array($arg1, $arg2, ...), 'applicationname');
} catch (Horde_Exception_HookNotSet $e) {

If the hook is supposed to be called often, it should be checked if the code exists with Horde::hookExists() instead of catching the Horde_Exception_HookNotSet exception.



$registry->getImageDir() . '/image.png';



Note that if you want to prevent using images from Horde itself and always use the current application, use the following:

Horde_Themes::img('image.png'), array('nohorde' => true));

Also note this policy change from H3:
"Do note that doing something like grabbing an image dir and then manually appending various image names to it is NOT supported in H4."

Generating <img> tags of non-static images, e.g. the script files from horde/services/images/ through Horde::img() is not supported anymore.


Controller scripts are now initialized by:

require_once dirname(__FILE__) . '/lib/Application.php';

Injector Usage

Various Horde libraries now must be loaded via the injector.


ALL javascript should be in js/. NO javscript (if at all possible) should be contained in scripts/templates.

Log handling

Log constants have changed: we no longer use the PEAR constants and instead use strings to indicate the severity.
Also note the function signature no longer requires the file name or line number.


Horde::logMessage("Something broke", __FILE__, __LINE__, PEAR_LOG_ERR);


Horde::logMessage("Something broke", 'ERR');

Mail library

PEAR's Mail library has been replaced by Horde_Mail.


The menu should be provided now by Appname_Application::menu(). templates/menu.inc can be removed, unless there are any custom elements. To render the menu use:

echo Horde::menu();
$notification->notify(array('listeners' => 'status'));

MIME library

The MIME library has been rewritten - most calls to the library will probably need to be changed.

NLS/Language/Charset handling

Most/all language and/or charset handling has been moved to Horde_Registry. See http://bugs.horde.org/ticket/9124#c8.

Output buffering

Convert from Util::bufferOutput() -> Horde::startBuffer()/Horde::endBuffer()


Remove PEAR_Error usage - convert to Exceptions.
Each application should define a APP_Exception library that extends Horde_Exception.

Prefs UI

No more lib/prefs.php - now uses Horde_Registry_Application calls.
Update config/prefs.php to remove unneeded entries.

Sidebar integration

The sidebar menu is no longer in a separate frame. To integrate with all pages of your application, put the following code after your menu, e.g. at the bottom of templates/menu.inc, but before the notification output:

if (!Horde_Util::getFormData('ajaxui')) require HORDE_BASE . '/services/sidebar.php';

Test script

No longer uses test.php - converted to lib/Test.php.




All translations and help files have to be encoded in UTF-8 now. Translation files have been renamed and moved to the locale/ directories. imp/po/de_DE.po is now in imp/locale/de/LC_MESSAGES/imp.po.


Horde_Ui_* classes are now Horde_Core_Ui_*

Url generation

Use Horde::url() instead of Horde::applicationUrl().
Use Horde_Url:: instead of Horde_Util::addParameter()/Horde_Util::removeParameter().