I haven't tested it yet, but it seems that the installer borks with a fatal error if PHP has no DOM-XML support (see URL for a report in the support forum).
It should fail more gracefully, giving a more human-readable error message.
Version: 1.22.0
Severity: major
URL: http://www.mediawiki.org/wiki/Thread:Project:Support_desk/Fatal_error_attempting_to_run_install
See Also:
https://bugzilla.wikimedia.org/show_bug.cgi?id=47564
Confirmed the bug. If the DOM functions aren't installed in php, then it throws a fatal error:
Fatal error: Class 'DOMDocument' not found in /var/www/html/wiki/includes/LocalisationCache.php on line 542
Tested with a fresh 1.20.0 installation.
The main page that displays the "setup the wiki first" doesn't throw any error. I don't know if it's possible to catch this error from the installer before loading the localisation cache.
Still valid in git master of today.
Steps to reproduce:
Actual outcome:
A blank page. Confusion.
Expected outcome:
Some error message in the browser.
Other comments:
Looking at /var/log/httpd/error_log I see:
PHP Fatal error: Class 'DOMDocument' not found in /var/www/html/mediawiki/includes/cache/LocalisationCache.php on line 587, referer: http://localhost/mediawiki/
Confirming that after installing php-xml in Fedora via
yum install php-xml
and running
apachectl restart
and now having
php-xml.i686 0:5.4.14-1.fc18
installed, this problem does not happen anymore.
So my naive idea was to change envCheckXML() in /includes/installer/Installer.php from
if ( !function_exists( "utf8_encode" ) )
to
if ( !function_exists( 'utf8_encode' ) || !class_exists( 'DOMDocument' ) )
only to realize that these checks are only run *after* the Language setting dialog which is of course too late, as MediaWiki has already failed silently.
I assume environment checks are only done after the language dialog in order to present that page in the prefered language of the user?
Change 76663 had a related patch set uploaded by MarkAHershberger:
Install without XML support
(In reply to comment #7)
Should probably get Niklas or Siebrand to look at this patch.
hexmode: Siebrand gave a +1 on the patch.
Change 76663 abandoned by Hashar:
Install without XML support
Reason:
Abandoning for now. As I commented previously, I dont like adding yet another serialized file + bunch of code as a workaround for third parties not having the PHP extension XML.
Someone may need to test it (maybe myself if I have time) but this one may be resolved with rMW41d1fa1c3aa9d6e9e0e5f0c5455b9092833e9012