bookmark_borderPEAR down – Taking Horde to Composer

Since Horde 4, the Horde ecosystem heavily relied on the PEAR infrastructure. Sadly, this infrastructure is in bad health. It’s time to add alternatives.

Everybody has noticed the recent PEAR break-in.

A security breach has been found on the http://pear.php.net webserver, with a tainted go-pear.phar discovered. The PEAR website itself has been disabled until a known clean site can be rebuilt. A more detailed announcement will be on the PEAR Blog once it’s back online. If you have downloaded this go-pear.phar in the past six months, you should get a new copy of the same release version from GitHub (pear/pearweb_phars) and compare file hashes. If different, you may have the infected file.

While I am writing these lines, pear.php.net is down. Retrieval links for individual pear packages are down. Installation of pear packages is still possible from private mirrors or linux software distribution packages (openSUSE, Debian, Ubuntu). Separate pear servers like pear.horde.org are not directly affected. However, a lot of pear software relies on one or many libraries from pear.php.net – it’s a tough situation. A lot of software projects have moved on to composer, an alternative solution to dependency distribution. However, some composer projects have dependency on PEAR channels.

I am currently submitting some changes to Horde upstream to make Horde libs (both released and from git) more usable from composer projects.
Short-term goal is making use of some highlight libraries easier in other contexts. For example, Horde_ActiveSync and Horde_Mail, Horde_Smtp, Horde_Imap_Client are really shiny. I use Horde_Date so much I even introduced it in some non-horde software – even though most functionality is also somewhere in php native classes.

The ultimate goal however is to enable horde groupware installations out of composer. This requires more work to be done. There are several issues.

  • The db migration tool checks for some pear path settings during runtime https://github.com/horde/Core/pull/2 Most likely there are other code paths which need to be addressed.
  • Horde Libraries should not be web readable but horde apps should be in a web accessible structure. Traditionally, they are installed below the base application (“horde dir”) but they can also be installed to separate dirs.
  • Some libraries like Horde_Core contain files like javascript packages which need to be moved or linked to a location inside another package. Traditionally, this is handled either by the “git-tools” tool linking the code directory to a separate web directory or by pear placing various parts of the package to different root paths. Composer doesn’t have that out of the box.

Horde already has been generating composer manifest files for quite a while. Unfortunately, they were thin wrappers around the existing pear channel. The original generator even took all package information from the pear manifest file (package.xml) and converted it. Which means, it relied on a working pear installation. I wrote an alternative implementation which directly converts from .horde.yml to composer.json – Calling the packages by their composer-native names. As horde packages have not been released on packagist yet, the composer manifest also includes repository links to the relevant git repository. This should later be disabled for releases and only turned on in master/head scenarios. Releases should be pulled from packagist authority, which is much faster and less reliant on existing repository layouts. https://github.com/horde/components/pull/3

To address the open points, composer needs to be amended. I currently generate the manifests using package types “horde-library” and “horde-application” – I also added a package type “horde-theme” for which no precedent exists yet. Composer doesn’t understand these types unless one adds an installer plugin https://github.com/maintaina-com/installers. Once completed and accepted, this should be upstreamed into composer/installers. The plugin currently handles installing apps to appropriate places rather than /vendor/ – however, I think we should avoid having a super-special case “horde-base” and default to installing apps directly below the project dir. Horde base should also live on the same hierarchy. This needs some additional tools and autoconfiguration to make it convenient. Still much way to go.

That said, I don’t think pear support should be dropped anytime soon. It’s the most sensible way for distribution packaging php software. As long as we can bear the cost involved in keeping it up, we should try.