PHP Code Deployment Tips
I would suggest making your testing deployment strategy a production-ready install-script -- since you're going to need one of those anyway eventually.
A few tips that may seem obvious to some, but are worth pointing out:
- Your config file saved in your VCS should be a template, and should be named differently from the file that will eventually contain the actual settings. E.g.
config-dist.phporconfig-sample.conforsample/config-mysql.phpor something along those lines. Otherwise you will end up accidentally checking in a server-specific configuration file over your template. - For PHP deployment, anticipate that some users will not be able to run server-side scripts through any mechanism other than the web server itself. A PHP-based installer is almost non-negotiable.
- You should include a consumer-friendly update mechanism, and for that, wordpress is a great example of a project to emulate. A PHP script can (a) download the latest build, (b) use the ftp functions to update your application's files, and (c) execute an update script which makes the appropriate changes to the database, etc.
- For heaven's sake don't do like [redacted] and make your users download and install separate patches for each point release. Have them download the latest (final) release which contains all the updates to date, and applies the correct
ALTER TABLEfunctions in sequence.
Whether the files are deployed via SVN or through FTP, the install/update mechanism should be the same: get the latest files, run the update script. The updater uses the version listed in the PHP script and the version listed in the DB, and uses that knowledge to apply the appropriate DB patches in order. As for how to generate those patches, there are other questions here that you can refer to for more info.
As for the "Maintenance" page, just use the version trick mentioned above to trigger it (compare the version in the DB against the version in the PHP code). It's also useful to be able to mark a site as "down" to the public but make it visible to admins (like Joomla does), which you can trigger through database or filesystem flags.
As for automatically pulling code from SVN, I'd say you're better off with either a cron script or with commit triggers than working that into your application, since it wouldn't be relevant to end users.
This isn't exactly part of your question, but it's relevant:
If you go into distributing code intended for a wide audience, I would advise you to go with building and distributing OpenSSL-signed PHAR packages. You can distribute them over HTTP without a problem, and because they're OpenSSL-signed, you're also mitigating the risk of man-in-the-middle attacks and protecting end-users/customers/clients from someone injecting code if you want to setup an automatic or one-click update.
There's a set of tools I've contributed to in the past that work great for this, but you'll either need PHP 5.3, or you'll need PHP 5.2 with PHAR installed via PECL. https://github.com/koto/phar-util
As far as testing goes, PHPUnit is the de facto standard.
If you are interested in using Git then you should check out this build system from CodeMeme. From what you described it sounds like it would be a good fit. You can add it to any project as a submodule and with the included code you can tailor a build script that will deploy to different multiple servers in multiple environments. It uses Git to build the code for deployment but unfortunately SVN is not supported.