Editorial

XP Release procedure

2013-05-16T18:33:31+02:00

After introducing the new build system a while ago, we've produced quite a number of releases already. Time for some documentation, now that we know the procedure works as expected.

The XP Wiki now contains a step by step howto for creating releases and release candidates. Here it is!

1.0.0 - nine years later

2012-06-22T14:12:00+02:00

Nine years ago we released XP Framework, version 1.0.0 with the following change log:

  . No more support for PHP smaller than 4.3.0
  . There is now a common subclass for Errors and Exceptions called Throwable
  . An exceptions stacktrace is an array of lang.StackTraceElement objects
  . Exception::getStackTrace() returns this array and no longer a string
  . Removes Object::getName() which has been deprecated for a while now
  . Uses xp::registry to keep the global namespace free of bullshit

Although we had already been using it in production since more than a year at that time (the "Initial revision" was on 2002-02-21), we decided not to give it a more or less "stable" version until June 22nd, 2003.

a workaround for certain PHP versions with a broken CRC32b implementation, hiding it transparently from the user. In other places like the lang.Process class, we take care of platform differences, employing OS and feature detection, and even compensating for some implementation vagaries. Constructs like this can be found in various other places in our code base, and while this is definitely not desirable, it at least saves the user from going through this hell, and this way, we support the full range of PHP 5.2.10 through 5.3.8 (inofficially 5.2.0 - 5.5.0-dev also works) on a variety of Windows and Un*x systems.

Following this strategy, we go as far as rewriting functionality previously available through a PHP extension to userland implementations: The FTP API (because of limitations in streaming support), the parse_url() function rewrite to work around behaviour changes, userland ini file parsing to support Unicode, a reimplemented MD5-crypt to compensate for a critical bug in crypt() in PHP 5.3.7 and our own MySQL protocol implementation to be able to support old MySQL 4.x instances, to name only a few cases.

The TDS protocol implementation supporting connectivity with Microsoft SQL Server and Sybase database servers is the most recent addition to this stack. Though not yet completely finished, we expect to be able to add it to one of the upcoming 5.8 releases.

apt-get meets the XP-Framework

2010-12-16T16:39:00+01:00

The XP Framework has an easy-to-use installation mechanism - simply downloading a setup script and piping it directly to PHP. What this mechanism cannot do though is to install PHP as a dependency itself, which is usually done in an operating-system dependant manner. On Debian and Ubuntu distributions, the packaging mechanism is called APT (Advanced Packaging Tool), which installs Debian packages (.deb files). In order to build such a package, we need to create a control file as well as the intended directory structure and wrap all that up using the "dpkg" tool (there's a PHP arrays are so comfortably usable for just about everything - mixing types inside, dynamically resizing them, mapping keys to values, this to that, and - using references - even can be used to create graphs. In addition, the PHP core library comes with more than 70 functions for manipulating them. This is great for rapid prototyping, as is the void-pointer in C.

The downsides of this approach is interop with most other programming languages, where arrays and maps are something conceptually different (Perl even has separate syntax for them, @ and %, and a mind-blowing implementation of the latter). For example, to know whether we're passing an int[] or a map of strings to object instances is going to make a big difference if we're, for instance, using EASC or SOAP to communicate with, say, Java or C#.

Show me the code

2010-09-27T10:37:45+02:00

After reading and agreeing with Show me the code some time ago, I thought about how to integrate source code examples on the XP Framework website. While lots of blog postings here contain sourcecode, this is not prominent enough - so I set up a new site dedicated to this purpose: The XP Code galleries. Enjoy

SVN URLs

2010-09-22T08:26:34+02:00

The XP Framework's checkouts you have on your disk should be originating from svn.xp-framework.net, and not from any other host name. While this may currently still work as all the other domains in use like xp-framework.de still point to the same server, we might want to change this in the future. To check what exactly you're using, type the following:

  ~/devel/xp/trunk $ svn info . | grep ^URL
  URL: svn+ssh://$USER@xpsrv.net/home/svn/xp/trunk

Should this read any hostname except svn.xp-framework.net, you can change it as follows:

  ~/devel/xp/trunk $ svn switch --relocate \
    svn+ssh://$USER@xpsrv.net/home/svn/xp \
    svn+ssh://$USER@svn.xp-framework.net/home/svn/xp

Bind server sockets to any free port

2010-02-01T16:00:15+01:00

At the company I work for, we let the XP Framework's unittest run on various different machines, including Windows 2008 server and 32- as well as 64-bit Debian Linux boxes, with PHP versions ranging from 5.2.0 - 5.3.1 (lots of permutation, yes).

On some of the newer machines we have configured

Unified runners in the web

2009-08-11T17:30:00+02:00

The XP framework had offered developers the power of an easy class loading setup via the new XP runners that are delivered with every release since several releases now. These runners have proven themselves very useful in day-to-day business, so we're working on porting them to the web!

With the so-called web-runners these new cool and useful features will become available for you:

Easier classpath setup
Classpaths will be constructed from .pth files, in the same manner as xpcli does it.

No boilerplate "index.php"s any more
you won't need the same index.php over and over in every project again; even more: you don't need any entrypoint .php any more even for SOAP- or JSON-endpoints.

Multiple etc/ configuration directories
you can switch between multipe etc/, eg. one for the test server and one for production, by changing a single file

Overwrite arbitrary settings for special servers
you can overwrite settings, eg. debugging settings, based on where your application runs - eg. on the development machine, you can have debugging enabled, while on production it's disabled. You don't need to have different files for them - no more mistakenly committed debug settings.

This article shows you how you can make use of the web runners in a XP application. Read on for more information!

PHP-Arrays: Maps and lists

2009-04-05T12:30:39+02:00

In the PHP world, arrays are maps are lists:

  $a= array(1, 2, 3);                // #1: A list
  $b= array('key' => 'value', ...);  // #2: A map
  $c= array(1, 2, 'a' => 'b');       // #3: Mix of both

Now this is (almost) perfect as long as you stay inside the PHP world; the only thing you have to know is when to be able to use array functions operating on "associative arrays" (like asort) instead of "numeric arrays" (sort), which is usually achieved by a bit of discipline. This is where a slight problem even inside the PHP world (and that's why it's only almost perfect) starts showing: There is no easy way to keep the both apart.

KISS: Keep it simply surveilled

2007-05-24T12:43:07+02:00

In the enterprise world, not everything is a website - there are a lot more types of applications you have to deploy to actually have a running enterprise website / application.

Often one of these "hidden" applications are cron jobs which take care of cleaning out not completed order jobs, doing lengthy cache pre-calculations, perform data mining or many other things.

Crons - or in general - backend applications are therefore an important part of your whole application. Running regularily they do their duty.

Of course, such a critical task should be surveilled. Read on to see how you can do effective, but simple surveillance with the XP framework's tools in combination with the open source surveillance system Nagios:

Making use of PHP5 features

2007-01-29T23:01:41+01:00

Today at work we had a presentation called "PHP5 features", where Alex and me presented what we consider the most appealing new possibilities.

Here's a wrap-up:

Why to prefer scriptlets over "standard" web scripts

2006-10-24T13:57:44+02:00

If you've written web applications with the XP framework, you've probably made use of the scriptlet.xml.workflow API. It provides templating via XSL files and in general a very comfortable way of creating dynamic web pages. Feel tempted to use "standard" web scripting (see below for example) for simpler tasks like CSV export, dynamic image creation or RSS feeds?

Here's why you shouldn't...

Shipping an application with XP archives

2006-10-15T18:58:51+02:00

Ever since, distributing XP applications to the "end user" could be quite a pain: you would've to tell people to install subversion on their servers, show them how to check out a copy of the XP framework with all it's millions of directories, let them put all required directories into their include_path - mostly there's more than one directory which needs to be included.
Then, whenever they want to upgrade the application, they need to update their checkout, exposing them to the danger of conflicts or incompatibilities in the classes API each time.

Now, with the arrival of XP class archives (which actually already exist for quite some time), this is a lot easier! Read on to see how shipping XP applications could be like in the future.

Using packages in XP

2006-10-14T20:26:00+02:00

Since RFC #0074 the XP framework has the built-in power to load classes from an class archive.

Now, imagine you want to install an XP application like dialog, and you have downloaded an tar file containg the application from the project's homepage. What do you do with it?

Creating packages for XP

2006-10-14T20:05:00+02:00

Today RFC #0074 has been accepted and merged into the public XP repository.

RFC #0074 describes some changes that bring the ability to the framework, to load classes from an archive rather than directly from a directory in the classpath. That does not seem to be so special, but it brings you some very cool things in the day-to-day work with XP.

So, let's take a look on how to create a new archive (.xar was chosen as extension for the time being, though this could still be changed).

Instance creation expression in PHP4

2005-07-17T18:22:56+02:00

The instance creation expression lets you create anonymous classes using the following form:

new ClassOrInterfaceType (ArgumentListopt) { ClassBody }

Supplying a ClassBody is available in PHP5 when using our patch to it, but not in PHP4. This article shows a way to simulate it.