Jeroens blog

Just under a month after the 0.6.5 release of both mapping extensions, the next minor update, 0.6.6, is available for download. No spectacular new features, but several important bugfixes. Several issues with coordinate parsing have been fixed, you can now using geocoding when behind a proxy, and wikitext should finally(!) behave correctly in marker pop-ups. Some internal changes have also been made, mainly rounding off the many changes I made in the 0.6.x branch. I expect this release to be the most stable one to date, and have therefore changed the extensions status from ‘beta’ to ‘stable’ on the documentation pages.

A lot of improvements have been made to the documentation as well. Both the Maps examples and Semantic Maps examples are now comprehensive and complete. There now are finally examples of using query templates, of distance queries and of some nice compound queries. Some more work is needed though, a lot of which is explaining basic functionality and fixing minor issues all over the place. I’ll be taking care of the most important things, but I’d be great if people using the extensions could help me out improving the documentation

This release is probably the last one before 0.7, in which I expect to be focusing on new functionality. I’m looking for people that want to fund the development of new features, so please contact me if you are such a person

Downloads:

• Maps 0.6.6 zip archive
• Maps 0.6.6 7z archive
• Maps and Semantic Maps 0.6.6 zip archive
• Maps and Semantic Maps 0.6.6 7z archive

As Google Summer of Code (GSoC) 2010 has ended, I’m writing this blog post to outline what I’ve done during the coding period and what the results are. Thanks go to the Wikimedia Foundation and Google for providing the opportunity to do this project, Brion Vibber, who mentored me, and to all other people who helped me out, especially Yaron Koren who I bugged the most

What I did during GSoC

My initial proposal was to create an awesome extension management platform for MediaWiki that would allow for functionality similar to what you have in the WordPress admin panel. After doing some research I realized this would require significant effort in two areas: configuration and deployment. After looking at some already existing tools such as the Configure extension and the Deployment Framework of Ontoprise, I decided to completely drop the configuration part and concentrate on the deployment work.

I started with porting the filesystem abstraction classes from WordPress, which are needed for doing any upgrade or installation operations that include changes to the codebase. (The current MediaWiki installer can do upgrades, but only to the database.) I created a new extension called Deployment, where I put in this code, and which was intended as a place to experiment with all the MediaWiki-installation side deployment stuff. As You obviously want this functionality to be part of MediaWiki itself, I wrote it with the idea of moving over the code to MediaWiki core once it was finished. It turned out that doing filesystem upgrades securely is not an easy task though, so after finishing the port, I quitted work on this as I decided to do other functionality first.

I then poked somewhat at the new MediaWiki installer, which is a complete rewrite of the current installer with a lot of new cool stuff and a totally more awesome interface. I made some minor imrpovements there, and split the Installer class, which held core installer functionality, into a more generic Installer class and a CoreInstaller. This allows for creating an ExtensionInstaller that uses the same base code, such as database, filesystem and LocalsSttings manipulation.

After this I started thinking about how to best structure a package repository for MediaWiki and extensions to get updates and new extensions from. I had a look at PEAR and CPAN, as well as WordPress, although I don’t learn a lot about the later. Apparently their repository code is not freely available After discussion with Brion I decided to just create the repository from scratch, and started working on another extension, titled Distribution, for this purpose. I merged it together with a rewritten version of the MWReleases extension written by Chad, which already had core update detection functionality.

After the Distribution API’s where working decently I started work on the Special pages in Distribution that would serve as the equivalent of the WordPress admin panel. As I put of the configuration work, and also the file-system manipulation for the initial version, this came down to simply listing currently installed software, update detection and browsing through extensions available in the repository.

On top of my GSoC project itself, I did quite some other MediaWiki work in “my free time”. I released 5 new versions of Maps and Semantic Maps, starting with 0.6 and ending at 0.6.5. As I finally got core commit access, I also poked at some other things, such as Special:Version, which now will automatically put all extensions of unknown type in the “other” category, and will display this category as the last one. Plus misc minor improvements to a verity of extensions. This all amounts into a little over 550 commits to the MediaWiki SVN repository during the GSoC coding period.

State of the code

The Distribution extension has the infrastructure for storing and providing extension and core data via the MediaWiki API basically ready for use. It adds 4 database tables to MediaWiki:

• distribution_units: This table stores non-version specific info of ‘release units’ . Currently these unit’s are extensions only – the reason I went for a more general name is to allow for adding other things such as skins and content packages later on. The info here consist of a name, a URL, a description and a pointer to the “current version”.
• distribution_unit_versions: Entries in this table contain info about a specific version of a ‘release unit’. The info here consists of a version number, release status (beta, rc, stable, deprecated, …), release data, authors, description and some installation data.
• distribution_mwreleases: This table contains MediaWiki releases. It has been merged in from MWReleases, so all credit for it goes to Chad.
• distribution_packages: This table is not in use yet, and needs some more work. The goal is to be able to install a “package” onto your wiki which can contain multiple ‘distribution units’. This would basically be the same as Semantic Bundle is doing now, but a lot easier to set up and maintain.

The API modules added are:

• ApiQueryExtensions: Returns a list of extensions matching certain search criteria, which can include keywords, tags and authors. Only extensions with a version that has a release state acceptable for your installation are returned.
• ApiMWReleases: Gets the current MediaWiki releases. Like this distribution_mwreleases database table, this has been merged in from MWReleases and all credits go to Chad.
• ApiUpdates: This API module returns update information for the extensions you give it, and does the same for MediaWiki itself if a core version number is provided. The only info that’s returned is a version number for each unit or core, if there is an update. Otherwise nothing will be returned for that unit or core.

To populate the database with existing extension info I wrote a maintenance script “getSvnMetadata”, which goes through a local checkout of the MediaWiki extensions directory and get’s the names from the extensions. I haven’t found a good way yet to also get other extension data though.

The Deployment extension contains an abstraction layer for repository interaction and several interfaces that use this. The abstraction layer allows for supporting different kinds of repositories. The only implementation it currently has is for interaction with repositories provided by the Distribution extension.  It’s also a convenient point to implement caching, as you probably don’t want to send the requests for available updates every time you view a page on the admin panel, and allows for changes to the format the repository uses without any effects in other parts of Deployment. The interfaces that are finished to some extend are:

• Special:Extensions: This page lists all installed extensions and allows you to filter on extension type. It’s based on the WordPress “plugins” page and is currently only an improved version of the extension list in Special:Version. It’s the only special page added by Deployment that can be viewed by non administrators. When logged in however, every extension has a list of links allowing you do various actions. The extension info is handled by a new class ExtensionInfo, which parses the info of individual extensions in $wgExtensionCredits, and provides a more convenient way to work with it. This allows for adding support for a new, better, extension info format later on. A planned feature for this special page is showing update notifications in each extension row.

• Special:Install: This page allows you to search through available extensions in the repository. The interface is based on the “plugin-install” page of WordPress and allows for searching extensions based on term, tag or author. After performing a search you get a list of matching extensions showing their name, version, authors, description, link to the documentation, and a link to download them. Later on this download link will be replaced by an “Install” one.

• Special:Update: This page will inform you of any updates to both core and extensions. It’s behaves basically identical the WordPress “update” page.

The extension allows you to configure several aspects of the repository interaction:

• $wgRepositoryApiLocation: This might be an obvious one, but also a very important one, as it allows you to use a repository other the the Wikimedia Foundation one on mediawiki.org, which will be the default.
• $wgRepositoryLocation: This is similar to the previous setting, but links to a web interface providing browsing capabilities through the repository, or at least some additional info.
• $wgRepositoryPackageStates: This is a list of allow release states. By default these will only be “stable” and “beta”. Early adopters can also add “dev” and “alpha”, and there also is “rc” and “deprecated”.

What’s next?

Although some very basic functionality is working, quite some work still needs to be done to get this to the WordPress-awesomeness level. Let’s first have a look at Distribution and then Deployment:

The most basic issue with Distribution currently is that there is no script yet that allows collecting all current extension data, which is needed for it to be of any use. I’m not sure how gathering current data can be properly automated, which is the main reason the script doesn’t exist yet. Any suggestions here are very welcome! After the initial version it should be possible for extension authors to edit their extensions data, and create new releases. For this we’ll need some new special pages. The data itself can then be used to populate the extension pages on mediawiki.org, and some new magic words such as “current MediaWiki version”, can automate a bunch of stuff. After these things new features can be added, such as the management of packages, and more detailed extension information, including things such as dependencies and compatibility info.

Deployment mainly needs interface work, and will need additions to support any new information provided by the Distirbution repository. A cool feature that could be added is supplying the repository with installation information (obviously optionally), which would allow the developers to get an idea of which versions of MediaWiki core and extensions people are using. After the whole MediaWiki deployment model has been revised and is up and running, it’s configuration can similarly be reinvented. The interfaces added by Deployment can then be adapted to allow contain extension configuration.

GSoC 2011?

This was my last GSoC as a student, as I no longer qualify, since I quitted my official studies. If I’m still doing MediaWiki development next year, which I guess is pretty likely, there is a lot of change I’ll be signing up as a mentor though If you are interested in being a student in 2011, you can already put your name on the 2011 GSoC page

Some useful links

• My blog posts about this project
• The Wikimedia 2010 GSoC page with all GSoC projects
• Distribution and Deployment extensions
• My MediaWiki.org user page

Just a few quick screenshots of Special:Extensions, on which I’ve been working today. The first screenshot shows Special:Extensions page displaying a list of all the extensions I have installed on my local wiki:

As you can see, you can now filter on extension type with the control right below the “Installed extensions” title. Here I have filtered on the SEMANTIC extensions:

An interesting change I made is that you can now access this page without having the siteadmin permission. Doing this will get the above, but without the add new button and administration controls (currently only “Deactivate” which is there only for show so far). This way this page will be a nice addition to Special:Version.

Tomorrow is the last coding day in Google Summer of Code 2010, during which I’m planning to focus on the update detection functionality, or rather creating the interface for it, as the plumbing for it is all but done. I also want to move several classes from Deployment over to MediaWiki core, as they make more sense to have there, and would allow for some nice improvements.

Since my last blog post about my GSoC project, which aims to bring more awesome deployment capabilities to MediaWiki, I’ve been putting my time into both the Distribution and Deployment extensions. I was pleased to find a bunch of stuff was easier to do then I had imagined, and now I finally have some functionality you can actually see working – yay It’s not a lot, as this is just very rudimentary and even uses demo data at places. Still it’s very nice to be able to post some screenshots after months of doing research and poking at code. I also got a new crappy diagram (although I think I’m succeeding in getting them less crappy each iteration) that shows the architecture of the initial versions I’m working towards.

The following screenshots show an import script running. This script is part of Distribution and is meant to get data from a checked out copy of the extensions directory and store it into the database tables provided by Distribution. I haven’t found a good way to actually get the extension data other then their path names (for example ‘SemanticMediaWiki’), so have a function that’s just returning some demo data.

Via Deployment you can search for extensions by keyword, author or tag. This is done by making a request to the API provided by Distribution which serves the data collected by the script. This screenshot shows the interface I have created so far:

And after clicking the button, you get:

As I’m doing with all special pages in Deployment, Special:Install’s layout and functionality is based on what WordPress has in it’s admin panel.

I also put some work in Special:Extensions already, although it’s basically just Special:Version with just the extensions for now.

I’m not wring a real comprehensive overview of what features there are already, which are planned, and how I plan to create them for now, as there is little time left in GSoC (only 3 days!), and I want to get some more work finished before then

With only 2 days till the suggested Google Summer of Code ‘pencils down’ date, and a week longer until the firm one, I’m using my remaining time to get some basic functionality working for my GSoC project. I’ve started creating a new extension called Distribution that will provide an API module which can be used to query extension meta-data. Later on it should also be able to do this for core, and provide archived packages that can be downloaded to your MediaWiki server, and directly installed. Initially I’ll probably simply be pointing to the ExtensionDistributor extension on MediaWiki.org, which can create archives for extensions on request. The Deployment extension which I started on earlier on will use data obtained via the API Distribution provides to display available extensions on your local installation.  Right now I’m attempting to get the ExtensionDistributor working locally, so I can develop the Distribution extension alongside it, and confirm everything works. This will take some time as it uses Linux/UNIX specific commands, forcing me to use my Kubuntu install, on which my dev environment is only partially set up at the moment.

Maps and Semantic Maps 0.6.5 are now available for download. This release contains mainly internal changes to improve code modularity and fix some security concerns. Several bugs have been fixed as well, and a new hook has been added to Semantic Maps. This hook will get you the map format as default one for queries where you only ask for coordinates when using SMW 1.5.2 or above. For a full list of changes since 0.6.4 see changes to Maps and changes to SM. Everyone running 0.6.2 or older is advised to upgrade as soon as possible. 

This release is notable for it being the first one in which I’m happy with the code-base as a whole. It took me a year to get here, but now I think the way the mapping extensions work is good and solid. This means you can now extend Maps and not be afraid the code will be incompatible in a few weeks due to changes. This also means that I’ll be focusing more on actual functionality rather then refactoring in future releases. I’ll be progressively building a little guide that explains how the extensions work from a developers perspective and how to extend them.

I might release another minor update in the 0.6.x series if any significant issues are found in 0.6.5. Further plans are finishing up a bunch of changes I’ve started to make in Validator, which I’ll probably release as 0.4 then, and to start working on Maps and Semantic Maps 0.7, which would aim at adding new features and improving existing ones. A likely new feature I’m particularly looking forward to implementing is several tag extensions that do the equivalent of the current parser functions added by Maps. The timetable for all this depends a lot on which other things I get cough up in (I’ll probably continue putting effort into the deployment stuff for my GSoC project) and what kind of funding will be available.

Downloads:

• Maps 0.6.5 [zip - 7z]
• Maps and Semantic Maps 0.6.5 [zip - 7z]

You can also view the release announcement at the documentation wiki.

I got a new diagram!!!1!11!! It’s based on my previous one, but slightly more elaborate, and a lot less messy, as I now used Dia to create it

Legend:

• Striped lines: Existing components where code will be copied from, or based upon.
• Full lines: Components of the complete deployment model.
• Thick full lines: Core components (of the deployment model) that I definitely want to have completed during GSoC.

Since my previous post about my Google Summer of Code project I have been poking at the new MediaWiki installer to see what’s there already, how it is there, and how I can integrate it with the above deployment model. I’ve made a bunch of style and documentation improvements while going over the code, and renamed some things to make more sense. And I had Tim Starling clean up a bad svn commit I made

So what I’m doing now is splitting the current ‘Installer’ class, which is part of the new installer, into 2: Installer and CoreInstaller. Installer will hold general installer functionality and be part of the whole deployment model, while CoreInstaller will hold installer functionality specific to core, and will be part of the new installer. After that I can create an initial version of CoreInstallers counterpart: ExtensionInstaller.

Today my MediaWiki.org user page is one year old – I created the first version on July 20, 2009. With my SVN account also approaching it’s first birthday, I can now say I’m doing MediaWiki development for a year. A lot has happened in this year.

I created the Maps and Semantic Maps extensions, and have continues releasing big and small updates the whole year long. At the end of 2009 I created the Validator extension to facilitate parameter handling in Maps and Semantic Maps. In early 2010 I was contracted by the Wikimedia Foundation to create the Storyboard extension, and by the Karlsruhe Institute of Technology to do work on Semantic MediaWiki. In May 2010 I started working on my Google Summer of Code 2010 project to create an extension management platform for MediaWiki. In between all these things I made various contributions to other extensions, including Semantic Forms, Semantic Internal Objects, Page Object Model, Semantic Compound Queries, Semantic Result Formats and Approved Revisions.

Next to all the code I created and released, I also attended several events and gave a number of presentations. These events include SMWCamp 2009 in Karlsruhe, the Berlin developers workshop in April and Wikimania 2010 in Gdansk.

I’m currently all time MediaWiki comitter #18, with 1080 commits. Looking forward to all the awesome stuff I can do in the coming year

I figured having some unit tests for Maps, the MediaWiki extension to work with geographical data and display it by embedding dynamic maps into your articles, would be beneficial to it’s quality. It’s pretty hard to try cover all possible use cases with manual tests, and consumes a lot of time in any case. I therefore decided to try create some tests for the coordinate parser and formatter class, as it’s arguably the core feature of Maps.

I started off by trying to install plain PHPUnit, which is the most commonly used unit testing framework for PHP. This took me a while, as you are supposed to install it using PEAR (PHP Extension and Application Repository), a repository tool for PHP applications, and has never used this before. After two hours or so of messing around, I got both installed Then I went on investigating how I could best integrate this into my work-flow, and discovered that PHPUnit comes bundled with Zend Studio, seamlessly integrated, working completely out of the box o_O.

I then wrote a test case for the coordinate parsing and formatting class of Maps. I had a hard time getting it to work, as I needed to include MW itself, as the class uses MW functions. After some non-constructive discussion with several fellow MW devs I found a way to get it to work by including the maintenance script entry point, and tricking MW into thinking the call was made from a CLI. I now have a test case for the coordinate class, with tests for most of it’s functionality. Some more test data, and maybe some extra tests would be nice. A tricky thing in the case of this class is founding errors, which are hard to take into account, especially if you only want to allow them to a certain degree.

This particular test case is already paying off, as it made me find 3 subtle errors in coordinate parsing or formatting, that did not show up in my manual tests, as I was not covering the test data causing the issues.

I’m now planning to maybe write test cases for the distance parser to, which should be rather easy to do. I probably won’t create any others for Maps, as it’s rather time consuming, and I have a lot of other things to do right now. When I create new classes that are suited for unit tests in the future, I’ll definitely write tests for them as I build them up though, as it’ll not cost a lot more time then doing manual tests, and will ensure the classes are really solid.

About a year back I decided I had to change my development environment from working on a remote server with a simple text editor to something more solid, if I wanted to do serious PHP development.

I went for Eclipse as IDE, which is without a doubt the most awesome IDE out there, as it’s completely open source, robust, and has a lot of extensions that make it usable for an awful lot of languages. For PHP there is the open source PHP Development Tools Project, and the commercial Eclipse based IDE build on top of this, Zend Studio. At that point having my development environment as mobile as possible was rather important, as I often occupied machines other then my laptop or my own desktop. Therefore I put both Eclipse and my server on an usb.

Now, a year later, a lot has changed, and I finally updated my tools accordingly. First of all, I’m now also using Linux, and plan to leave Windows into the dust bin soon, so prefer tools that work on both operating systems. Secondly, I now only develop on my laptop and own desktop machine, so portability is not as important any more. Also, I’m now doing a lot more serious PHP development as I was doing a year ago, and would benefit a lot from more decent debugging, testing and profiling tools.

What I did was throwing out my mobile web server and install Zend Studio, together with Zend Server Community Edition (which is free). They integrate in such a way that you can do code tracing, work with breakpoints, profile code, ect, all out of the box. If you are developing PHP applications like me and in search for a good tool, I can definitely recommend this. Zend Studio isn’t free, but it’s worth the price. Not going into a complete list of awesome stuff PDT and Zend Studio include, but this blog post, although a little dates, does a good job at it.

It’ll take me a while to integrate these features into my work-flow, as I’m not used to having them available, but I expect this to start paying off rather soon then late Also waiting on a new release of Zend Studio build on Eclipse 3.6 (Helios).

(O yeah, can’t write a post about Eclipse without saying: NetBeans fails )