Personal Blogs

This post is about the journey that I followed trying to understand Moodle Themes.  Moodle Themes are pieces of programming magic that change the visual appearance of your Moodle installation.

If you download Moodle and play around with it, you might eventually arrive at a decision that it might be useful within your institution.  You might hold a meeting with senior management where you may say, 'I think it's a good idea if we try to use this thing call Moodle to host some of our courses'.  After answering some difficult questions about maintenance and development costs, your managers might say, 'okay, you've convinced us... let's give it a go, I'll give you a budget'

Other than figuring out which operating system and database to use and where (and how) your instance of Moodle is to be hosted, one of the first development activities you will have to do is make sure that your Moodle system is 'on brand', i.e. it's visual appearance should reflect the institution that you work for.

This is pretty much what I have to do.  I have to try and make my 'vanilla' (unmodified) version of Moodle blend in with a set of existing web pages that have been built as a part of a research project I'm working on.  Other development teams within my university have already done something similar with their production version of Moodle, but I need to tackle this problem myself.

I start with a couple of questions: what makes up a theme and how might you go about changing one or maybe even making a new one?

Resources galore

Before I can answer these questions I needed to find something to read, and it didn't take a lot of browsing to find a number of potentially useful resources.

The first page that I discovered was a link to over one hundred different themes thanks to the Database of Moodle Themes.  Perhaps I shouldn't be so surprised given the number of Moodle installations that are out there in the world.

I soon discovered the Themes documentation pages and a number of other related links, including a set of themes related FAQs and dedicated discussion forum.

The Themes documentation link (for a Themes novice) seems to be the most useful.  One of the sections says that themes can be delivered in zip files.  You download them, unzip them and place the contents in the /moodle/theme directory, and then click on some admin tools to activate it.  This sounds almost too easy!

Towards Code

Being someone who likes to view code I thought it might be useful to look at some of the magic that makes Moodle themes work.  To do this, I chose a random theme from the themes database and unzipped a folder to my desktop.  To begin to make sense of it properly, I felt that it might be a good idea to compare this random theme against one that already existed.  This made me answer, 'which theme is used by default?'

To answer this question, I logged onto my local instance of Moodle (which was running on my local machine, localhost) as an administrator.  After struggling to remember my username and password, I clicked on the Administration link, followed Appearance, Themes and then on the Theme Selector link (because I couldn't really make sense of the Theme Settings options).

I quite like the Theme Selector page.  It presents all the different themes that have been installed.  The current theme that is selected is highlighted by a black square.  The one that was selected by default (in the case of my installation - I cannot remember whether I changed it) was named standardwhite.

I delve into the Moodle code area, take a copy of standardwhite and placed it alongside the one I have randomly downloaded and started poking around.

Looking at code

I noticed similarities and differences.  The similarities are that some of the filenames are the same.  I see two PHP files, styles and config, followed by two html files, header and footer.  There seems to be a CSS file (Wikipedia) in both themes (but the downloaded theme contains a few more than the default theme).  I also notice a graphics file called gradient in the default theme (which is a jpg), and a png graphics file in the other one.  A big difference lies was that the theme I have downloaded contains a directory which seems to contain a bunch of graphic files.

Before deciding I'm terribly confused, I decide to do one more thing: open up both of the PHP files to see what they contain.

In a config script, I see assignments to a variable called $THEME.  Different attributes appear to do different kinds of magic.  Looking in the styles script, a comment tells me that 'there should be no need to modify this file'.  It seems to do something that relates to the presentation of a CSS file.  That is good enough for me!

I have a quick peek into the header and the footer html files.  It looks like these are templates (of some kind) that are filled out using the contents of some PHP variables.  Obviously the pages that the Moodle code creates have a pretty well defined structure, and presumably this structure is documented somewhere.  This is perhaps something I might need to remember later.

Return to the documentation

At this point, I roughly (think) I know what a Theme comprises: some magic scripts which define some variables (and some other stuff), some header and footer scripts which look at bit like templates, a CSS file of some kind, perhaps a graphic (which could be used by the CSS file?) and maybe a bunch of graphics that replace those that are used in Moodle by default.

If this is my current understanding, can I now find the documentation easier to understand?

I soon uncover two further pages: Make your own Theme and Creating a Custom Theme (the first link seems to be easier to understand).  A couple of clicks takes me to a documentation page called Theme config file which goes some way to explaining the variables that I have touched upon above.

The final comment in the Creating a Custom Theme page was instructive.  Other than saying that you can't change everything, if you want to make your site look like an existing site, it might be a good idea to make use of a tool called Firebug which is a plug in for your Firefox browser.

With Firebug, you can browse to a web page of your choice and uncover what CSS definitions have been used to build its visual appearance.  I've used Firebug before, and mentioning that it is a good tool is certainly a good piece of advice.  The Moodle developers have also been kind enough to prepare a CSS FAQ which is certainly worth a look.

Although I could have tried to create a new theme from scratch, I'm in a lucky position since one of my colleagues has already created a customised theme for a custom instance of Moodle.

Towards testing things out

To test things out, I copy of my customised theme into my local 'themes' directory and hit refresh on my browser.  I then select my newly installed theme and everything starts to go wrong.  The action of selecting a theme seemed to have rendered my local copy of Moodle useless since only a tiny fraction of a HTML page is created (which I see by viewing the code the browser receives).

A problem seems to have been created since the version of Moodle that I am using and the structure of the theme that I have transferred are not completely compatible with each other.  I need to go back to my default theme! But how do I do this? Where are the theme settings held?

My first guess is in the database.  I open up a front end to the MySQL database that is running on my PC, using a tool called SqlYog.  I eyeball the contents of the database to see if there's anything I can use.  I discover a 'config' table, but this doesn't tell me much.  I did, however, discover that there is a theme setting within individual courses as well as individual users.

I turn my attention towards the code by first looking at the code within the themes directory and I soon find myself fruitlessly searching through different libraries.  Finding a simple answer may necessitate spending quite a bit of time.

To get things working again, you sometimes have to cheat.  I renamed my theme to something totally different and refreshed my Moodle page.  Moodle then had no choice but to return to its default setting (which was, again, 'standardwhite').

Incrementally merging

I have two themes: one theme that I want to use but doesn't work (because it has been modified for a customised version of Moodle), and another theme that does work which I don't want to use.  When I'm faced with this situation, I try to get 'code to speak to me' by incrementally taking the one that works and making it look like the one that doesn't work.  I find I can really understand stuff when things stop working!

I begin by looking at the files and then the contents of the files.  The first thing that strikes me is that the header and footer files are quite different.  There seems to be quite a bit more happening in the customised theme when compared to the standard theme.  A step at a time I move files across and test, beginning with the favicon, then the config file, and finally the pix's.  I discover that both themes require the use of a CSS file that is contained within the standard theme directory.

The effect of moving files around seems to produce, more or less, what I was after.  The interactive 'side blocks' (particularly the show/hide buttons) are not presented as they should, but further searching reveals a magic variable, allowuserblockhiding that can be used to control this functionality.

Moodle version 2

A question to complete this post is: what is the situation regarding Moodle version 2.0?  This is a development that I have heard about for some time, but I have not heard recent any announcements regaring its expected release.  After a quick search, I reacquaint myself with something called the Moodle Roadmap.

This appears to state that there will be a beta release of V2 by the end of 2009, followed by some months of testing before a final release.  Judging by the planning document, there appears to be quite a lot more coding to do (nearly four hundred days of development time to go, so we should expect some delays).

I appreciate that giving opinion is certainly a lot easier than giving code, so I hope that Moodlers who read this section will forgive me.  I personally hope that the code for the next version is a lot cleaner.  Since the developers are forced to move to PHP version 5, I hope they will choose to adopt its object-oriented features which can help developers to form clearer (less leaky) abstractions.

In a perfect world, developers should be able to look at a screenful of code and be able to describe, more or less, what that section of code does without having to look at other code (providing, of course, they more or less have an understanding of what the product does).  From what I have seen so far in version 1.9, there is a long way to go to, but I'm certainly looking forward to learning how things have moved on in version 2.0.

Wrap-up

It's great that the developers of Moodle have designed it in such a way that it is 'themeable' (if there is such a word).  In some respects, I was surprised to discover things were not as difficult as I had expected.  Whilst, in some ways, going directly to the code and looking what is there may be a daunting challenge, it is one that I certainly recommend doing.

There's a whole lot more to the issue of Moodle themes.  I haven't touched upon the structure of Moodle pages and how they relate to elements in stylesheets, for example.  I'll leave this challenge for another day!

This blog post represents a review of the second International Education for All conference that I was lucky enough to attend in September 09.  I originally intended to post a review earlier, but mitigating circumstances (which I hope will become clear at the end) prevented this.

Like the first conference, held in '07, this conference was also hosted at the University of Warsaw.  The '07 conference represented a finale of an EU project, a collaboration between universities and other organisations from Germany, Poland, Estonia, Croatia and others (please forgive my poor memory!), but this one was slightly different.

Below I attempt to present a brief summary of some of the sessions that I attended.  There were three parallel sessions, so I had to choose carefully.  This is then followed by what I took away in terms of the themes of the conference.

Opening Keynote

The opening keynote was by Dianne Ryndak from the University of Florida.  Dianne explored the topic of inclusion, particularly the differences between generalised and specialised education.  Dianne explained how personalised support and learning activities could be provided as a part of general learning activities.

She went on to present a powerful description of two students: one who was educated within a segregated school, the other who was educated, with the provision of additional support, through a main stream (or general education) school.  I remember her saying that 'education is a service that goes to the student, not a place where the student goes' and that education should be 'only as special as necessary'.

Although Dianne's presentation primarily related to high school education the themes she highlighted can be directly brought to bear on higher education too.  Technology can be used as a way to help with the inclusion of people with disabilities main stream education.  This said, teachers have a more important role where they need to be viewed as collaborators as well as educators.

Three dimensional solid science models for tactile teaching materials

I sometimes like to visit museums.  One of the things that frustrate me is the sight of signs that say 'please do not touch!'  This strikes me as particularly unfair when I discover sculptures in art galleries.  Given that sculptors use their haptic sense when creating an object, it seems unfair to deny visitors the possibility of using this same modality.

Yoshinori Teshima, from the Digital Manufacturing Research Centre in Japan, gave an inspiring presentation where he showed a number of different models, ranging from abstract objects (such as polyhedra) through to hugely magnified representations of microscopic creatures that can only be seen under a microscope (imagine a microscoping monster the size of your fist!)

Yoshinori briefly spoke about the manufacturing methods, which included stereolithography and 3D printing using either plaster on nylon powder.  His relief emphasised models of the earth and mars were fabulous.

It struck me that his models could be used by all students, regardless of visual abilities.  It also struck me that the ultimate use of such models within the classroom depends ultimately upon the skills and the expertise of the teacher.

Talking Tactile Tablet

I have heard about tactile tablets before.  This presentation demonstrated a product that was also included within the assistive technology exhibition that was also hosted at the conference.

I came away with two points from this presentation.  Firstly, referring to three dimensional objects using two dimensional symbols is a skill that I take for granted.  Secondly, it is now possible for educators to author their own tactile materials.  We were shown how it was possible to create a small family tree.  Audio materials were recorded using Audacity (Wikipedia), which were then associated to positions on a tablet.  Corresponding tactile representations could be produced using embossers.

Opening Linux for the Visually Impaired

This presentation primarily focused upon a screen reader called Sue (Screenreader Usability Extensions) that was developed by the Study Centre for the Visually Impaired Students (SZS) based at the University of Karlsruhe, Germany.  This presentation reminded me a little of a presentation of the Orca screen reader, made at the Aegis project dissemination event that I wrote about a couple of months ago.

One of the interesting things about Sue was that it could be connected to both a refreshable braille display (Wikipedia) (visiting this page was interesting, since it mentioned a new type of refreshable display called a rotating-wheel display) and a screen magnifier at the same time.

Although Sue could be considered to be 'yet another screen reader', having multiple versions of similar products is undeniably, in my view, a good thing.  Competition between individual products, whether it is in terms of popularity or functionality can help their development and enhancement.

Distance Education and Training Programme on Accessible Web Design

I was drawn to this presentation due to involvement in the Open University Accessible online Learning and Fundamentals of Interaction Design courses.  I was not to be disappointed.  There were some strong echoes with these current courses, but I should say the curriculum is perhaps complementary.

The course was developed as a part of a European project called Accweb with the intention of creating distance learning materials that could address a need for a professional qualification or a certificate in accessible web design. The materials comprised of eighteen units which could be delivered through the ATutor VLE, amounting to the equivalent of 60 points of study.

Key elements of the curriculum included:

• Fundamentals of web accessibility
• Guidelines and legal requirements
• Assistive technologies
• Accessible content creation (which included issue such as methodology, evaluation, rich internet application and authoring tools)
• Design and usability (themes from human-computer interaction)
• Project development

The materials do not seem to be available through this site at the moment, but I hope they will be available in time.

Helping children to play using robots: IROMEC project experience

This presentation, by Francesca Caprino, outlined the IROMEC project, which is an abbreviation of Interactive Robotic Social Mediators as Companions and a sister project called the adapted robot project.  Francesca began by describing play: what it is, what it can do and considered the effect of play deprivation on the development of children.  Robots, it was argued, can help children with physical disabilities and other impairments participate in play activities.

The robots that were described were essentially toy robots that were modified to allow them to be controlled in different ways.  Future research objectives included uncovering of new play scenarios, considering how to adapt or modify other robots and assessing the educative and therapeutic outcomes of robot assisted  play interventions and developing associated guidelines.

Studying Sciences as a Blind Person: Challenges to AT/IT

Joachim Klaus introduced us to the Centre for the Visually Impaired Students, which seemed to have similarities to the Open University Office for Students with Disabilities (more information is available through the services for disabled students portal).

After presenting an overview of the centre, Joachim presented the ICC: International Camp on Computers and Communication.  The ICC 'tries to make young blind and visually impaired students aware what technology can do for them, which computer skills they have to have, where they should put efforts to enhance their technical skills, the level of mobility as well as their social skills'.  Using and learning to use assistive technologies can be difficult.  This international camp, which is held in different countries, can help people become more skilled at using assistive technologies, thus removing substantial barriers to access.

Improving the accessibility of virtual learning environments using the EU4ALL framework

During the conference, I gave a short talk about the EU4ALL project I am working on.  The presentation focussed on an architecture that the project has been creating and how it can improve the accessibility of services that are delivered to students.  The architecture takes into consideration a number of different stakeholders, each of which has a responsibility in helping to deliver accessibility.  My slides are available on-line through the Open University Knowledge Network (presentation information).

At the same time as my presentation, my colleague Elisabeth Unterfrauner from the Centre for Social Innovation, Technology and Knowledge, Vienna, was presenting her research, the socio-economic situation of students with disabilities, also carried out within the EU4ALL project.

Fostering accessibility through Design4All education in mainstream education

Continuing the theme of EU projects, Andrea Petz gave an interesting presentation about universal design, or Design4All.  Andrea has been involved with EDeAN, and abbreviation for the European Design for All e-Accessibility Network.  EDeAN has studied how D4ALL is covered or treated in different universities across Europe and has helped to guide the development of a masters programme.

Andrea began her presentation by saying that D4ALL is not design for the average, but for the widest possible group of users and went on to talk about the principles of universal design (Wikipedia):

1. Equitable use
2. Flexibility in use
3. Accessible information
4. Tolerance for errors
5. Simple and intuitive
6. Low physical effort
7. Size and space for approach and use

Andrea pointed us towards a conference called the International Conference on Computers Helping People with Special Needs (IICHP).

Inclusive science strategies

Greg Stefanich added two more to Andrea's list of principles, namely:

1. Build a community of learners
2. Create a positive instructional climate, i.e. one that is welcoming.

Greg also connected his talk to the theme of inclusive education by saying 'a person in a regular class room setting will have better relationships with the general public, family and be employed' and emphasised the view that inclusion of all students will have no real consequence on other students.  An important point is to spend time to get to know the needs of individuals so they can be effectively supported.

Foreign language courses for students with hearing impairments

Ewa Domagała-Zyśk talked about her experience of teaching English to hearing impaired students.  Her presentation made me reflect on my own experience of using the virtual world SecondLife (although Ewa's presentation was mostly about why teaching foreign languages is a good thing and what some of the challenges might be).

Quite some time ago, I was adventurous enough to visit a couple of 'Polish speaking' virtual bars where I tried to interact, using text, with some of the 'regulars' and found myself totally lost.  This experience showed me that this was an interesting and predominately unthreatening way to help to learn (and understand) written language. It did make me wonder whether virtual worlds (in combination with real-word assistance, of course), might be an interesting way to expose people to new languages.  The issue of whether such environments promote the creation of new dialects is, of course, a whole other issue.

Educational practices towards increasing awareness among academic teachers

Dagmara Nowak-Adamczyk (or one of her colleagues) spoke about the DARE project, a disability awareness project.  The project website states, 'The long-term objective of the project and the DARE Consortium is raising public awareness of disability and the way people with disabilities function in modern (knowledge-based) society'.  The project has produced some training materials which are currently being evaluated.

Access for science students with disabilities in an open distance learning institution in South Africa

I was particularly looking forward to this presentation since its title contained particularly interesting themes.  Eleanore Johannes, from the University of South Africa, spoke about different models of disability, introduced us to the Advocacy and Resource Centre for Students with Disabilities (ARCSWiD) office and spoke of some of the challenges that students face: funding, electricity, inaccessibility web pages and training.  She also described a qualitative research project that is exploring the experiences of science students with disabilities that is taking place over a period of three years.

No contradiction : Design4All and assistive technologies

Michaela Freudenfeld introduced the INCOBS web portal that provides information about assistive technologies that are available in Germany.  The INCOBS portal has the objective of carrying out market surveys of products and services, testing of assistive devices and workplace technologies, evaluating the accessibility of software applications and offer seminars for facilitators and advisors.

Understanding educational needs of students with psychiatric disabilities

Enid Weiner, from the Counselling and Disability Services, York University, Canada, gave an impressive hour long talk on the theme of mental health difficulties.  The subtitle of her presentation was 'making the invisible more visible'.

Enid spoke about a number of interesting related themes, such as different illnesses, the effect of medication and that some illnesses can have an episodic nature, which may cause the place of learning to be slower or take place over an extended period.  Accommodations are to be made on a case by case basis.

Enid emphasised the importance of a 'community of support' and said how important it is for educational providers not to 'get hung up' on an individual diagnosis and instead focus on individual accommodations i.e. what learners need to study.

Environmental influences on participation with disabilities: a Sri Lankan perspective

This was an interesting presentation since it presented a different perspective.  Samanmali Kularatne outlined the situation in Sri Lanka and then described a study that is aiming to explore the experiences of children with disabilities in mainstream schools.

The study adopts a qualitative approach.  Interviews are carried out in class rooms, which are then transcribed and subjected to thematic analysis.  The participants include children, teachers, parents and non-participative observers.  Themes identified included: attitudes, values and beliefs, support and relationships, products and technology, natural and built environment.

The conclusion was that inclusion is not really a reality and that there is a lack of resources.  The actions resulting from the study includes further communication with educational authorities, an awareness programme for parents and launching a project to try to initiate more inclusion.

How AT can help with learning maths for people who are print disabled

The presentation and manipulation of mathematical notation is a perennial problem.  When some mathematical expressions are translated into spoken language ambiguities can easily arise.  One proposed solution is to make use of the LaTeX (Wikipedia) language.

The challenge is not just technical.  Acceptance of technology relates to the willingness of learners to accept technological solutions and effectiveness of teachers to communicate their potential benefits.  It also relies upon educators having both the time and wiliness to understand different tools.

Considering different definitions of disability

Paweł Wdówik from the University of Warsaw Office for Persons with Disabilities spoke about the different definitions of disability and the differences that exist between primary and secondary education.  Paweł highlighted that through the medical model, if you don't have a medical model, then a disability is not likely to exist.  As a result, people who do have disabilities are likely to slip through the system.  Paweł emphasised that the views of the individual should always be fundamental.

Working towards inclusive education in Europe

Andrea Watkings from the European Agency for Development in Special Needs Education spoke about the different agency projects and mentioned the UNESCO Salamanca statement and asked the question, 'how do we change our systems so they are inclusive from the beginning?' and made the point that inclusion needs to take account of all peoples and groups.  Amanda emphasised that inclusion is a process, not a state.

Closing Keynote

The final presentation of the conference was made by Yvonne Bonner, Reggio Emilia, Italy.  Yvonne presented a range of very thought provoking images.  She asked the question, 'why work in this area?'  She answered philosophically (and, of course, I paraphrase) that by working in this area  you are considering (and hopefully challenging others to enhance) the rights of all people.  It was a great way to close the conference.

Conference themes

One of the ways that this conference differed from the previous event was that there were more distinct themes.  Whereas the previous event focused quite a lot on an EU project that had just concluded, this conference I felt was slightly more wide ranging (but this could be cause I was more attuned to what to look out for).

One of the more prominent theme were debates surrounding inclusion or exclusion, or more specifically, how to help ensure that people with additional needs could be effectively brought into mainstream education.  This theme was clearly articulated within the opening and closing keynote speeches.  There are differences between countries (and the models of disability that are applied).  Sharing understanding of definitions was certainly a subject that was considered to be important.

Another theme was the need to listen to the individual.  I recall two projects that are aiming to learn more about the experience of individuals.

Quite a few of the presentations related to on-going projects and programmes.  Ideally I would have liked to go away with a more fuller set of conference proceedings to help me remember what was said and recall the arguments that were presented.  Hopefully, as the conference series proceeds, this may be something that the organisers may consider, but hopefully without detracting from an underlying sense that delegates are happy to discuss, share and learn from each others practice.

Addendum

After the conference ended I had some free time.  It was suggested that a fun thing to do would be to go hiking in the Tatra mountains.  I had been told a lot about a town called Zakopane and how it once exerted a strong draw for artists and Bohemians, and how a special cheese was likely to be sold everywhere in the town.  I was not to be disappointed.  As well as having extraordinary mountains and restaurants, tourists walking down the main street would stumble across cheese purveyors (Wikipedia) very thirty or so metres.

My choice of words is no accident, but instead I was embroiled in one.  Rather than literally stumbling across cheese sellers, I literally stumbled down the side of a mountain and broke my arm (although I should add that the stumble was a relatively modest one of about forty or so centimetres).  Visiting the accident and emergency ward was an experience, where a sharp witted paramedic, upon hearing that I was from the UK asked, 'were you walking on the wrong side of the path?'  There were more jokes, but their charm has long since worn away!

The upshot of the accident was that I found myself temporarily disabled, my dominant arm immobilised in plaster.  It all came as a bit of a shock.  Simple tasks suddenly became trials of patience and took considerable longer, if I could figure out how do them at all.  Shoe laces became a liability and shirt buttons became almost impossible.  I had to go about cancelling events and activities that were scheduled for the time after I was to return to the UK.

Upon return to the UK, my motivation levels nose dived. I quickly recalled the universal design principles when doors became difficult to open and jars and cans a frustrating challenge. I also had entered the UK health system, but I had no real sense of who I should ask about information about things.  Whilst monolithic institutions are there to help, individuals are necessary to provide support and peace of mind.

Despite my frustrations, I still had an overwhelming desire to do stuff.  Although I wasn't able to attend a weekend meeting I was scheduled to attend, one of my colleagues from the University of Leeds helped me to participate.  Using Skype text chat, it was possible to take part in a short group discussion activity which helped to lift my mood.  This showed me what a positive impact technology can by providing effective alternative ways of communication.  It also distinctly underlined on of the conference themes: the importance (and power) of inclusion.

I think I'm on the mend now, but I understand it's going to take some time.  All in all, the trip (both to the conference, and over a part of mountain) was an interesting experience.  I've certainly learnt a few things.

I first discovered the notion of learning object granularity when I was tasked with creating my first learning object.  I was using an authoring tool that allowed you to describe (or tag) absolutely anything.  This was a revelation!  My tool allowed me to assign descriptions to individual photographs and sets of navigable pages that could contain any type of digital media you could imagine.  You could also assign descriptions to an entire learning object.  Not only was I struggling with how to use the fields (title, description, keywords) that I had to complete, it was also difficult to know where I should stop!

Terms of reference

There are a significant number of terms here that beg further explanation.  The idea of a learning object (wikipedia) is one that is slippery: it varies depending upon who you speak to.  I see a learning object as one or more digital resources that have the potential to provide useful information to, or serve a useful function for, a consumer.  Consumers, I argue, are both the end-users (learners), and those who might use learning objects within a course of study.

An alternative definition might be: a set of learning resources that can be used together to help a learner achieve a defined set of learning objectives.  I think I prefer this second definition.  It feels a little more precise, but there are few words that allude to how large a learning object might be.

Benefits of learning objects

One of the often cited benefits of learning objects is that they have the potential to be reused.  A digital resource could be taken from one learning situation could be reused (or repurposed) to another situation.  The benefits could include an increase in the quality of the resulting material and possible savings in terms of time and money.

Learning objects are sometimes held within mysterious instruments called repositories.  If existing materials are taken and modified, they could then be later returned to a repository and placed back into circulation for other people can use and modify, thus creating a virtuous cycle.  One problem with placing material in a repository is that if your repository contains tens of thousands of individual objects, finding what you want (to solve your particular teaching need) can become difficult (as well as tedious).

Metadata (wikipedia) has the ability to 'augment’ textual searching, potentially increasing the quality of search results.  Metadata also has the ability to offer you additional information or guidance about what an object might contain and how it might have been used, allowing you to make judgements regarding its applicability in your own teaching context.

There is a paradox: the more granular (or mutable) a learning object is, the more easily it can be reused, but the less useful it is likely to be.  The larger a learning object is, the more useful it is to an individual user (since it may attempt to satisfy a set of learning objectives), and the less likely it could be transferred or 'repurposed' to different learning and teaching contexts or situations.  Furthermore, the smaller the learning object, the more moral fibre one needs to successfully create correct (and relevant) metadata.

Repurposing

'Repurposing' is a funny word. I understand it to mean that you take something that already exists and modify it so it becomes useful for your own situation. I think repurposing is intrinsically difficult.  I don't think it's hard in the sense that it's difficult to change or manipulate different types of digital resources (providing you already have skills to use the tools to effect a change).  I think it's hard because of the inherent dependencies that exist within an object.  You have to remember to take care of all those little details. 

I consider repurposing akin to writing an essay. To write a really good essay you have to first understand the material, secondly understand the question that you are writing about, and then finally, understand who you are writing it for.  If you write an essay that consists of paragraphs which have been composed in such a way that they could be used in other essays, I sense you will end up with an essay that is somewhat unsatisfactory (and rather frustrating to read).

There is something else that can make learning object repurposing difficult.  Learning objects are often built with authoring tools.  Some tools begin with a source document and then spit out a learning object at the other end.  The resulting object may (or may not) contain the source from which it was created.  This is considered to be 'destructive' (or one way) 'authoring', where the resulting material is difficult to modify.

Even if we accept that reuse is difficult, there are other reasons why it is not readily performed.  One reason is that there is no real sense of prestige in using other people materials (but you might get some credit if you find something that is particularly spectacular!).  Essentially, employers don't pay people to re-purpose learning materials; they pay people to convey useful and often difficult ideas of learners in a way that is understandable.  There is no reward structure or incentive to reuse existing material or build material that can be easily reused.  Repurposing takes ingenuity and determination, but within the end result, much of this may be hidden.

There is a final reason why people may like to create and use their own learning resources rather than reuse the work of others.  The very act of creating a resource allows one to acquire an intimate understanding of the very subject that you are intending on teaching.  Creating digital resources is a creative act.  Learning object construction can be constructivism used to prepare for teaching.

Considering metadata granularity

The terms 'aggregate' (or 'composite') and 'atomic' objects are sometimes used when talking about learning objects.  An atomic object, quite simply, are objects  that cannot be decomposed.  An atomic object might well be an image or a sound file, whereas an aggregate object might be a content package or a SCORM object.

In my opinion, many aggregate objects should be considered and treated as atomic objects since it could be far too difficult, complex and expensive to treat them in any other way.  I hold this view since learning objects are ultimately difficult to reuse and repurpose for the reasons presented earlier, but this should not detract from the creation and use of repositories.  Repositories are useful, especially if their use is supported by organisational structures and champions.

I hold the view that metadata should match the size of a resource that it describes.  There should be metadata that describes an object in terms of overall learning objectives.  Lower-level metadata can be used to add additional information to a composite object (such as an image file) that cannot be directly gained from examining its properties or structure (such as using an algorithm to determine its type).

In essence, tagging operations for aggregate and atomic object types must be simple, economic and pragmatic.  If you need to do some tagging to add additional information to a resource (a pragmatic decision), the tagging operation should be simple, and in turn, should be cost effective.

High and low-level metadata tagging

The purpose of high level tagging, the description of high level aggregate object, should be obvious.  Consider a book.  A book has metadata that describes it so it can be found within a library with relative ease (of course, things get more complicated when we consider more complex artefacts, such as journals!).

Low-level (or lower level) metadata may correspond to descriptions of individual pages or images (I should stress at this point, my experience in this area comes from the use of software tools, rather than any substantial period of formal education!).  Why would one want to 'tag' these smaller items (especially if it costs time and money)?  One reason is to provide additional functionality

Metadata helps you to do stuff, just in the same way that storing a book title and list of authors help you to find a book within a library.  Within the EU4ALL project, metadata has the potential to allow you to say that one page (which may contain an audio file) is conceptually equivalent to another page (which contains a textual equivalent).

By describing the equivalence relationships between different resources, the users experience can be optimised to their preferences.  There is also the notion of adaptability, for example, whether a resource can be dynamically changed so it can be efficiently consumed using the device from where it was accessed (this might be a mobile device, a PC, or a PC that is using assistive technology).

Moving forwards

One of the biggest challenges within EU4ALL is to ensure that the users interface to an adaptable learning technology system is coherent, consistent and understandable.  By way of addressing accessibility concerns, all users could potentially benefit.  Learners could potentially be presented with an interface or a sign that indicates that different alternatives are available at certain points during a learning activity, should they be found to exist.  Presenting alternatives in a way that does not cause disruption to learning, yet remains flexible by permitting users to change their preferences, is a difficult task.

Creating metadata is something that is difficult and tiresome (not to mention expensive).  As a result, mistakes can be easily introduced.  Some researchers (slideshare) have been attempting to explore whether it is possible to automatically generate metadata using information about the context in which they are deployed.  In fact, it appears to be a subject of a recent research tender.  But ultimately, humans will be the final consumer of metadata, although metadata languages are intended to be used by machines.

Summary

The notion of a learning object is something that is difficult to define.  Speak to ten different people and you are likely to get ten different answers.  I hold the view that the most useful learning object is an aggregate (or composite) learning object. 

Just as the idea of a learning object can be defined in different ways, the notion of granularity can also have different definitions.  The IEEE LOM standard offers four different levels of 'aggregation', ranging from 1, which refer to 'raw media data' (or media objects), through to individual lessons (level 2), a set of lessons (i.e. a course, level 3), to finally a set of courses which could lead to a formal qualification or certificate (level 4).  I hold the opinion that metadata should match the size of a 'learning object'.  Otherwise, you might end up in a situation where you have to tag everything 'in case it might be used'.  This is likely to be expensive.

High level metadata (in my opinion) is great for storing larger objects within repositories, whereas low-level metadata can be used to describe the adaptability and similarity properties of smaller resources which opens up the possibility of delivering learning resources that match individual user needs and preferences.

Acknowledgements

Posting image: from cocoi_m, from Flick.  Thanks go to an anonymous reviewer whose comments have been very instructive, and all those on the EU4ALL project.  The opinions that are presented here are my own rather than those of the project (or the Open University).

This post describes my second bash at understanding PHP and SOAP webservices, work carried out off and on over the last couple of weeks. The first time I connected PHP to an externally hosted web-service was using a script that I wrote that was external to Moodle. Now my challenge is slightly different: to try to get Moodle calling external web services.

Just to make sure I understand everything, I'm going to present some background acronyms, try and remember what pages I looked at before, then step towards uncovering parts of Moodle that are in some way connected to the magic of web services.

Background information

I'm required to interface to web services that use the SOAP protocol (wikipedia). SOAP is, I am led to believe, an abbreviation for Simple Object Access Protocol. In a nutshell, SOAP allows you to send a message from one computer to another, telling it to do stuff, or asking it a question. In return, you're likely to get a response back that either tells you what you wanted or indicates why your request had failed. SOAP is one of many different techniques that you can use to pass messages to one computer to another over the internet.

Another technique, which is simpler (and faster) but has some limitations that SOAP gets round, is REST (wikipedia). More information on this 'architectural style' can be found quite easily by doing a quick internet search. My focus is, however, SOAP.

So, assuming that one computer exposes (or makes available) a web service to another computer, how do other computers know how to call a service? In other words, what parameters or data does a particular service expect? The answer is that the designers of SOAP service use a language that describes the format of the messages that the SOAP server (or service) will accept. This language is called WSDL, or Web Services Description Language (wikipedia).

Each SOAP server (or service) has a web address. If you need to find out what data a SOAP service requires, you can usually ask it by adding ?wsdl after the service name. This description, which is presented in a computer readable structure, can sometimes help you to build a SOAP call – a request from your computer to another.

Very often (in my limited experience of this area), the production and use of this intermediate language is carried out using layers of software tools and libraries. At one end, you will describe the parameters that you will process, and some magic programming will take your description (which you give in the language of your choice) and convert it into a difficult to read (for humans!) WSDL equivalent. But all this is a huge simplification, of course! And much can (and will) go wrong on the journey to get SOAP web services working.

A web service can be a building block of a Service Oriented Architecture (again, wikipedia), or SOA. In the middle, between different web services you can use the mysterious idea of middleware to connect different pieces of software together to manage the operation of a larger system, but this is a whole level of complexity which I'm very happy to avoid at this point!

Stuff I looked at earlier

The first place that I looked was in a book! Specifically, the PHP Cookbook.

Chapters 14, consuming web services, and 15, building web services looked to be of interest, specifically the sections entitled 'calling a SOAP method with/out WSDL'. Turning to this section I was presented immediately with a number of possibilities of how to make SOAP calls since there are a number of different implementations depending upon the version of PHP that you're using.

Moodle, as far as I understand, can work with version 4.3 of PHP, but moves are afoot to move entirely towards version 5. My reference suggested its perhaps best to use the bundled SOAP extension as opposed to the other (PEAR::SOAP or NuSoap) libraries since they are faster, more compatible with the standards, automatically bundled and exceptions (special case errors) that occur within SOAP are fed into corresponding PHP exception constructs to make programs (theoretically!) easier to read.

Consuming services

On my first attempt to call a web service, I ran into trouble straight after starting! All my code was failing for a mysterious reason and my debugger wasn't deciding to give me anything that was useful. After doing some searching and finding some on-line documentation I gave the PEAR library a try, but ended up just as confused. I ended up asking one of my illustrious colleagues for help who suggested that I should add an additional parameter to original attempts using the PHP extensions to take account of local network setup.

Calling seemed to be quite easy. I could create something called a SOAP client, tell it which address I want to call, give it some options and make a call my sending my client a message which has the same name of the web service which I want to call, optionally loaded up with all my parameters. To see more of what came back, I put some of the client variables in some temporary variables so I could more easily watch what was coming back in my debugger.

Producing services

Now that I (more or less) knew how to call web services using PHP, it struck me that it might be useful to see how it might be possible to present web services using PHP. This was found in the next chapter of the book.

To maintain consistency, I asked the question how might I create some WSDL that describes a service? Unfortunately, there is not an easy answer to this one. Although the integral SOAP libraries don't directly offer support to do this, there are some known techniques and utilities that can help.

One of the big differences between PHP and the WSDL language is that PHP is happy to just go ahead and do things with data without having to know exactly what form (or type) the data takes. You only get into trouble when you ask PHP to carry out operations on a data item that doesn't make sense.

WSDL, on the other hand, describes everything, giving both the name of a data item and its type. Because of this, you can't directly take a PHP data structure and use it to create WSDL. To get round this difference one approach is to provide this additional information in the form of a comment. Although comments are intended to help programmers, they can also be read by other computer programs. By presenting data type information in the form of a comment, an intermediate program can create WSDL structures without too much trouble, saving developer time and heartache. This approach is used by both the NuSoap library and code that works with PHP 5. But I digress...

Moodle web services code

There appear to be some plans to expose some of the Moodle functionality via a series of web services, enabling Moodle to be connected to and used with a range of external applications. There is also a history connecting Moodle with external assessment systems using web services.

A grep through the Moodle codebase (for 1.9) reveals a library called (perhaps unsurprisingly) soaplib. There appears to be some programming logic which makes a decision about which SOAP interface library to use, depending upon the version of PHP: use the native version if PHP 5 is used, otherwise NuSoap.

I'm guessing that the need to use the NuSoap library will gradually disappear at some point, but a guess is totally different from finding out whether this is really going to happen.

One way to find out what is going on and what lies in store for the future is to explore the on-line discussion forums and quickly find a forum that is dedicated to discussing Moodle web services. It appears there are two interesting developments, something called the Moodle NetWork (which allows you to share resources between different instances of Moodle, at a first glance), and non-core Moodle code contribution called the OKTech Web Services. After a little poking around it's possible to find some documentation that describes this development in a little more detail.

I also discovered a documentation page entitled Web services API , but is related to XML-RPC (wikipedia) rather than SOAP. My head is beginning to hurt!

Returning to the Moodle core SOAP library, I ask the question: what uses the soaplib? One way to do this is to search for calls to functions that are contained within this library. I have to confess, I didn't find anything. But, what I did find is a discussion.

It turns out it was added as a result of work carried out at the University of York in the UK for a project called Serving Maths that created something called the Remote Question Protocol (RQP). The initial post mentions concerns about not being able to make use of some of the additional parameters that the PHP 5 library provides. This is a concern that I share.

Next steps

I've more or less finished my whistlestop tour of Moodle components and code that relate to web services type stuff. I'm sure there is more lurking out there that I haven't discovered yet. But what of a conclusion?

Since I'm not planning on using Moodle to expose any web services I can thankfully sidestep some of the more difficult discussions I've uncovered.

Also, since there isn't much in the way of existing SOAP utility code that I can build upon and I roughly know more or less how to call web services using the magic functions that are provided in PHP 5, I'm going to try to more or less directly add some lines of code to Moodle. But before I do this, like every good developer, I'll test things out using a test harness to explore how my target services behave.

Image: modified from wikipedia

As a part of the EU4ALL project, I have been trying to figure out how to add a new resource type. The idea is to add a resource known as an 'adaptable resource', whereby different media types are presented to the user depending on their accessibility preferences. The issue of how and where to assign or change these preferences is currently a question that has to be resolved. This post is intended as a bunch of 'notes to self' about what I have found during the last couple of days exploring and poking around the Moodle code base.

To explore the code, I've been using a couple of tools: SQLYog, which was recommended to me by an illustrious IET developer (to allow me to explore an instance of a Moodle MySQL database I have running on my home machine), and NuSphere, a PHP IDE. I did try the Zend IDE a year or so back, but abandoned it since I became rather confused!

So, how is it possible to add a new resource to Moodle? Initially, I decided to look at an existing resource, beginning with the simplest one that I could find: a simple text resource. By browsing the code base I seemed to find the rough area where the 'resource code' lives. I also browsed around the developer documentation page an unearthed a resource class template. Great!

In development, one question instantiates a tree of others. The most fundamental question is: how does this code work? I need to answer this big one to make a change. This is too big, so I split it into two other questions: (1) how can you modity a form that allows you to enter the parameters that describe an adaptable resource (currently it is to be a simple numerical value, from what I understand), and (2) how can I take the values held within a form and update them to the MySQL database? This requires an understanding of further magic code. As a note to myself, let's have a look at each of these in turn.

Entering stuff

Looking at the text resource code, there seemed to be a bit of object-oriented polymorphism going on. The name of the directory where the resource code is important too! There is a magic function called display which appears to make some further magic calls to create some data entry fields - but these calls are quite a long way away from the pure HTML that is presented in the browser window.

This is another question: how does the magic functions in display() get turned into HTML? The answer apparently lies with the application of a forms library called PERL. If I figure out how to add functions in a way that would work for this library, I can ask the user for whatever I want.

The form uses some object-oriented principles. Individual controls are added to 'the form', and then a function is executed that 'prints out' or renders each of the controls, without you having to go near to producing your own HTML.

Another interesting observation, is that the display function I have uncovered only relates to a small part of a bigger form. This is due to subclassing and polymorphism that is being used, but this is a distraction... now I have a little understanding of what is happening (thanks to the NuSphere debugger!), I'll park this question for the time being. There are other mysterious areas to explore!

Storing stuff

When a Moodle user edits a course resource, there are a couple of buttons that appear at the bottom of the screen. These are 'save and return', 'save and display' and 'cancel'. Looking at these buttons from a HCI perspective I think, 'buttons doing two different things?? surely this is a bad idea!'. But I digress.

My question is, 'what happens when the tutor (or administrator) clicks on either of the save buttons - where does the data go? Or more precisely, how does the data get saved?

Moodle seems to have a thin database layer: a set of functions that allows you to send SQL statements and receive data in response. Since the contents of the resource form is held in what can only be described as a 'big variable' (PHP has a funny approach to object-oriented programming if you've used other languages), the Moodle developers have figured out a way to transfer the contents of a form to the database, by matching on-screen fields to database fields.

This seems to work well: but on the downside is the database update code that Moodle code generates appear to be rather big, and an implicit dependency is created between the form and the database structure. Other systems that I've looked at make use of stored procedures, which has the potential to boost performance and security on one hand, but on the other restrict the database platforms that an application can be used with.

Moving forwards

Now I know (roughly) how to add extra bits to a new resource type, the next thing I have to do is figure out how to write the functions that I need. After I've done that I'll have to hook up my edits to the database, and figure out how to best display the data that I've produced. I already have some idea about how to do this since I have created a paper prototype.

But before going down that road, I think I'll continue my survey of the Moodle codebase by exploring what sections can potentially relate to adding and manipulation of user parameters and settings. I think I'll start by looking at the user profile developer pages.

Looking towards the longer term, I will also have to connect Moodle to a number of different web services. Wish me luck!