Three resources for custom metadata in WordPress

When developing WordPress for use as a CMS one approach I have used is to create a custom post type for each type of resource and custom metadata boxes for relevant properties of those types.  I’ve used that approach when exploring the possibility of using WordPress as a semantic web platform to edit metadata, when building course information pages for students and am doing so again in updating some work I did on WordPress as a lightweight repository.  Registering a custom post type is pretty straightforward, follow the example in the codex page, I found handling custom metadata boxes a little more difficult. Here are three resources that helped.

Doing it long hand

It’s a few years old, but I found Justin Tadlock’s Smashing Magazine article How To Create Custom Post Meta Boxes In WordPress really useful as a clear and informative tutorial. It was invaluable in understanding how metaboxes work. If I had only wanted one or two simple text custom metadata fields then coding them myself would be an option, but I found a couple of problems. Firstly, I was repeating the same code too many times. Secondly when I thought about wanting to store dates or urls or links to other posts, with suitable user interface elements and data validation, I could see the amount of code needed was only going to increase. So I looked to see whether any better programmers than I had created anything I could use.

Using a helper plugin

I found two plugins that promised to provide a framework to simplify the creation of metaboxes. These are not plugins that provide anything that the end user can see directly, rather they provide functions that can be used in theme an plugin development. They both reduce the work of creating a metabox down to creating an array with the properties you want the metabox to have. They both introduce a dependency on code I cannot maintain, which is something I am always cautious about in using third-party plugins, but it’s much more viable than the alternative of creating such code from scratch and maintaining it myself.

CMB2 is “a metabox, custom fields, and forms library for WordPress that will blow your mind.” It is free and open source, with development hosted on GitHub.  It seems quite mature (version 1.0 was in Nov 2013), with a large installation base and decent amount of current activity on github.

Meta Box is “a powerful, professional developer toolkit to create custom meta boxes and custom fields for WordPress.” It too is free and released under GPL2 licence, but there are paid-for extensions (also GPL2 licensed) and I don’t see any open source development (I may not have looked in the right place).  Meta box has been around for a couple of years, is regularly updated and has a very large user base. The paid-for extensions give me some hope that the developers have a sustainable business model, but a worry that maybe ‘free’ doesn’t include the one function that at sometime I will really need. Well, developers cannot live on magic beans so I wouldn’t mind paying.

In the end both plugins worked well, but Meta Box allows the creation of custom fields for a link from one post to another, which I didn’t see in CMB2. That’s what I need for a metadata field to say that the author of the book described in one post is a person described in another.

Cloning WordPress sites for development

I do just enough theme and plugin development on WordPress to need an alternative to using a live WordPress site for development and testing, but at the same time I want to be testing on site as similar to the live site as possible. So I set up clones of WordPress sites either on my local machine or a server for development and testing. (Normally I have clones on the localhost server of couple of machines I use for development and another clone on a web accessible testing or staging server for other people to look at.) I don’t do this very often, but each time I do it I spend as much time trying to remember what it is I need to do as it actually takes to do it. So here, as much as an aide-memoire for myself as anything, else I’ve gathered it all in one place. What I do is largely based on the Moving WordPress information in the codex, but there are a couple of things that doesn’t cover and a couple of things I find it easier to do differently.

Assuming that the pre-requisites for WordPress are in place (i.e. MySQL, webserver, PHP), there are three stages to creating a clone. A. copy the WordPress files to the development site; B. clone the database; C. fix the links between WordPress and the database for the new site. A and B are basically creating backup copies of your site, but you will want to make sure that whatever routine backups you use are up to date and ready to restore in case something goes wrong. Also, this assumes that you are notwant to clone just one site on a WordPress Multisite installation.

Copying the WordPress files

Simply copy all the files from the folder you have WordPress installed in, and all the sub-folders to where you want the new site to be. This will mean that all the themes, plugins and uploaded media will be the same on both sites. Depending on whether the development site is on the same server as the main site I do this either with file manager or by making a compressed archive and ftp. Make sure the web server can read the files on the dev site (and write to the relevant folders if that is how you upload media, plugins and themes).

Cloning the database

First I create a new, blank database on for the new site, either from the command line or using something like MySQL Database Wizard which my hosting provider has on CPanel. I create a new user with full access to that data base–the username and password for this user will be needed to configure WordPress with access to this database. If you have complete control of over the database name and user name then use the same name username and password as is in the wp-config.php file of the site you are cloning. Otherwise you can change these later.

Second, I use PHP MyAdmin to export the data base from the original site and import it to the one on which you are making a clone.

phpMyAdmin Export screen

Fix all the bits that break

All that remains is to reconnect the PHP files to the database and fix a few other things that break. This is where it get fiddly. Also, from now on be really careful about which site you are working on: they look the same and you really don’t want to set up your public site as a development server. Make all these changes on the new development site.

In wp-config.html (it’s in the top of the WordPress folder hierarchy) find the following lines and change the values to be those for your new development server and database.

define( 'WP_CONTENT_URL', '' );
define( 'WP_CONTENT_DIR', 'path/to/wp-content' );

define('DB_NAME', 'databaseName');

/** MySQL database username */
define('DB_USER', 'databaseUserName');

/** MySQL database password */
define('DB_PASSWORD', 'password');

You might also need to change the value for DB_HOST

Then you need to change the options that WordPress stores in the database. Normally you do this through the WordPress admin interface, but this is not yet available on your new site. There are various ways you can do this, I change the url directly in the data base with PHPMyAdmin, either by direct editing as described in the codex page or from the command line as described here.

mysql -u root -p

USE databaseName
SELECT * FROM wp_options WHERE option_name = 'home';
UPDATE wp_options SET option_value="" WHERE option_name = "home";
SELECT * FROM wp_options WHERE option_name = 'siteurl';
UPDATE wp_options SET option_value="" WHERE option_name = "siteurl";

You should now have access to the new cloned site, though some things will still be misbehaving.

You will probably have the old site’s URL in various posts and GUIDs. I use the better search replace plugin to fix these.

iesiesIf you do any fancy redirects with .htaccess, make sure that these are written in such a way that works for the new URL.

If you are using Jetpack you will need to use it in safe mode if the development server is connected to the web or development mode if running on localhost. (This is a bit of a pain if you want to test Jetpack settings.)

On a development site you’ll probably want to add this to wp-config.php:

define('WP_DEBUG', true);

If you are running a development or testing server on a web accessible site you probably want to restrict who has access to it. I use the My private site plugin so that only site admins have access.

Keeping in sync

While it’s not entirely necessary that a development or testing site be kept completely in sync with the main one, it is worth keeping them close so that you don’t get unexpected issues on the main site. You can manually update the plugins and themes, and use the wordpress export / import plugins to transfer new content from the live site to the clone. Every now and again you might want to re-clone the site afresh. Something I find useful for development and testing of new plugins and themes is to have the plugin or theme directory that I am developing in set up as a git repository linked to github and keep files in sync with git push and git pull.

Anything else?

I think that is it. If I have forgotten anything or if you have tips on making any of this easier please leave a comment.

Three resources about gender bias

These are three resources that look like they might be useful in understanding and avoiding gender bias. They caught my attention because I cover some cognitive biases in the Critical Thinking course I teach. I also cover the advantages of having diverse teams working on problems (the latter based on discussion of How Diversity Makes Us Smarter in SciAm). Finally, like any responsible  teacher in information systems & computer science I am keen to see more women in my classes.

Iris Bohnet on BBC Radio 4 Today programme 3 January.  If you have access via a UK education institution with an ERA licence you can listen to the clip via the BUFVC Box of Broadcasts.  Otherwise here’s a quick summary. Bohnet stresses that much gender bias is unconscious, individuals may not be aware that they act in biased ways. Awareness of the issue and diversity training is not enough on its own to ensure fairness. She stresses that organisational practise and procedures are the easiest effective way to remove bias. One example she quotes is that to recruit more male teachers job adverts should not “use adjectives that in our minds stereotypically are associated with women such as compassionate, warm, supportive, caring.” This is not because teachers should not have these attributes or that men cannot be any of these, but because research shows[*] that these attributes are associated with women and may subconsciously deter male applicants.

[*I don’t like my critical thinking students saying broad and vague things like ‘research shows that…’. It’s ok for 3 minute slot on a breakfast news show but I’ll have to do better. I hope the details are somewhere in Iris Bohnet, (2016). What Works: Gender Equality by Design]

This raised a couple of questions in my mind. If gender bias is unconscious, how do you know you do it? And, what can you do about it? That reminded me of two other things I had seen on bias over the last year.

An Implicit Association Test (IAT) on Gender-Career associations, which  I took a while back. It’s a clever little test based on how quickly you can classify names and career attributes. You can read more information about them on the Project Implicit website  or try the same test that I did (after a few disclaimers and some other information gathering, it’s currently the first one on their list).

A gender bias calculator for recommendation letters based on the words that might be associated with stereotypically male or female attributes. I came across this via Athene Donald’s blog post Do You Want to be Described as Hard Working? which describes the issue of subconscious bias in letters of reference. I guess this is the flip side of the job advert example given by Bohnet. There is lots of other useful and actionable advice in that blog post, so if you haven’t read it yet do so now.

Book chapter: Technology Strategies for Open Educational Resource Dissemination

A book with a chapter by Lorna M Campbell and I has just been published. The book is Open Education: International Perspectives in Higher Education edited by Patrick Blessinger and TJ Bliss, published by Open Book Publishers.

There are contributions by people I know and look up to in the OER world, and some equally good chapters by folk I had not come across before. It seems to live up to its billing of offering an international perspective by not being US-centric (though it would be nice to see more from S America, Asia and Africa), and it provides a wide view of Open Education, not limited to Open Education Resources. There is a foreword by David Wiley, a chapter on a human rights theory for open education by the editors, one on whether emancipation through open education is theory or rhetoric by Andy Lane. Other people from the Open University’s Open Education team (Martin Weller, Beatriz de los Arcos, Rob Farrow, Rebecca Pitt and Patrick McAndrew) have written about identifying categories of OER users.  There are chapters on aspects such as open science, open text books, open assessment and credentials for open learning; and several case studies and reflections on open education in practice.

Open Education: International Perspectives in Higher Education is available under a CC:BY licence as a free PDF, as very cheap mobi or ePub, or reasonably priced soft and hard back editions. You should get a copy from the publishers.

Technology Strategies for OER

The chapter that Lorna and I wrote is an overview drawing on our experiences through the UKOER programme and our work on LRMI looking at managing the dissemination and discovery of open education resources. Here’s the abstract in full, and a link to the final submitted version of our chapter.

This chapter addresses issues around the discovery and use of Open Educational Resources (OER) by presenting a state of the art overview of technology strategies for the description and dissemination of content as OER. These technology strategies include institutional repositories and websites, subject specific repositories, sites for sharing specific types of content (such as video, images, ebooks) and general global repositories. There are also services that aggregate content from a range of collections, these may specialize by subject, region or resource type. A number of examples of these services are analyzed in terms of their scope, how they present resources, the technologies they use and how they promote and support a community of users. The variety of strategies for resource description taken by these platforms is also discussed. These range from formal machine-readable metadata to human readable text. It is argued that resource description should not be seen as a purely technical activity. Library and information professionals have much to contribute, however academics could also make a valuable contribution to open educational resource (OER) description if the established good practice of identifying the provenance and aims of scholarly works is applied to learning resources. The current rate of change among repositories is quite startling with several repositories and applications having either shut down or having changed radically in the year or so that the work on which this contribution is based took. With this in mind, the chapter concludes with a few words on sustainability.

Preprint of full chapter (MS Word)

Reflective learning logs in computer science

Do you have any comments, advice or other pointers on how to guide students to maintaining high quality reflective learning logs?

Context: I teach part of a first year computer science / information systems course on Interactive Systems.  We have some assessed labs where we set the students fixed tasks to work on, and there is coursework. For the coursework the students have to create an app of  their own devising. They start with something simple (think of it as a minimum viable product) but then extend it to involve interaction with the environment (using their device’s sensors), other people, or other systems. Among of the objectives of the course are that: students learn to take responsibility for their own learning,  to appreciate their own strengths and weaknesses, and what is possible within time constraints. We also want students to gain experience in conceiving, designing and implementing an interactive app, and we want them to reflect on and provide evidence about the effectiveness of the approach they took.

Part of the assessment for this course is by way of the students keeping reflective learning logs, which I am now marking.  I am trying to think how I could better guide the students to write substantial, analytic posts (including how to encourage engagement from those students who don’t see the point to keeping a log).

Guidance and marking criteria

Based on those snippets of feedback that I found myself repeating over and over, here’s what I am thinking to provide as guidance to next year’s students:

  • The learning log should be filled in whenever you work on your app, which should be more than just during the lab sessions.
  • For set labs entries with the following structure will help bring out the analytic elements:
    • What was I asked to do?
    • What did I anticipate would be difficult?
    • What did I find to be difficult?
    • What helped me achieve the outcome? These may be resources that helped in understanding how to do the task or tactics used when stuck.
    • What problems could I not overcome?
    • What feedback did I get from teaching staff and other students?
    • What would I do differently if I had to do this again?
  • For coursework entries the structure can be amended to:
    • What did I do?
    • What did I find to be difficult? How did this compare to what I anticipated would be difficult?
    • What helped me achieve the outcome? These may be resources that helped in understanding how to do the task or tactics used when stuck.
    • What problems could I not overcome?
    • What feedback did I get from teaching staff and other students on my work so far?
    • What would I do differently if I had to do this again?
    • What do I plan to do next?
    • What do I anticipate to be difficult?
    • How do I plan to overcome outstanding issues and expected difficulties.

These reflective learning logs are marked out of 5 in the middle of the course and again at the end (so represent 10% of the total course mark), according to the following criteria

  1. contributions: No entries, or very brief (i.e. one or two sentences) entries only: no marks. Regular entries, more than once per week, with substantial content: 2 marks.
  2. analysis: Brief account of events only or verbatim repetition of notes: no marks. Entries which include meaningful plans with reflection on whether they worked; analysis of problems and how they were solved; and evidence of re-evaluation plans as a result of what was learnt during the implementation and/or as a result of feedback from others: 3 marks.
  3. note: there are other ways of doing really well or really badly than are covered above.


Am I missing anything from the guidance and marking criteria?

How can I encourage students who don’t see the point of keeping a reflective learning log? I guess some examples of where they are important with respect to professional practice in computing.

These are marked twice, using rubrics in Blackboard, in the middle of the semester and at the end. Is there any way of attaching two grading rubrics to the same assessed log in Blackboard? Or a workaround to set the same blog as two graded assignments?

Answers on a postcard… Or the comments section below. Or email.

XKCD or OER for critical thinking

I teach half a course on Critical Thinking to 3rd year Information Systems students. A colleague takes the first half which covers statistics. I cover how science works including the scientific method, experimental design, how to read a research papers, how to spot dodgy media reports of science and pseudoscience, and reproducibility in science; how to argue, which is mostly how to spot logical fallacies; and a little on cognitive development. One the better things about teaching on this course is that a lot of it is covered by xkcd, and that xkcd is CC licensed. Open Education Resources can be fun.

how scientists think


hypothesis testing

Hell, my eighth grade science class managed to conclusively reject it just based on a classroom experiment. It's pretty sad to hear about million-dollar research teams who can't even manage that.


Blind trials


Interpreting statistics


p hacking


Confounding variables

There are also a lot of global versions of this map showing traffic to English-language websites which are indistinguishable from maps of the location of internet users who are native English speakers





Confirmation bias in information seeking



undistributed middle


post hoc ergo propter hoc

Or correlation =/= causation.

He holds the laptop like that on purpose, to make you cringe.



Bandwagon Fallacy…

…and fallacy fallacy


Diversity and inclusion


 Licence: All xkcd are by Randall Munroe and licensed under a Creative Commons Attribution-NonCommercial 2.5 License. This means you’re free to copy and share these comics (but not to sell them). More details.

[Updated 15/11/2016 to add full source & licence info and some links, which I really ought to have known better than to forget.]