Category Archives: Other

Getting data from wikidata into WordPress custom taxonomy

I created a custom taxonomy to use as an index of people mentioned. I wanted it to work nicely as linked data, and so wanted each term in it to refer to the wikidata identifier for the person mentioned. Then I thought, why not get the data for the terms from wikidata?

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TIL: getting Skype for Linux working

Microsoft’s Skype for Linux is a pain for Linux (well, for Ubuntu at least). It stopped working for me, no one could hear me.

Apparently it needs pulse audio to  work properly, but as others have found “most problems with the sound in Linux can be solved by removing PulseAudio”. The answer, as outlined in this post, is apulse “PulseAudio emulation for ALSA”.

Wikidata driven timeline

I have been to a couple of wikidata workshops recently, both involving Ewan McAndrew; between which I read Christine de Pizan‘s Book of the City of Ladies(*). Christine de Pizan is described as one of the first women in Europe to earn her living as a writer, which made me wonder what other female writers were around at that time (e.g. Julian of Norwich and, err…). So, at the second of these workshops, I took advantage of Ewan’s expertise, and the additional bonus of Navino Evans cofounder of Histropedia  also being there, to create a timeline of medieval European female writers.  (By the way, it’s interesting to compare this to Asian female writers–I was interested in Christina de Pizan and wanted to see how she fitted in with others who might have influenced her or attitudes to her, and so didn’t think that Chinese and Japanese writers fitted into the same timeline.)

Histropedia timeline of medieval female authors (click on image to go to interactive version)

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An ending, and a beginning

On 30 June 2017 I will be leaving my current employment at Heriot-Watt University. I aim to continue to support the use of technology to enhance learning as an independent consultant.

I first joined Heriot-Watt’s Institute for Computer Based Learning in 1996 on a six month secondment. I was impressed that ICBL was part of a large, well-supported Learning Technology Centre–which was acknowledged at that time as one of the leading centres for the use of technology in teaching and learning. You can get a sense of the scope of the LTC by looking at the staff list from around that time. Working with, and learning from, colleagues with this common interest was hugely appealing to me; so when I had the opportunity I re-joined ICBL in 1997, and this time I stayed.

In my time at Heriot-Watt I have been fortunate beyond belief to collaborate with people in ICBL and through work such as the Engineering Subject Centre (and other subject centres of the LTSN and then HE Academy), EEVL, Cetis and many Jisc projects. But things change. The LTC was dismantled. A reduced ICBL moved to be a part of the Computer part of the School of Mathematics and Computer Sciences (MACS). Funding became difficult, and while I greatly appreciate the huge effort made by several individuals which kept me in continuous employment, like many in similar roles I frequently felt my position was precarious.  I really enjoyed teaching Computer Science and Information Systems students, and I worked with some great people in MACS, but the work became more internally focused, isolated from current developments…not what I had joined ICBL for.

What next?

When Heriot-Watt announced that it planned to offer staff voluntary severance terms, I applied and was happy to be accepted. My professional interests remain the same: supporting the selection and use appropriate learning resources; supporting the management and dissemination of learning resources; open education; sharing and learning. I do this through work on resource description, course description, OER platforms, I use specific technologies like schema.org, LRMI and wordpress. I intend to continue working in these areas, as an independent consultant and with colleagues in Cetis LLP. Contact me if you think I can help you.

Photograph of a person up a flight of stairs into the open. by flickr user Allen, licensed CC:BY.
Exit, by Allen ( https://www.flickr.com/photos/78139009@N03/) Licence CC:BY. Click image for original.

CMALT – Another open portfolio

I’ve finally made a start on drafting my CMALT Portfolio (and so has Lorna,* we’re writing buddies), and in the interests of open practice I’m going to attempt to write the whole thing as an open Google doc before moving it here on my blog.  I have a shared folder on Google Drive, Phil’s CMALT, where I’ll be building up my portfolio over the coming weeks.  I’ve made a start drafting the first two Core Areas:  Operational Issues and Learning Teaching and Assessment, I’ll be adding more sections shortly, I hope. I’d love to have some feedback on  my portfolio so if you’ve got any thoughts, comments or guidance I’d be very grateful indeed.  I’d also be very interested to know if anyone else has created their portfolio as an exercise in open practice, and if so, how they found the experience.

Wish me luck!

An open door and the word Openness, in ALT branding.
CC BY @BryanMMathers for ALT

*Credit: This post is totally copied from Lorna’s post, with slight adaptation, under the terms of the Creative Commons Attribution 3.0 Unported License she used.

More importantly, she let me copy her idea as well. That’s open practice which can’t be formally licensed, though I know that she is cool with it.

Flying cars, digital literacy and the zone of possibility

Where’s my flying car? I was promised one in countless SF films from Metropolis through to Fifth Element. Well, they exist.  Thirty seconds on the search engine of your choice will find you a dozen of so working prototypes (here’s a YouTube video with five).

A fine and upright gentle man flying in a small helicopter like vehicle.
Jess Dixon’s flying automobile c. 1940. Public Domain, held by State Library and Archives of Florida, via Flickr.

They have existed for some time.  Come to think about it, the driving around on the road bit isn’t really the point. I mean, why would you drive when you could fly. I guess a small helicopter and somewhere to park would do.

So it’s not lack of technology that’s stopping me from flying to work. What’s more of an issue (apart from cost and environmental damage) is that flying is difficult. The slightest problem like an engine stall or bump with another vehicle tends to be fatal. So the reason I don’t fly to work is largely down to me not having learnt how to fly. Continue reading

Shared WordPress archive for different post types

In a WordPress plugin I have custom post types for different types of publication: books, chapters, papers, presentations, reports. I want one single archive of all of these publications.

I know that the theme template hierarchy allows templates with the pattern archive-$posttype.php, so  I tried setting the slug for all the custom post types to ‘presentations’. WordPress doesn’t like that.  So what I did was set the slug for one of the publication custom post types to ‘presentations’, that gives me a /presentations/ archive for that custom post type(1). I then edited the archive.php file to use a different  template parts for custom post types(2):

<?php $cpargs = array('_builtin' => False,
				  'exclude_from_search' => False);
	$custom_post_types = get_post_types( $cpargs, 'names', 'and' );
	if ( is_post_type_archive( $custom_post_types ) ) {
		get_template_part( 'archive-publication' );
	} else {
		get_template_part( 'archive-default' );
	}  
?>

See anything wrong with this approach? Any comments on how better to do this would be welcome.

Notes:
  1. 1 could edit the .htaccess file to redirect the /books/, /chapters/ …etc archives to /publications/, which would be neater in some ways but would make setting up the theme a bit of a faff.
  2. Yes, the code gives all the custom post types with an archive the same archive. That’s fixable if you make the array of post types for which you want a shared archive manually.

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 schema.org 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', 'http://example.org/blog' );
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="http://example.org/blog" WHERE option_name = "home";
SELECT * FROM wp_options WHERE option_name = 'siteurl';
UPDATE wp_options SET option_value="http://example.org/blog" 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.