Using Google interactive charts and WordPress to visualise data
This is a rare techy post (and those of you who know me will also know that my techy competence is not so great so apologies for any mistakes).
Along with a university partner, Pontydysgu bid for a small contract to develop a system to allow the visualisation of labour market data. The contractors had envisaged a system which would update automatically from UK ONS quarterly labour market data: a desire clearly impossible within the scope of the funding.
So the challenge was to design something which would make it easy for them to manually update the data with visualisations being automatically updated from the amended data. Neither the contractors or indeed the people we were working with in the university had any great experience of using visualisation or web software.
The simplest applications seemed to me to be the best for this. Google spreadsheets are easy to construct and the interactive version of the chart tools will automatically update when embedded into a WordPress bog.
Our colleagues at the university developed a comprehensive spreadsheet and added some 23 or so charts. So far so good. Now was the time to develop the website. I made a couple of test pages and everything looked good. I showed the university researchers how to edit in WordPress and how to add embedded interactive charts. And that is where the problems started. They emailed us saying that not only were their charts not showing but the ones i had added had disappeared!
The problem soon became apparent. WordPress, as a security feature, strips what it sees as dangerous JavaScript code. We had thought we could get round this by using a plug in called Raw. However in a WordPress multi-site, this plug in will only allow SuperAdmins to post unfiltered html. This security seems to me over the top. I can see why wordpress.com will prevent unfiltered html. And I can see why in hosted versions unfiltered html might be turned off as a default. But surely, on a hosted version, it should be possible for Superadmins to have some kind of control over what kind of content different levels of users are allowed to post. The site we are developing is closed to non members so we are unlikely to have a security risk and the only Javascript we are posting comes from Google who might be thought to be trusted.
WordPress is using shortcodes for embeds. But there are no shortcodes for Google Charts embed. There is shortcode for using the Google Charts API but that would invalidate our aim of making the system easy to update. And of course, we could instead post an image file of the chart, but once more that would not be dynamically updated.
In the end my colleague Dirk hacked the WordPress code to allow editors to post unfiltered html but this is not an elegant answer!
We also added the Google code to Custom Fields allowing a better way to add the embeds.
Even then we hot another strange and time wasting obstacle. Despite the code being exactly the same, code copied and posted by our university colleagues was not being displayed. The only difference in the code is that when we posted it it had a lot of spaces, whist theirs appeared to be justified. It seems the problem is a Copy/ Paste bug in Microsoft Explorer 9, which is the default bowser in the university, which invalidates some of the javascript code. The work around for this was for them to install Firefox.
So (fingers crossed) it all works. But it was a struggle. I would be very grateful for any feedback – either on a better way of doing what we are trying to achieve – or on the various problems with WordPress and Google embed codes. Remember, we are looking for something cheap and easy!
