Articles

After installing the RTL-SDR on my Clockwork uConsole (running a Raspberry Pi CM4) I was looking for something to try out the device to see what it could do. The GNU Radio Companion is still a bit baffling at the moment so I was searching for something with a lower barrier to entry.

One thing that caught my eye was a project on GitHub called dump1090. This is a "Mode S" decoder that uses the RTL-SDR to decode transponder information from Aircraft. Whilst the package is quite old now, it is still being minimally maintained. The dependencies are quite small and so it tends to compiles quite nicely without too many additional packages or issues, event on the limited hardware of the CM4.

I've seen lots of "our team" pages over the years, but one of the ones that stood out to me the most were those that had an interactive element to them. For me, it adds a bit of personality to the page and makes it feel more alive than a bunch of silhouettes of the directors.

I remember seeing a team page a while ago that had a number of little images of the team that looked at the mouse pointer as it moved around the page. Each face in the picture looked in all 8 directions as my mouse pointer went around the screen. This caught my interest so I had a look to see how it worked.

The page used a combination of a fixed image dimension and background positioning to show show parts of a single image. By combining this with a little bit of JavaScript the page created an interactive image without having to load lots of images. The image can also be simple as it just needs to be a square collage of 9 images, one for each direction the mouse lies in, and a central one to look straight ahead.

I was scrolling through The Pi Hut website recently and my eye was drawn by a case for the Raspberry Pi Computer Module 4 (CM4) that looked like a modified Nintendo Gameboy. I had bought a CM4 for another project, but as that project wouldn't be delivered for a few months I was looking for something useful to do with the CM4 in the meantime.

The GPi Case 2 from Retroflag is a case that accepts the Raspberry Pi Compute Module 4 (CM4) and is used as an emulation station. Using the right software, it is possible to add files to the system that allow you to play games from a variety of different platforms. If you go for the WiFi CM4 you can also connect Bluetooth controllers to the unit and even use WiFi to transfer files.

DrupalCamp Scotland returned after a small hiatus of 5 years on the 25th October 2024 and saw nearly 50 people attend the university of Edinburgh Paterson's Land building for a day of talks and sessions. I had the honor of being invited to speak at the conference, which was the first physical speaking session I've had since 2019.

I arrived early to the conference on a sunny Friday morning after driving up the night before. After a cup of coffee and a lovely chat with a few people we started the conference.

This is the sixth article in a series of articles about the Batch API in Drupal. The Batch API is a system in Drupal that allows data to be processed in small chunks in order to prevent timeout errors or memory problems.

So far in this series we have looked at creating a batch process using a form, followed by creating a batch class so that batches can be run through Drush, using the finished state to control batch processing, processing CSV files through a batch process and finally adding to running batch processes. These articles give a good grounding of how to use the Drupal Batch API.

In this article we will look at how the Batch API is used within Drupal. The Batch API in Drupal is either used to perform a task, which I will call "direct", or to pass on the batch operations to a hook, which I will call "indirect". These aren't official terms you understand, I'm just using them here to separate how Drupal uses the Batch API.

This is the fifth article in a series of articles about the Batch API in Drupal. The Batch API is a system in Drupal that allows data to be processed in small chunks in order to prevent timeout errors or memory problems.

So far in this series we have looked at creating a batch process using a form, followed by creating a batch class so that batches can be run through Drush, using the finished state to control batch processing and then processing CSV files through a batch process. All of these articles give a good grounding of how to use the Drupal Batch API.

In this article we will take a closer look at how the batch system processes items by creating a batch run inside an already running batch process. This will show how batch systems run and what happens when you try to add additional operations to a running batch.

This is the fourth article in a series of articles about the Batch API in Drupal. The Batch API is a system in Drupal that allows data to be processed in small chunks in order to prevent timeout errors or memory problems.

So far in this series we have looked at creating a batch process using a form, followed by creating a batch class so that batches can be run through Drush and then using the finished state to control batch processing. All of these articles go together to form a basis of batch processing in Drupal.

In this article we will look at bringing these concepts together to perform a task that is quite common on websites, processing Comma Separated Value or CSV files, which we will do using the Drupal Batch API.

This is the third article in a series of articles about the Batch API in Drupal. The Batch API is a system in Drupal that allows data to be processed in small chunks in order to prevent timeout errors or memory problems.

So far in this series we have looked at creating a batch process using a form and then creating a batch class so that batches can be run through Drush. Both of these examples used the Batch API to run a set number of items through a set number of process function callbacks. When setting up the batch run we created a list of items that we wanted to process and then split this list up into chunks, each chunk being sent to a batch process callback.

There is another way to set up the Batch API that will run the same number of operations without defining how many times we want to run them first. This is possible by using the "finished" setting in the batch context.

This is the second part of a series of articles looking at the Batch API in Drupal. The Batch API is a system in Drupal that allows data to be processed in small chunks in order to prevent timeout errors or memory problems.

In the previous article we looked at how to setup the batch process using a form, with the batch methods being contained within the structure of the form class. When the form was submitted the batch process ran through 1,000 items and then printed out a result at the end.

Whilst there is nothing wrong with running the Batch API with everything in a form class, it is normally better to abstract the batch processing code into a separate class.

The Batch API is a powerful feature in Drupal that allows complex or time consuming tasks to be split into smaller parts.

For example, let's say you wanted to run a function that would go through every page on you Drupal site and perform an action. This might be removing specific authors or removing links in text. You might create a small loop that just loads all pages and performs the action on those pages.

This is normally fine on sites that have a small number of pages, like under 100 pages. But what happens when the site has 10,000 pages, or a million? Your little loop will soon hit the limits of PHP execution times or memory limits and cause the page to be terminated. How do you know how far your loop progressed through the data? What happens if you tried to restart the loop?