Revisiting my spotviz.info webapp: visualizing WSJT-X FT8 spots over time – part 4: It’s back, it’s alive! http://www.spotviz.info

I still have some refactoring to do as I move the app to the cloud, but as the first starting point I have the original app up and running on WildFly on a VPS. It’s back up and live on the original domain, http://www.spotviz.info

The uploader has been updated to read current 2.x WSJT-X log files, but I haven’t uploaded the .jar to GitLab yet, but I’ll do that soon. I’ve some test log data uploaded under my callsign, KK6DCT.

More changes to come soon.

If you’re catching up, here’s my previous posts on getting the project up and running again:

Revisiting my spotviz.info webapp: visualizing WSJT-X FT8 spots over time – part 3: Successful deployment: visualizing 20m spots from 9am to 10pm

I’ve successfully deployed my SpotViz app on WildFly running locally and tested running a visualization playback of FT8 signals received during a whole day, from 9am to 10pm. It’s interesting to see the propagation move from my location on the US West coast out to the East coast, and then gradually move West during the day, following the sun, until the propagation dies out on 20m completely around 10pm.

Here’s a screen capture of the playback:

Next up, I’ll be setting this up hosted on a VPS somewhere, and start working on some of the bugs in the UI.

Deploying a Jersey based web app to WildFly 8 (part 1)

I’ve been resuscitating a personal Amateur Radio related project from a few years back that I previously had hosted on RedHat’s OpenShift. It was previously deployed on WildFly 8, so before I start making changes I want to get it deployed again locally on WildFly 8.

First up I got this error:

org.jboss.weld.exceptions.DeploymentException: WELD-001408: Unsatisfied dependencies for type ServiceLocator with qualifiers @Default at injection point [BackedAnnotatedField] @Inject private org.glassfish.jersey.internal.inject.ContextInjectionResolver.serviceLocator

This error appears to be pretty common. From the suggestions posted in reply to a similar post to WildFly forum here, the suggestion was to include Glassfish dependencies. I never had these included before, so not sure why I need these now, but these did the job:

<!-- kh added for error: WELD-001408: Unsatisfied dependencies for type Set<Service> with qualifiers @Default -->
<dependency>
  <groupId>com.google.guava</groupId>
  <artifactId>guava</artifactId>
  <version>17.0</version>
</dependency>

<!-- kh: added per: https://developer.jboss.org/thread/240847 -->
<dependency
  <groupId>org.glassfish.jersey.containers.glassfish</groupId>
  <artifactId>jersey-gf-cdi</artifactId>
  <version>2.14</version>
</dependency>

<dependency>
  <groupId>org.glassfish.jersey.containers</groupId>
  <artifactId>jersey-container-servlet</artifactId>
  <version>2.14</version>
</dependency>

The odd thing is if I deploy to WildFly 8.2 I don’t get this error or need these additional dependencies. Anyway, all set for now. I just tested deploying to 17.0.1 with no additional changes needed either.

Updating my AWS Lambda Sudoku Solver to generate new puzzles (part 1)

Having spent some time in the past building an implementation of Donald Knuth’s Algorithm X in Java to solve Sudoku Puzzles, I recently wondered what it would take to modify it to generate new puzzles.

If you missed my previous posts on this investigation, see:

It turns out having a working solver is part of the way there to implementing a puzzle generator, because you need to be able to check if a puzzle has a single solution, since valid puzzles only have 1 solution.

When I last wrapped my Solver as an AWS Lambda, I had taken the naive approach to call System.exit() in my Solver code if I detected there was more than 1 solution as a quick way to exit and not get stuck in a loop iterating over finding possible thousands of solutions for a grid that’s not a valid puzzle.

I went back and took another look at this and reworked it so I could pass an upper limit for number of puzzles, and changed the return type to return a List of solutions, and a flag indicating if there was a single solution or not. Latest commits on my repo have these changes, and I’m now ready to move on to building the puzzle generator. More updates coming soon.