I use Screenly OSE for displaying maps which are provided by the monitoring software PRTG. Basically, I paste the appropriate links to the web pages and Screenly calls them up.
However, since we updated PRTG, the maps are only displayed as a white page.
After some research, I am 90% sure that PRTG is now using a new version of Python (3), which Screenly cannot work with. However, Screenly is still running 2.7.16 and upgrading Screenly OSE doesn’t seem to help. I have also tried manually upgrading Python to 3.7 without success. After a reboot, the web interface shows a “504 Gateway Time-out” error and no output comes through HDMI.
Is there a newer version of the Screenly browser or is it maybe something different?
Hi APeters and everyone,
I also have this problem. Is there a fix?
Hello, just to give you both some quick info on this.
Screenly OSE using Python 2.7 or 3.x does not affect the experience you will have when it comes to rendering websites, this is a web browser engine + video driver handled situation.
The old Screenly OSE had a browser called UZBL, this was very old and obsolete/deprecated, didnt support modern websites, etc, and so OSE was upgraded to use QtWebView which uses new browser engine that needed to be compiled from scratch but just imagine that this is like a recipe of adding features one by one and the more you add the more resource heavy the application, and we are dealing with a Raspberry Pi, so think of using it as needing to be very light on resources in everything that is done with it while still supporting most modern websites. The Pi4 as far as I was reviewing code for is the only one that can build the necessary OpenGL drivers/libraries for the QtWebView browser to support this but it still doesnt show WebGL or OpenGL as active when i do a browser check.
If you try OpenStreetMap you will see that this website works because it allows for a different render to be used that QtWebView currently works with, but Google or Bing Maps dont work, I also experienced the white screen you refer to. If OpenStreetMap is capable of showing what you want to see and PRTG allows you to use it, that would be a good solution for this.
About the “504 gateway time-out” error, this simply means the Screenly web server is not up and running, not sure what happened exactly but I would suggest you start your OSE installation from scratch because reading about you trying to manually upgrade python 2.7 to 3 just gives me a little headache thinking of all that could have gotten messed up in terms of libraries etc.
To have a fresh install of the latest OSE, please do as follows:
Get a Raspbian Buster OS Lite image from here
After installation, do the normal initial setups with
sudo raspi-config like locale and stuff.
Then, run the OSE installation script:
bash <(curl -sL https://www.screenly.io/install-ose.sh)
This should only allow the installation of the latest version, it will take a while.
Once it is done, if you reboot and the screen stays black for a minute, press ctrl+alt+f1 and you will be in the Pi console again, once there, type
./screenly/bin/upgrade_containers.sh , this should commence the building of containers and putting them up, which will automatically bring up the OSE screen when finished.
The reason you need a fresh install is because I dont know how badly you messed up the python libraries and services and symbolic links in the Pi and once that happens it is very annoying to try and fix, when a fresh install is better anyway.