Posts: 1
Joined: Wed Jun 12, 2019 4:25 pm

Autorefresh file upon save on multiple PIs

Wed Jun 12, 2019 4:31 pm

Hi all,

What I'm looking to accomplish is the following:

Hook up multiple Pis (Zero W or whatever is needed) to screens around an office and have them all display the same Excel file from a single location on the TVs that auto-refreshes when the file is either saved or can also be re-opened if the display on auto-save isn't a possibility.

I'd like to create something that can deploy headless once it's all up an running on one Pi.

I'm usually pretty good at mashing scripts I find together to accomplish what I need on the Pi, but this is a little above me.

Is this even possible? I'll dig harder if so. I tried searching the Goog for answers but am unsure of the syntax of the phrase to even search.

Thanks all!

Posts: 3078
Joined: Thu May 05, 2016 9:33 am
Location: Paris, France

Re: Autorefresh file upon save on multiple PIs

Wed Jun 12, 2019 6:20 pm

Well you can share a file via a networked file system, you can replicate a file (slower),
you can process the file so that it can be served by, e.g. a web server,
you can share the image of the screen from one machine.

Option 1 or 3 are probably the simplest.
If you need very high sync accuracy between screens, option 3 is the best, possibly with option 2 if the server/document format is smart and local updates can be sent instead of the whole file.
Display quality might take a hit with option 3. Multicasting would help with bandwidth control and client deployment.

I'm unsure option 2 is reasonable. Unless you move the file to Google Docs...
"S'il n'y a pas de solution, c'est qu'il n'y a pas de problème." Les Shadoks, J. Rouxel

Posts: 1237
Joined: Thu Apr 13, 2017 3:55 pm
Location: Oxford UK

Re: Autorefresh file upon save on multiple PIs

Wed Jun 12, 2019 6:27 pm

sounds like an ideal job for a light web server with a simple page that opens the document.

then have a script running to refresh the page every 5 mins or so on all the clients browsing the page to keep it upto date.

edit and save the master linked to by the web page and next time the regular refresh executes on the clients the doc should be up to date..

Posts: 3376
Joined: Sat Jun 16, 2018 12:49 am
Location: Lincs U.K.

Re: Autorefresh file upon save on multiple PIs

Wed Jun 12, 2019 6:30 pm

You may have a little problem if you are looking to refresh the sheet as per Microsoft shared sheets. ... eadsheets/ explains the sheet needs to be ODS format not xls.

I think you are going to have to pass updated copies of the sheet around to each Pi and open them.

What is the use case for sharing this? Would it be better to read the data from the sheet and display via a webpage?
Need Pi spray - these things are breeding in my house...

tpyo kingg
Posts: 555
Joined: Mon Apr 09, 2018 5:26 pm
Location: N. Finland

Re: Autorefresh file upon save on multiple PIs

Wed Jun 12, 2019 7:00 pm

Another way could be to have a script or unit file fetch the document from a web server using curl or wget and then display it with LibreOffice. See the --view option along with maybe also --display, --norestore, and --invisible. The web server could be one of the Raspberry Pis, but doesn't have to be.

Return to “Other projects”