scale-signs

digital signs for the Southern California Linux Expo

Server

• php5.4 with Apache httpd
• pulls an XML version of the conference speaking schedule down for the public socallinuxexpo.org web server
• sends formatted HTML to clients with the scale logo, wifi password, a scrolling schedule, sponsor logos, and relevant tweets

Client

• python script using the GTK library to simulate a full screen web browser which typically runs on raspberry pis

Views

Schedule

The main index page will display a carousel with a grid view of all currently running and upcoming sessions. The PI displays in the hallways typically display this view.

example: http://signs.scale.lan/

Room

The index page call be called with a room argument to display a room specific view that will display information relevant to that room.

Optimized for viewing at 1024x768 using one of the following room values:

• ballroom-a
• ballroom-b
• ballroom-c
• ballroom-de
• ballroom-f
• ballroom-g
• ballroom-h
• room-101
• room-103
• room-104
• room-105
• room-106
• room-107
• room-208
• room-209
• room-211
• room-212

examples:

• http://signs.scale.lan/?room=ballroom-de
• http://signs.scale.lan/?room=room-101

Development

It is sometimes necessary to test what the displays will look like at times other than the current. In order to do this the following variables must be modified in the uri:

• year
• month
• day
• hour
• minute

This is available in both Schedule and Room views

examples:

• http://signs.scale.lan/?year=2025&month=3&day=8&hour=9&minute=10
• http://signs.scale.lan/?room=ballroom-de&year=2025&month=3&day=8&hour=14&minute=33

NOTE: This will not work unless $starttime is correctly set for the current year of the show

Yearly Tasks

There is a bit of manual effort necessary from year to year. These tasks include, but might not be limited to:

• Do a search and replace for the previous scale version (example: replace all occurrences of 16x with 17x)
• verify proper XML is being supplied by drupal from the url reflected in the $url variable in room.php and scroll.php
• set $starttime in scroll.php which should reflect midnight of the first night of current year show. Example: if the show starts on 3/14/24, then the entry for startime should be: $starttime = mktime(0, 0, 0, 3, 14, 2024) / 60;.
• set $starttime in room.php to match scroll.php
• set $room_lookup_table in room.php to match all rooms being used for the current year
• set $room_lookup_table in index.php to match the one in room.php
• update $shorten_topics in scroll.php to reflect the updated track list, matching exactly the keys to what is being supplied by the xml from drupal minus spaces
• update $shorten_topics in room.php to match scroll.php
• create a style for each of the keys in $shorten_topics in style.css matching it to the public site
• add colors for topics/tracks in /server/style.css
• update the sponsor images in /server/images/sponsors/ to reflect the current year's sponsors, making them 220x220
• update $sponsors in room.php matching the value to each sponsor image file name
• update $sponsors_to_rooms in room.php matching proper sponsor(s) to room and day by key from $sponsors
• update the $logos and $logos2 arrays in sponsors.php attempting to distribute the list evenly across both case statements
• update the $diamond_platinum_sponsors array in room.php with the current year diamond and platinum sponsors
• update the $gold_sponsors array in room.php with the current year gold sponsors

Tips

Get rooms in use this year with:

export THIS_SCALE=22x; curl http://www.socallinuxexpo.org/scale/${THIS_SCALE}/sign.xml | grep "<Room>" | cut -d ">" -f 2 | cut -d "<" -f 1 | sort | uniq`

Get shortened topic list this year with:

export THIS_SCALE=22x; curl -q http://www.socallinuxexpo.org/scale/${THIS_SCALE}/sign.xml | grep "<Topic>" | cut -d ">" -f 2 | cut -d "<" -f 1 | sort | uniq | sed 's/ //g'`

Use ImageMagick to resize sponsor images

mogrify \
   -resize 200x200 \
   -background white \
   -gravity center \
   -extent 220x220 \
   *.png

Conference Operations

• git
• docker
• docker-compose

DST Issues

If DST changes during SCaLE, the next morning $starttime in scroll.php and room.php will need to be adjusted by an hour otherwise the schedule will be off. This should be as simple as following the instructions in the comments at the top of each file.

Build and start Service

1. git pull $this_repo
2. copy samples-secrets.env to secrets.env and populate with correct values
3. docker-compose up -d

Update from repo

1. git pull $this_repo
2. docker-compose build
3. docker-compose down
4. docker-compose up -d

You might need to force rebuilding without cache: docker-compose build --no-cache

Troubleshooting Basics

• docker-compose ps
• docker-compose logs [-f]
• docker-compose top

Local Testing:

• docker
• docker-compose

1. docker-compose build (repeat this every time code is changed to view results)
2. docker-compose up -d
3. browse to http://localhost:8088

Podman

If you prefer to use Podman, all docker and docker-compose invocations can be replaced with podman and podman-compose